CORE PERFORMANcE
CORE PERFORMANcE GUIDE
GUIDE
Vermont Edition
Vermont Edition
Those who participate in Core Performance trainings or purchase the Core Performance Guide receive one year’s exclusive access to a continually updated library of reference materials. Materials include specific technical information, system specifications and information resources on the design process, envelope, lighting and daylighting, HVAC and power. To access this information, visit www.advancedbuildings.net/refmaterials.htm and type in your email and the following authorization code: abCPGvt1 (capitalization matters). Questions should be directed to Pat Heatherly at NBI,
[email protected].
COvER p HOTO: Thrivent Bank Building. Photo courtesy of Energy Center of Wisconsin.
Print version 1.02 Vermont Edition
Core Performance Guide
VERMONT EDITION
A prescriptive program to achieve significant, predictable energy savings in new commercial buildings
255 S. Champlain St., Suite 7 Burlington, VT 05401-4894 TOLL FREE (888) 921-5990 FAX (802) 658-1643 info@efficiencyvermont.com www.efficiencyvermont.com
Advanced Buildings and Core Performance are registered trademarks of New Buildings Institute • www.newbuildings.org
Publication Date: January 2008 ISBN # 0-9742969-2-9 Copyright © 2007 New Buildings Institute, Inc. All rights reserved, Advanced Buildings and Core Performance are registered trademarks of New Buildings Institute, Inc. Requests for permission or further information should be addressed to New Buildings Institute, Inc. at P.O. Box 2349, White Salmon, WA 98672 or via www.newbuildings.org Portions of this document © ASHRAE, www.ashrae.org. Reprinted by permission of American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., from ANSI/ASHRAE/IESNA Standard 90.1-2001. This material may not be copied nor distributed in either paper or digital form without ASHRAE’s permission. Portions of this document © Consortium for Energy Efficiency, www.cee1.org Consortium for Energy Efficiency (CEE) is a nonprofit corporation whose members are utility and other administrators and public stakeholders involved with energy efficiency programming. The CEE speci fications contained in this publication were developed by CEE members and other participants in its initiatives, are in the form in effect as of January 22, 2007, and are subject to change or withdrawal at any time by CEE. All such specifications are copyright protected and owned by CEE, and not New Buildings Institute. Information about the current status of any CEE specification may be obtained from CEE at its website, www.cee1.org, by clicking on the appropriate initiative.
WELCOME
Welcome to the Advanced Buildings’ Core Performance Guide Vermont Edition. Efficiency Vermont, Burlington Electric, Vermont Gas Systems, and other regional and national sponsors are offering the Core Performance Guide as an enhancement to the technical assistance and financial incentives currently offered through their commercial new construction programs. The Guide serves as an updated version of Benchmark, previously released and promoted by Efficiency Vermont. The new Core Performance Guide offers a simplified approach to achieve predictable energy savings in small-to-medium-sized commercial buildings—without the need for energy modeling. This document brings together over 30 criteria defining high performance in building envelope, lighting, HVAC, power systems, and controls. With this easy-to-use tool, building design and construction professionals will be able to establish clear targets and implement strategies to cost-effectively reduce energy use in new buildings by 20-30% compared to the Vermont Commercial Energy Code (2005 Vermont Guidelines for Energy Efficient Commercial Construction based on IECC 2004 and ASHRAE 90.1-2004). In general, the Core Performance requirements are most appropriate for new buildings and major renovations ranging from 10,000-70,000 square feet for offices, schools, and retail, but you can apply the concepts to projects of any size and building type. The program is divided into four categories: Design Process, Core Performance, Enhanced Performance Strategies, and Energy Modeling. Efficiency Vermont has established estimated energy savings and incentives available for the Core Performance package based on building type, HVAC system, and square footage, as well as for individual Enhanced Performance Strategies. This will allow designers to know the qualifying efficiency measures, the amount of energy these performance improvements are expected to save, and the financial incentives that can be expected if the 7 Design Process Strategies (Section 1) and 13 Core Performance Requirements (Section 2) are included in the building. Additional energy savings and incentives are possible for including the optional Enhanced Performance Strategies (Section 3) or following the optional Energy Modeling Method (Section 4). The Core Performance program has also been adopted by the US Green Building Council as a prescriptive alternative to energy modeling to achieve up to five LEED points in the Optimize Energy Performance credit (EA credit 1). All LEED buildings are now required to achieve at least two points in this credit in order to qualify for LEED certification. Improving the energy efficiency of new buildings is critical to helping Vermont meet its current and future energy needs, as well as reducing the environmental impact of our built environment. The most cost-effective time in the lifespan of a building to improve its’ efficiency is during design and construction rather than retrofitting it once it’s built. Core Performance is a straightforward and predictable process to achieve significant efficiency and performance improvements. For projects located in Burlington, please contact Burlington Electric at 802-865-7337. For all other locations, please contact Efficiency Vermont at 888-921-5990 to enroll your next project and get started!
ACKNOWLEDGEMENTS
ABOUT NE W BUILDINGS INS TITUTE New Buildings Institute (NBI) is a nonprofit corporation helping make buildings better for people and the environment. NBI supports policies, accelerates the adoption of new technologies and practices, and enables field research that improves the energy performance of new commercial buildings. NBI works with national, regional and state organizations, as well as with utilities and design professionals, to advance our mission. We closely coordinate our building research, design guidelines and other tools, as well as policy efforts so that all of the elements of good building design are integrated into the products and services we make available for use by energy efficiency programs and building professionals throughout the country. NBI IS SUPP O R TED BY : California Energy Commission Efficiency Vermont Energy Foundation Iowa Energy Center National Grid, USA New York State Energy Research and Development Authority Northeast Energy Efficiency Partnerships Northwest Energy Efficiency Alliance NSTAR Sacramento Municipal Utility District Southern California Edison U.S. Environmental Protection Agency
Special thanks to the U.S. Environmental Protection Agency for their support and funding contribution for the development of this guide. ADVANCED BUILDINGS CORE PERFORMANCE PROJEC T TE A M
AUTH O R :
Jeff Cole, Konstruct, Inc. Scott Criswell, SAC Software Solutions Inc. Dave Hewitt, New Buildings Institute Kevin Madison, Madison Engineering P.S. Howdy Reichmuth, New Buildings Institute Cathy Turner, New Buildings Institute
Mark Frankel, Technical Director, New Buildings Institute
TECHNIC AL CO NTRIBUTOR S :
Mark Cherniack, New Buildings Institute Terry Egnor, MicroGrid ACKNOWLED GEMENT OF CONTRIBUTOR S
We gratefully acknowledge the following individuals for their contributions and insights in the development of the Advanced Buildings Core Performance Guide. Marge Anderson, Energy Center of Wisconsin Fran Boucher, National Grid, USA Karen Butler, Environmental Protection Agency Charlie Grist, Northwest Power and Conservation Council Jon Heller, Ecotope Brendan Owens, U.S. Green Building Council Mike Rosenberg, Oregon Department of Energy Marcus Sheffer, 7group Brian Thorton, Thornton Energy Consulting Mira Vowles, Bonneville Power Administration
ACKNOWLED GMENT OF RE VIE WER S We’d like to thank the following individuals who contributed time and energy to review this publication. Their feedback has ensured the usefulness and usability of the Core Performance Guide. Douglas Baston, North Atlantic Energy Roseann Brusco, NSTAR John Burns, Cape Light Compact Lee DeBaillie, Energy Center of Wisconsin Martine Dion, Symmes Maini & McKee Associates Kim Dragoo, KeySpan Energy Mark Eggers, New York State Energy Research and Development Authority David B. Goldstein, Natural Resources Defense Council Frank Gundal, NSTAR Jeff Harris, Northwest Energy Efficiency Alliance John Hogan, City of Seattle DE VELOPMENT PROCESS FOR ADVANCED BUILDINGS CORE PERFORMANCE The Criteria and information provided in Advanced Buildings Core Performance is based on NBI’s previous Advanced Buildings protocol, Benchmark. New Buildings Institute developed Benchmark following a set of requirements largely based on the ANSI Procedures for the Development and Coordination of American National Standards©. In accordance with those requirements, a national Criteria Review Committee consisting of a balance of code officials, utility new construction program staff, and interested and affected parties representing the design, construction, real estate and manufacturing communities reviewed, voted on and approved the Benchmark. As the next version of Benchmark, Core Performance has retained much of the original publication’s content in terms of process and priorities. However, based on our experience with how people use Benchmark, information in the Core Performance Guide has been reorganized and updated to facilitate ease of use. We want to acknowledge Benchmark’s author, Jeff Johnson, former executive director of NBI. His dedication to the cause of high performance building made development of Benchmark and the Advanced Buildings program possible. In addition, special thanks goes to the Energy Center of Wisconsin for their partnership in these efforts. Finally, we’d like to thank the members of the Benchmark Criteria Review Committee for the countless hours they contributed to this process. John Jennings, Northwest Energy Efficiency Alliance Jonathan Kleinman, Optimal Energy, Inc. Michael McAteer, National Grid, USA Nelson Medeiros, NSTAR Charles Michal, Weller & Michal Architects, Inc. Curt Nichols, Idaho Power Jay Pilliod, Vermont Energy Investment Corporation Gena Tsakiris, NSTAR Abby Vogen Horn, Energy Center of Wisconsin Tate Walker, Energy Center of Wisconsin Nancy Yap, BC Hydro
AUTHORIZ ATION New Buildings Institute, Inc. (“NBI”) authorizes you to view the following Advanced Buildings Core Performance Guide Vermont Edition, January 2008 (“Core Performance Guide” ) for your individual use only. The reproduction or distribution of the whole, or any part, of the contents of the Core Performance Guide without express written permission of NBI is prohibited. DIS CL AIMER OF WARR ANTIES The following parties have participated in funding, creating and/or preparing the Core Performance Guide: NBI, the Energy Foundation, California Energy Commission, Cape Light Compact, Efficiency Vermont, National Grid USA, New York State Energy Research and Development Authority, Northwest Energy Efficiency Alliance, NSTAR, Sacramento Municipal Utility District, Southern California Edison, and U.S. Environmental Protection Agency (collectively referred to herein as “the Parties”). The Core Performance Guide is provided “as is” and is for informational purposes only. No building application should be undertaken without first consulting a licensed contractor, or other building professional. The Parties do not warrant the accuracy, adequacy, or completeness of the Core Performance Guide, and expressly disclaim liability for errors or omissions in the information. NO WARRANTY OF ANY KIND, IMPLIED, EXPRESS, OR STATUTORY, IN EXISTENCE NOW OR IN THE FUTURE, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF NON-INFRINGEMENT OF THIRD PARTY RIGHTS, TITLE, MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE IS GIVEN BY THE PARTIES. THE PARTIES UNDERTAKE NO RESPONSIBILITY FOR THE QUALITY OF THE CORE PERFORMANCE GUIDE. THE PARTIES ASSUME NO RESPONSIBILITY THAT THE CORE PERFORMANCE REPORT WILL BE FIT FOR ANY PARTICULAR PURPOSE FOR WHICH YOU MAY BE ACQUIRING THE CORE PERFORMANCE GUIDE. LIMITATION OF LIABILIT Y The Parties do not assume responsibility for any damages or other liability whatsoever (including any consequential damages) as a result of any use of the Core Performance Guide. As a condition of your use of the Core Performance Guide, you covenant not to sue, and agree to release the Parties from liability, and waive any and all claims, demands and causes of action against the Parties.
Table of Contents
Introduction
Core Performance Program Quick Start Guide Integration of Core Performance with USGBC LEED Program 11 17 25
Section One: Design Process Strategies
1.1 1.2 1.3 1.4 1.5 1.6 1.7 Identify Design Intent Communicating Design Intent Building Configuration Mechanical System Design Construction Certification (Acceptance Testing) Operator Training and Documentation Performance Data Review 31 33 36 37 39 41 42
Section Two: Core Performance Requirements
2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 Energy Code Compliance Air Barrier Performance Minimum IAQ Performance Below-Grade Exterior Insulation Opaque Envelope Performance Fenestration Performance Lighting Controls Lighting Power Density Mechanical Equipment Efficiency Requirements Dedicated Mechanical Systems Demand Control Ventilation Domestic Hot Water System Efficiency Fundamental Economizer Performance 45 46 48 49 50 53 55 58 62 67 68 70 71
Table of Contents
Section Three: Enhanced Performance Strategies
3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 Cool Roofs Daylighting and Controls Additional Lighting Power Reductions Plug Loads/Appliance Efficiency Supply Air Temperature Reset (VAV) Indirect Evaporative Cooling Energy Recovery Night Venting Premium Economizer Performance Variable Speed Control Demand-Responsive Buildings (Peak Power Reduction) On-Site Supply of Renewable Energy Additional Commissioning Strategies Fault Detection and Diagnostics 75 76 77 78 80 81 84 85 86 88 89 90 91 93
Section Four: Energy Modeling
4.1 Determine Performance with Energy Modeling 99
Appendices
Appendix A: Acceptance Requirements for High Performance Buildings Appendix B: Climate Zone Map Appendix C: Acronyms and Definitions 103 121 122
Introduction
Introduction
Core Performance Program Quick Start Guide Integration of Core Performance with USGBC LEED Program
This section provides an explanation of the Core Performance program and how it was developed. Included in this section is the Quick Start Guide which provides an overview of the program.
Core Performance Program
INTRODUC TION TO ADVANCED BUILDINGS CORE PERFORMANCE Advanced Buildings Core Performance is a prescriptive program to achieve significant, predictable energy savings in new commercial construction. The program describes a set of simple, discrete integrated design strategies and building features. When applied as a package, they result in energy savings of at least 20 to 30% (depending on climate) beyond the performance of a building that meets the prescriptive requirements of ASHRAE 90.1-2004, or in Vermont, the 2005 Vermont Guidelines for Energy Efficient Commercial Construction (Vermont Commercial Energy Code), and at least 25 to 35% beyond a building that meets ASHRAE 90.1-2001. This program is the revised and updated version of the Advanced Buildings Benchmark program released previously. Elements of the program can be applied to new commercial construction projects of all sizes, but the Criteria and analysis supporting the program were designed particularly for smaller scale commercial projects ranging from 10,000 to 70,000 square feet. At the larger end of this range, HVAC system complexity may suggest additional energy savings opportunities not fully addressed by a prescriptive program. However, even much larger projects with simple mechanical systems can benefit from the Core Performance savings strategies. Building envelope and lighting system energy savings strategies in Core Performance are scalable to projects of any size. The program is based on the results of an extensive energy modeling protocol used to identify consistent strategies that lead to anticipated energy savings across climates. These strategies are combined in a prescriptive guideline for new construction to guide energy performance improvements. The analysis included evaluations of three major building prototypes, four HVAC system permutations for each prototype, evaluated for climate variations for 16 U.S. cities. The program also includes guidelines on implementing improved design processes to foster design integration, thereby improving overall building performance opportunities. These strategies set the stage for additional whole building performance improvements beyond the basic requirements of this program. A key aspect of the Core Performance program is that the strategies that make up the program represent ‘state of the shelf’ technologies and practices that are broadly available in the building industry, and have been demonstrated to be cost-effective. The basic component of the program is the Core Performance Guide (this document), which identifies the specific strategies that make up the Core Performance program. Design teams can use the Guide to identify and implement all of the strategies (referred to as Criteria) that must be implemented to comply with program requirements. The Guide also identifies additional strategies that can be used to go beyond the basic performance goals of the Core Performance program. To support the Core Performance program, an extensive set of reference materials provides additional information on implementation, design practice, research, additional strategies and advanced practices for more effectively using the Core Performance Guide. This information is available for review and download by program participants at www.advancedbuildings.net. The Core Performance program is also supported by an extensive training curriculum delivered periodically by Advanced Buildings (AB) program partners in various regions around the country. Training schedule and registration details are also available at the Advanced Buildings website. The Advanced Buildings program is also being offered through a growing number of utilities that are offering technical and financial support for Advanced Building project owners, designers, and builders. A current list of Advanced Buildings program sponsors/subscribers is also available on the website.
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
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S TRUC TURE O F ADVANCED BUILDINGS CORE PERFORMANCE GUIDE The performance Criteria are broken into four categories: Design Process Strategies, Core Performance Requirements, Enhanced Performance Strategies, and Energy Modeling.
D E SIG N PRO CE SS S TR ATEG IE S
The Design Process Strategies are developed to make the design process more effective, leading to more integrated design outcomes. This category defines specific steps which are required to comply with program requirements. These requirements include defining design intent with respect to energy performance, part-load evaluation of mechanical loads, acceptance testing, and long-term performance monitoring. All Design Process Strategies must be met to fully comply with the Core Performance program. Research indicates that these design strategies will lead to better building performance, but the energy impacts on a given building are difficult to quantify. These outcomes are not quantified or included when estimates of “savings compared to ASHRAE 90.1” are discussed.
Integrated design is an iterative process whereby decisions made at each stage must be considered in the context of impacts on all design elements.
CO R E PER FO R MANCE REQUIREMENT S
The second category is the heart of the Core Performance program. This category includes specific building performance requirements that exceed energy code requirement, lead to measurable energy savings, and support the persistence of those savings in each building type. The efficiency measures in this category are included because they lead to consistent, predictable energy savings across project type and climate. All of the Core Performance requirements in this section must be met to comply with the AB program.
ENHANCED PERFOR M ANCE S TR ATEGIE S
The third category in Core Performance is Enhanced Performance. This category includes measures that may be appropriate only for certain system or building types, or certain climates, as well as performance strategies that are relatively new to the market. There are significant energy savings opportunities represented by these strategies, but their application must be considered on a case-by-case basis. These measures are targeted for projects aiming
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INTRODUCTION ○ CORE PERFORMANCE PROGRAM
to exceed the basic requirements of the AB program such as those aiming for federal tax incentives for a 50% reduction in energy cost, and for projects that require a more customized approach to the measure list. The Enhanced Performance section also includes strategies such as load shedding for demand-restricted utility billing structures, alternative energy systems, and advanced commissioning strategies.
ENERG Y MODELING
The fourth section of Core Performance is the Energy Modeling section. Energy modeling can be used to target more aggressive energy performance and to help identify which Enhanced Performance Strategies might be most effective for any given project. Energy modeling may also be used by some projects to demonstrate equivalent performance to the prescriptive standard with greater flexibility. Projects that cannot meet certain required Core Performance Criteria may choose to use energy modeling to demonstrate that alternate strategies achieve the same level of energy performance. Energy modeling can also be used to customize the Core Performance list, adding strategies from the Enhanced Performance section to replace specific elements of the Core Performance section based on specific project conditions. Because an extensive energy modeling protocol was used to develop the Core Performance program, the specific Criteria included in the program represent an excellent starting point for any project undertaking energy modeling. Using the Core Performance Criteria as a baseline in an energy modeling exercise may substantially simplify the complexity of energy modeling that may be undertaken for a specific project.
FOR A QUICK OVERVIEW OF THE REQUIREMENTS AND ELEMENTS OF THE CORE PERFORMANCE PROGR AM, CONSULT THE QUICK START GUIDE AT THE END OF THE INTRODUC TION SEC TION OF THIS GUIDE .
CORE PERFORMANCE AND LEED There are a number of parallel strategies between Advanced Buildings Core Performance and the United States Green Building Council’s ( USGBC) LEED program. Specific Criteria within Core Performance are directly aligned with specific LEED credits and represent strategies that partially or completely achieve specific LEED credits. Within this Core Performance Guide, the relationship of specific Criteria to the requirements of LEED NC 2.2 is identified in the margin at the end of each Criteria. This information indicates specific LEED credits that overlap or parallel the performance Criteria. Actions taken to meet Core Performance requirements will contribute directly to achievement of LEED credits. Users should review the LEED reference guide to identify specific requirements and credit achievement opportunities. The Core Performance program also represents a comprehensive approach to the energy performance aspects of the LEED program. The USGBC is currently considering a direct correlation between use of Core Performance and a specific point score under Energy and Atmosphere Credit 1 (EAc1); Energy Performance. These points would be achieved prescriptively, without energy modeling. Note however that each project must follow the guidelines of the USGBC to achieve LEED points.
INTRODUCTION ○ CORE PERFORMANCE PROGRAM
13
ANALYSIS SUPP OR TING CORE PERFORMANCE An extensive energy modeling protocol has been implemented to support the development of the Advanced Buildings Core Performance program. The results of over 30,000 energy modeling runs using eQUEST software to run DOE-2 have been evaluated using a batch analysis protocol built into the eQUEST energy modeling tool. For each of the prototype buildings, three to five typical mechanical systems were defined to represent typical construction practice. Sixteen representative U.S. cities were identified to serve as “typical” climate representatives of the eight ASHRAE climate zones and the various permutations identified within those climate zones by ASHRAE. A baseline building that meets the requirements of ASHRAE 90.1-2004, or in Vermont, the Vermont Commercial Energy Code, was defined for each permutation of the above Criteria (building type, system type, climate). Note that the baseline building is defined using the prescriptive requirements of ASHRAE 90.1 (2001 and 2004). In Vermont, the baseline building is defined using the prescriptive requirements of the Vermont Commercial Energy Code. As a prescriptive standard, Core Performance will be applied to buildings that would typically not complete energy modeling, and therefore the prescriptive requirements more accurately represent the target market for this program. Modifications to the batch protocol software in eQUEST were developed to provide an ordered ranking of the energy efficiency measures modeled for this project. There are approximately 14-16 discrete energy performance measures (depending on system configuration) within the analysis that can be applied to each baseline. The batch protocol ran each of these measures individually against the appropriate baseline and identified the one with the most significant energy savings impact. This measure was then added to the baseline, and the remaining measures were run individually against this revised baseline. This process continued until all of the measures were ranked by energy savings impact, and the final run represented the sum total energy savings of all of the measures if considered as a package. The results of this analysis were then compared across prototype, system and climate to determine which measures were the most consistently significant across these variants. The most consistent measures became the basis for the Core Performance package of Criteria requirements. Other measures which were applicable to a subset of the variants or which had climate- and system-specific advantages were included in the Enhanced Performance section. The importance of identifying the most significant strategies from an energy savings standpoint can be seen in Figure 1. As successive energy savings strategies are added to the baseline, the impact on energy performance becomes less significant. Failure to consider measure impacts as a package may lead to over-estimation of the energy savings associated with each measure.
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INTRODUCTION ○ CORE PERFORMANCE PROGRAM
Figure 1 below shows the anticipated average energy savings over the prescriptive requirements of ASHRAE 90.1-2004, or in Vermont, the Vermont Commercial Energy Code, as the modeled measures in Core Performance are incorporated into the analysis sequentially. Each line in this graph represents one of the representative cities modeled using the Core Performance Criteria (Note that some of the Criteria included in the program do not directly address modeled energy use, and are not represented on this graph.). More information about the analysis protocol and results can be found at www.advancedbuildings.net.
40% 35% 30% Fairbanks Phoenix San Francisco Miami Boise Chicago Baltimore Duluth Helena Alburquerque Memphis El Paso Houston Burlington Seattle
Percent Savings
25% 20% 15% 10% 5% 0%
Cumulative Energy Efficiency Measures
FIGURE 1 - CUMUL ATIVE EFFEC T OF ENERG Y EFFICIENC Y ME A SURE S APPLIC ABILIT Y OF CORE PERFORMANCE In general, the Core Performance program requirements are best suited to buildings ranging from less than 10,000 to 70,000 square feet. For larger projects, the program represents a good set of guidance on design strategies and performance measures.
BUILD ING SIZ E
Small to mid size buildings are the focus of Core Performance, but the energy savings strategies that are part of the program are valid at a larger scale. The design strategies, envelope, lighting, and most system measures in Core Performance are applicable to buildings of any size. However, larger building types are more likely to adopt more complicated systems and energy conservation strategies that are not as predictably described in a prescriptive standard. Larger buildings have opportunities for more robust systems and controls and are also more likely to benefit from full-scale energy modeling. For larger projects, the design team should evaluate the complexity of the HVAC systems to determine if the project would be better served by an effective energy modeling strategy, as described in Section Four: Energy Modeling.
BUILD ING T Y PE
The Core Performance program was developed on the basis of prototype analysis of several major project categories. The prototype buildings used in the analysis represent approximately two-
INTRODUCTION ○ CORE PERFORMANCE PROGRAM
15
thirds of commercial buildings, according to the Commercial Building Energy Consumption Survey (CBECS). In addition, a number of other project types have strong similarities to these project types in the context of the energy performance measures in Core Performance. The table below identifies the project type designations used by CBECS and shows the applicability of the Core Performance program to these project types. For those projects identified as partially compatible with Core Performance, it may be necessary to identify a specific subset of the Core Performance Criteria that is appropriate in the context of the project. All projects may have special conditions requiring the project team to use professional judgment on the application of specific Core Performance Criteria. TABLE 1 - APPLIC ABILIT Y OF CORE PERFORMANCE BY PROJEC T T Y PE
APPLIC ABILIT Y OF CO R E P E R F O R M A N C E BY P ROJECT T YP E
BUILD ING T Y PE O FFIC E EDUC ATION PUBLIC A SSEMBLY RE TAIL PUBLIC O RD ER PERC ENT O F NATIONAL M ARK E T
17% 8% 13% 26% 1%
COMPATIBILIT Y WITH CO R E PER FO R MAN CE
NOTES
All major building elements addressed. All major building elements addressed. All major building elements addressed. All major building elements addressed; some retail types may have special loads. All major building elements addressed; some projects may have special loads. Core Performance addresses many aspects of these projects, but special needs and systems for health care must be evaluated on a case by case basis. Aspects of Core Performance may not be appropriate for hospital and outpatient specialty clinics. All major building elements addressed; some project types may have special loads or conditioning requirements. Kitchen and food preparation loads not addressed by Core Performance. Only some elements of Core Performance are directly applicable to lodging. Evaluate applicability on a case-by-case basis.
HE ALTH
3%
WAREH O USE FO O D LO D G ING OTHER
12% 11% 3% 6%
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INTRODUCTION ○ CORE PERFORMANCE PROGRAM
Quick Start Guide to the Core Performance Program
The Core Performance program is built around process and performance requirements that are identified in the specific Criteria that make up the program. These Criteria are divided into three categories: Design Process Strategies, which describe coordination, implementation, and verification requirements of the program. Core Performance Requirements, which include the basic performance requirements for specific building elements. Enhanced Performance Strategies, which include a number of additional performance measures which may be appropriate for specific projects targeting additional energy savings. A fourth category, Energy Modeling, is included for projects pursuing a more robust analysis of project-specific performance opportunities. Energy modeling can be used to target more aggressive energy performance or to help prioritize strategies in the Enhanced Performance section that may be particularly effective for a specific project. The requirements of each Criteria are explained in the Core Performance Guide. As an overview, a brief description of each Criteria is provided below. The specific requirements of each Criteria within the Core Performance Guide should be consulted to determine the specific and complete requirements of each Criteria. Additional reference material on application and implementation strategies can be found at www.advancedbuildings.net.
1- D E SIG N PRO CE SS S TR ATEG IE S
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
The Criteria in this section describe required steps for the design team to effectively implement the Core Performance program. These strategies provide a framework for successful design integration and protocols to verify the intent, implementation and outcome of the design process. 1.1 IDENTIF Y DE SIGN INTENT Conduct a team meeting to identify key energy goals for the project and to coordinate subsequent efforts among team members. Document the meeting summary/goals statement for use in subsequent steps, and use ENERGY STAR Target Finder to set specific performance goals for the project. 1.2 COMMUNIC AT ING DE SIGN INTENT Develop key information about project performance requirements to insure that design goals are translated forward through the design process. Project goals are converted into documentation incorporated into each phase to guide design, sequence of operation, specifications, bid submittals, construction, acceptance testing and building operation. 1.3 BUILDING CO NFIGUR ATION Consider the implications of alternate building configurations to maximize building energy performance, functionality and daylighting. Identify the pros and cons of several alternate building configurations using existing analysis tools, consultants, reference material or other resources.
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1.4 MECHANIC AL SYS T E M DE SIGN Use project-specific load calculations based on Core Performance requirements and part load conditions to properly size mechanical equipment, rather than relying on generic rule-of-thumb sizing Criteria. 1. 5 CO NS TRUC TION CERT IFIC AT ION (ACCEPTANCE TE STING ) Implement an Acceptance Testing protocol to test the operational characteristics of installed systems. Document that installed systems are operating as intended prior to occupancy. It is up to the project team to identify the key systems to be tested and verified to insure that the project meets the performance goals identified by the owner and design team. Specific guidance on test protocols are provided in Appendix A. Projects intending to seek a LEED rating should note that additional steps and conditions beyond this Criteria are necessary to meet the LEED commissioning prerequisite. Also see Criteria 3.13, Additional Commissioning Strategies, to better align with LEED requirements. 1.6 OPER ATOR TR AINING AND DOCUMENTAT ION Collect a full set of construction documents and specifications, systems manuals, maintenance and calibration requirements, control protocols, etc. for use by the building operations team. Conduct an operator training session to make sure the building operators understand the systems and operation of the building. Information should be collected in a set of manuals designed to facilitate building operation and future communication of this information to new operating staff. Work with the building owner to identify the best way to collect, store and distribute this information. 1.7 PERF OR MANCE DATA RE VIE W Install digital utility meters capable of collecting hourly utility use data. Implement a data collection protocol on-site, with the local utility or a third party to collect this data. A summary of the information should be reviewed quarterly by building operations staff and included in the maintenance manual to track long-term building performance trends and identify potential system performance issues. Some building managers may choose to review this data more frequently to support ongoing operational improvements and maintenance.
2- CO R E PER FO R MANCE REQUIREMENT S
All of the Criteria listed in this section are required components of the Core Performance program. Energy savings projections are based on the implementation of all applicable measures in this section. 2.1 ENERGY CODE COMPLIANCE In addition to implementing the requirements of the Core Performance program, projects using the program must meet all local energy code requirements or the prescriptive requirements of ASHRAE 90.1-2004, whichever is more stringent. In Vermont, projects must meet the Vermont Commercial Energy Code.
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INTRODUCTION ○ QUICK START GUIDE
2.2 AIR BARRIER PERF OR MANCE During design and construction, develop and implement air sealing details and protocols to reduce uncontrolled air movement through the building envelope and duct systems. 2. 3 MINIMUM IAQ PERF O R M ANCE Implement protocols to insure acceptable indoor air quality, including meeting or exceeding ASHRAE Standard 62-2004, developing and implementing air quality management plans for construction and operation, and conducting a building flush-out prior to occupancy. 2.4 BELOW- GR ADE E X TERIOR INSUL ATION Apply exterior below-grade insulation in humid climates to reduce moisture transport into the building. 2. 5 OPAQUE ENVELO PE PERF OR MANCE Meet specific insulation Criteria for each building envelope assembly. 2.6 FENE S TR ATION PERF OR MANCE Meet specific window performance Criteria for u-value and solar heat gain coefficient, based on NFRC ratings. Performance requirements are based on entire window assembly, not glazing alone. 2.7 LIGHTING CONTROL S Install control systems throughout the building, including occupancy sensors and time clock controls. Daylit areas are encouraged to incorporate daylight controls, but at a minimum these areas must be provided with separate switching to facilitate future incorporation of daylight control systems. 2.8 LIGH TING POWER DENSIT Y Projects may not exceed the lighting power density limits indicated in this Criteria. 2.9 MECHANIC AL EQUIPMENT EFFICIENC Y REQUIRE MENTS Mechanical equipment must meet the performance Criteria developed by the Consortium for Energy Efficiency (CEE) labeled as Tier 2 performance requirements. 2.10 DEDIC AT ED MECHANIC AL SYS T E MS Spaces in the building with specific process loads or that require conditioning significantly different from the main building spaces must be provided with a separate, dedicated mechanical system designed specifically for these loads. 2.11 DEMAND CO NTROL VENTIL AT ION Outside airflow should be controlled by a system which measures CO2 and provides airflow based on occupant density, as measured by the CO2 sensor.
INTRODUCTION ○ QUICK START GUIDE
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2.12 HOT WATER SYSTE M EFFICIENC Y Domestic hot water demand should be met by either demand hot water heaters or highefficiency condensing appliances. 2.13 FUNDAMENTAL ECONOMIZER PERF OR MANCE This Criteria includes a list of features and performance verification strategies to insure proper and effective economizer operation.
3- ENHANCED PERFOR M ANCE S TR ATEGIE S
The Criteria in this section are not part of the basic requirements of the Core Performance program. The strategies identified here represent opportunities for significant additional energy savings beyond basic program requirements. Individual Criteria in this section should be considered in the context of project characteristics and climate conditions. 3.1 CO O L R O O FS Install an ENERGY STAR-labeled cool roof on the project. 3.2 DAYLIGHTING AND CO NTROL S Incorporate daylighting and control systems to take advantage of natural light to reduce electric lighting loads. 3.3 ADDITIONAL LIGHTING POWER REDUC T IONS Reduce connected lighting loads to achieve the lighting targets of the Energy Policy Act of 2005. These lighting levels are roughly 40% below ASHRAE 90.1-2001. Note that implementing this Criteria can qualify the project for federal tax deductions of $0.30 to $0.60 per square foot of building floor area. For public projects, this tax deduction can be passed through to the design team. 3.4 PLUG LOADS/APPLIANCE EFFICIENC Y Use ENERGY STAR-rated equipment for all appliances, computers and other equipment. Commit to a long-term acquisition plan that targets efficiency in equipment replacement and upgrades. Implement power management strategies for equipment. 3. 5 SUPPLY AIR TEMPER ATURE RE SE T ( VAV ) VAV systems should include control capabilities to reset supply air temperature to the warmest setting that will meet cooling load in all zones. 3.6 INDIREC T E VAP OR AT IVE CO OLING Use indirect evaporative cooling systems to reduce cooling load served by conventional cooling systems.
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INTRODUCTION ○ QUICK START GUIDE
3.7 ENERGY RECOVERY Incorporate a heat recovery system in the ventilation air exhaust stream for spaces with high occupancy or high outdoor air ventilation requirements. 3.8 NIGHT VENTING Install a control system capable of implementing a night venting protocol to use outside air to pre-cool interior building mass during cool night hours. This strategy reduces peak and daily cooling energy use in the cooling season. 3.9 PREMIUM ECONOMIZER PERF OR MANCE Include additional control and verification features into the building economizer system. 3.10 VARIABLE SPEED CO NTROL Provide variable flow capabilities for air and fluid systems served by pumps and fans with motor horsepower of 5hp or larger. 3.11 DEMAND - RE SPONSIVE BUILDINGS ( PE AK POWER REDUC TION ) Implement systems and control strategies that allow buildings to reduce electrical energy use during peak power demand periods, as identified by the local utility. 3.12 ON -SITE SUPPLY OF RENE WABLE ENERGY Install on-site renewable energy systems to supply 10% or more of building electric or thermal loads. 3.13 ADDITIONAL COMMISSIONING STR ATEGIE S Engage a third-party commissioning agent to participate in design reviews during the design process. Consider using the third-party commissioning agent as the primary commissioning agent for the project as a whole. This strategy would align more directly with the commissioning requirements of LEED. 3.14 FAULT DE TEC TION AND DIAGNOSTIC S Include integrated monitoring systems in manufactured rooftop HVAC equipment to help ensure optimal system performance.
4 - ENERG Y MO D ELING
Energy modeling can be used as an alternate path to achieve or exceed the goals of the Core Performance program. Strategies identified in previous sections should be implemented to the extent possible, and energy modeling should be used to identify additional savings opportunities. 4.1 PREDIC T PERF OR MANCE WITH ENERGY MODELING Use an hourly energy model simulation tool to incorporate building features that exceed the requirements of ASHRAE 90.1 (in Vermont, the Vermont Commercial Energy Code) by 20% or more. Energy modeling can also be used to help determine which of the enhanced performance strategies are most promising for a speci fic project.
INTRODUCTION ○ QUICK START GUIDE
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KE Y DESIGN PHA SES FOR IMPLEMENTATION OF CORE PERFORMANCE PROGR A M CRITERIA
S C H E M AT I C DESIGN DESIGN D E V E LO P M E N T CONS TR UC TI ON DOCUMENTS CONS TR UC TI ON COMPLETI ON
R E Q U I R E D S T R AT E G I E S ( S E C T I O N S 1 A N D 2 ) 1.1 1.3 1.2 1.4 2.1 2.5 2.6 2.8 2.9 2.10 2.11 2.4 2.7 2.12 1.5 2.2 2.3 2.13 1.6 1.7 3.13 3.6 3.7 3.8 3.2 3.3 3.11 3.12 3.10 3.1 3.9 3.5 3.4 IDENTIFY DESIGN INTENT B UILDING CONFIGUR ATION COMMUNIC ATING DESIGN INTENT MECHANIC AL SYSTEM DESIGN ENERGY CODE COMPLIANCE OPAQUE ENVELOPE PERFORMANCE F E N E S T R AT I O N P E R F O R M A N C E LIGHTING POWER DENSIT Y MECHANICAL EQUIPMENT EFFICIENCY DEDIC ATED MECHANIC AL SYSTEMS D E M A N D CON T R O L V E N T I L AT I O N BE LOW - G R A D E E X T E R I O R I N S U L AT I O N LIGHTING CONTROLS HOT WATER SYSTEM EFFICIENCY CO N S T R U C T I O N C E RT I F I C AT I O N AIR BARRIER PERFORMANCE MINIMUM IAQ PERFORMANCE F U N D A M E N TA L E CO N O M I Z E R P E R F O R M A N C E O P E R ATO R T R A I N I N G PERFORMANCE DATA RE VIE W A D D I T I O N A L CO M M I S S I O N I N G INDIRECT E VAPOR ATIVE COOLING ENERGY RECOVERY NIGHT VENTING DAYLIGHTING AND CONTROLS ADDITIONAL LIGHTING POWER REDUCTIONS DEMAND RESPONSIVE BUILDINGS RENE WABLE ENERGY VARIABLE SPEED CONTROL COOL ROOFS PREMIUM ECONOMIZER PERFORMANCE SUPPLY AIR TEMPER ATURE RESET PLUG LOADS/APPLIANCE EFFICIENCY STR ATEGY ADDRESSED IN THIS PHASE KE Y IMPLEMENTATION PHASE OF STR ATEGY
E N H A N C E D P E R F O R M A N C E S T R AT E G I E S
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INTRODUCTION ○ QUICK START GUIDE
O P E R AT I O N
PREDESIGN
BIDDING
ROLE OF PROJEC T TE AM MEMBER S IN IMPLEMENTATION OF CORE PERFORMANCE PRO GR A M CRITERIA
ME C HA NI C A L ENGINEER LI G HTI NG DESIGNER CON T R ACTOR OCCUPANTS
ARCHITECT
OWNER 1.1 1.2 1.6 1.7 3.4 1.1 1.2 1.3 2.1 2.2 2.4 2.5 2.6 3.1 3.2 3.8 3.12 1.1 1.2 1.4 2.1 2.10 2.11 2.12 2.3 2.9 3.5 3.10 3.6 3.7 3.8 3.11 3.12 IDENTIFY DESIGN INTENT COMMUNIC ATING DESIGN INTENT OP E R ATOR T R A I N I N G PERFORMANCE DATA RE VIE W PLUG LOADS/APPLIANCE EFFICIENCY IDENTIFY DESIGN INTENT COMMUNIC ATING DESIGN INTENT B UILDING CONFIGUR ATION ENERGY CODE COMPLIANCE AIR BARRIER PERFORMANCE BE LOW- G R A D E E X T E R I O R I N S U L AT I O N OPAQUE ENVELOPE PERFORMANCE FENESTR ATION PERFORMANCE COOL ROOFS DAYLIGHTING AND CONTROLS NIGHT VENTING RENE WABLE ENERGY IDENTIFY DESIGN INTENT COMMUNIC ATING DESIGN INTENT MECHANIC AL SYSTEM DESIGN ENERGY CODE COMPLIANCE DEDIC ATED MECHANIC AL SYSTEMS D E M A N D CON T R O L V E N T I L AT I O N HOT WATER SYSTEM EFFICIENCY MINIMUM IAQ PERFORMANCE MECHANIC AL EQUIPMENT EFFICIENCY SUPPLY AIR TEMPER ATURE RESET VARIABLE SPEED CONTROL INDIRECT E VAPOR ATIVE COOLING ENERGY RECOVERY NIGHT VENTING DEMAND RESPONSIVE BUILDINGS RENE WABLE ENERGY HAS A ROLE IN THIS STR ATEGY HAS PRIMARY RESPONSIBILIT Y FOR THIS STR ATEGY
ARCHITECT
MECHANIC AL ENGINEER
INTRODUCTION ○ QUICK START GUIDE
B UI LDI NG MA NAG E R
C X AG E NT
UTILIT Y
OWNER
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ROLE OF PROJEC T TE AM ME MB ER S IN IMPLE MENTATION OF CORE PERFORMANCE PRO GR AM CRITERIA ( CONTINUED )
ME C HA NI C A L ENGINEER LI G HTI NG DESIGNER CON T R ACTOR OCCUPANTS
ARCHITECT
LIGHTING DESIGNER 1.1 1.2 2.1 2.7 2.8 3.2 3.3 1.1 1.6 2.13 2.2 2.3 3.9 IDENTIFY DESIGN INT ENT COMMUNIC ATING DESIGN INTENT ENERGY CODE COMPLIANCE LIGHTING CONTROLS LIGHTING POWER DENSIT Y DAYLIGHTING AND CONTROLS ADDITIONAL LIGHTING POWER REDUCTIONS IDENTIFY DESIGN INT ENT OP E R ATOR T R A I N I N G FUNDAMENTAL ECONOMIZER PERFORMANCE AIR BARRIER PERFORMANCE MINIMUM IAQ PERFORMANCE PREMIUM ECONOMIZER PERFORMANCE
CON T R ACTOR
COMMISSIONING AGENT 1.5 CONSTRUCTION CERTIFIC ATION 3.13 ADDITIONAL COMMISSIONING UTILIT Y REPRESENTATIVE 1.1 1.7 IDENTIFY DESIGN INT ENT PERFORMANCE DATA RE VIE W
BUILDING MANAGER 1 . 6 OP E R ATOR T R A I N I N G 1.7 PERFORMANCE DATA RE VIE W 3.11 DEMAND RESPONSIVE BUILDINGS OCCUPANTS 3.4 PLUG LOADS/APPLIANCE EFFICIENCY HAS A ROLE IN THIS STR ATEGY HAS PRIMARY RESPONSIBILIT Y FOR THIS STR ATEGY
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INTRODUCTION ○ QUICK START GUIDE
B UI LDI NG MA NAG E R
C X AG E NT
UTILIT Y
OWNER
Integration of Core Performance with USGBC LEED Program
The Core Performance program has been adopted by the USGBC as a prescriptive alternative to energy modeling to achieve up to five LEED points in the Optimize Energy Performance credit (EA credit 1). All LEED buildings are now required to achieve at least two points in this credit in order to achieve a LEED certification. Projects that implement the basic requirements of the Core Performance program (outlined in sections one and two of this Guide) achieve two or three LEED points. Three points are achieved by office, school, retail and public assembly project types, because the characteristics of these project types are most closely aligned with the Core Performance program. All other project types (except health care, labs and warehouses) can achieve two LEED points by following the basic requirements of the Core Performance program. Projects that use this program for LEED must be 100,000 square feet or smaller. The Core Performance program applies only to LEED for New Construction (LEED-NC) projects. All projects which achieve points as described above can achieve up to two additional LEED points in EAc1 by implementing additional energy conservation strategies from the Enhanced Performance Strategies (section three) of the Core Performance Guide. One additional point is achieved for each set of three additional strategies adopted. Note that the following strategies are not eligible for LEED points: 3.1 Cool Roofs 3.8 Night Venting 3.13 Additional Commissioning No more than two additional LEED EAc1 points can be achieved by implementing Enhanced Performance Strategies. In addition to the specific prescriptive energy points available in LEED, the Core Performance program requirements align with a number of other LEED credits. These relationships are identified in the table on the following page.
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
INTRODUCTION ○ INTEGRATION OF CORE PERFORMANCE WITH USGBC LEED PROGRAM
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ALIGNMENT O F CORE PERFORMANCE CRITERIA WITH LEED NC CREDITS*
CRITERIA
NA ME
EA
EAC1** EAP1 EAP2 EAP3 EAC5 EAC3 EAC2
EQ
EQC3.2 EQC8.1 EQC3.1 EQP1 EQC1
SS
SSC7.2
1. 2 1. 5 1. 6 1.7 2 .1 2.3 2.5 2.6 2 .7 2. 8 2 .9 2 .11 2 .12 3.1 3. 2 3. 3 3. 4 3. 5 3. 6 3.7 3. 8 3.10 3.12 3.13 4.1
COMMUNICATING DESIGN INTENT CO N S T R U C T I O N C E RT I F I C AT I O N OPER ATOR T R A I N I N G PERFORMANCE DATA RE VIE W E N E RGY CODE COM PL I A N CE M I N I M U M I AQ P E R F O R M A N C E OPAQUE ENVELOPE PERFORMANCE F E N E S T R AT I O N P E R F O R M A N C E L I G H T I N G CO N T R O L S LIGHTING POWER DENSIT Y MECHANICAL EQUIPMENT EFFICIENCY REQUIREMENTS D E M A N D CON T R O L V E N T I L AT I O N DOMESTIC HOT WATER SYSTEM EFFICIENCY COOL ROOFS DAYLIGHTING AND CONTROLS ADDITIONAL LIGHTING POWER REDUCTIONS PLUG LOADS/APPLIANCE EFFICIENCY SUPPLY AIR TEMPER ATURE RESET ( VAV ) INDIRECT E VAPOR ATIVE COOLING ENERGY RECOVERY NIGHT VENTING VARIABLE SPEED CONTROL ON-SITE SUPPLY OF RENE WABLE ENERGY AD DITIONAL COMMISSI ONING S TR ATEG IE S PREDIC T PERFO R M ANCE WITH ENERG Y MODELING
X X X X X X X X X X X X X X X X X X X X X X X X X
* This table identifies which LEED credits align with specific Core Performance Criteria. Alignment between the two standards does not imply that the language from one standard meets the requirements of the other. Individual requirements must be reviewed in the context of each standard. ** Measures listed contribute to improved energ y performance if LEED energ y modeling is conducted. Projects that do not undertake LEED energ y modeling achieve prescriptive default points in EA credit 1 as determined by the USGBC.
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INTRODUCTION ○ INTEGRATION OF CORE PERFORMANCE WITH USGBC LEED PROGRAM
Core Performance Program Outline
SEC TION 1 1.1 1. 2 1. 3 1. 4 1. 5 1. 6 1.7 SEC TION 2 2 .1 2.2 2.3 2.4 2.5 2.6 2 .7 2.8 2 .9 2 .10 2 .11 2 .12 2 .13 SEC TION 3 3.1 3. 2 3. 3 3. 4 3. 5 3. 6 3.7 3. 8 3.9 3.10 3.11 3.12 3.13 3.14 SEC TION 4 4.1 D E SIG N PRO C E SS S TR ATEG IE S IDENTIF Y DE SIG N INTENT CO MMUNIC ATING DE SIGN INTENT BUILD ING CO NFIGUR ATI O N MECHANIC AL S YS TEM DE SIGN CO NS TRUC TION CER TIFIC ATION ( ACCEP TANCE TE S TING ) O PE R ATO R T R AININ G AND D O C UM E N TATI O N PER F O R M AN C E DATA R E V I E W CO R E PER FO R MAN CE REQUIREMENT S ENERG Y CO DE CO MPLIANCE AIR BARRIER PERFOR M ANCE MINIMUM IAQ PERFOR M ANCE BELOW- G R AD E E X TERI O R INSUL ATI O N O PAQUE EN V ELO PE PERFO R M ANC E FENE S T R AT I O N PER FO R M AN C E LIGHTING CO NTROL S LIGHTING P OWER DENSIT Y MECHANIC AL EQUIPMENT EFFICIENC Y REQUIREMENT S DEDIC ATED MECHANIC AL S YS TEM S DEM AND CO NTROL V ENTIL ATION D O ME S TI C H OT WATER S YS TE M EFFIC IENC Y ECONOMIZER PERFOR M ANCE ENHANCED PERFOR M ANCE S TR ATEGIE S CO O L RO O FS DAY LIGHTING AND CO NTROL S ADDITIONAL LIGHTING P OWER REDUC TIONS PLUG LOADS / APPLIANCE EFFICIENC Y SUPPLY AIR TEMPER ATURE RE SE T ( VAV ) INDIREC T E VAP OR ATIVE CO OLING ENERG Y RECOV ERY NIG HT V ENTING PREMIUM ECONOMIZER VARIABLE SPEED CO NTROL DEM AND -RESP O NSIVE BUILDINGS ( PE AK P OWER REDUC TION ) ON-SITE SUPPLY OF RENE WABLE ENERG Y ADDITIO NAL CO MMISSIO NING S TR ATEG IE S FAULT D E TEC TI O N AND DIAG N OS TIC S ENERG Y MODELING PREDIC T PERFO R M ANCE WITH ENERG Y MO D ELING
Section One: Design Process Strategies
1.1 Identify Design Intent 1.2 Communicating Design Intent 1.3 Building Configuration 1.4 Mechanical System Design 1.5 Construction Certification (Acceptance Testing) 1.6 Operator Training and Documentation 1.7 Performance Data Review
Design Process Strategies
The Criteria in this section describe required steps for the design team to effectively implement the Core Performance program. These strategies provide a framework for successful design integration, and protocols to verify the intent, implementation, and outcome of the design process.
Introduction
1.1 Identify Design Intent
PURP OSE Develop consensus among the project team and owner as to the performance goals of the project and identify design strategies to achieve these goals. Ensure the design is developed in a way that meets the objectives of the building program including energy and environmental needs. Discuss Advanced Buildings Core Performance program requirements and identify implementation strategies. CRITERIA The project team, shall conduct a team meeting to identify key energy and environmental goals and principles. This meeting should consist of a facilitated discussion before the schematic design process has concluded. Discussion should include the identification of specific Core Performance strategies to be applied to this project, and how these strategies will be implemented. If the Core Performance program is initiated later in the design process, complete this step as soon as possible. Meeting participants should include all key project team members, including the following: Owner Architect Mechanical Engineer Electrical Engineer and/or Lighting Designer General Contractor (if selected) Utility Efficiency Program Representative (In Vermont: Efficiency Vermont, Burlington Electric Department and/ or Vermont Gas Systems Representative) Leasing Agent (if speculative development) Facilities Manager End User Representative
Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
As part of the goal-setting exercise, the energy performance target for the building should be defined as a score of 90 or higher using ENERGY STAR Target Finder. This should be documented by generating a Statement of Energy Design Intent using Target Finder. Include a copy of the meeting summary/goals statement and a copy of the Statement of Energy Design Intent Target Finder documentation in the project documentation described in Criteria 1.2.
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By following Core Performance, you may also qualify to display the “Designed to Earn the ENERGY STAR” graphic on qualified plans to show your commitment to creating buildings that perform better and prevent pollution. The following steps are necessary to qualify:
Join ENERGY STAR - become a Service and Product Provider partner. Use Target Finder to obtain the energy performance rating of your design — scores of 90 and higher qualify (part of Criteria 1.2) Print and complete the Statement of Energy Design Intent (SEDI) - this must include the project architect’s or engineer’s stamp. Print application letter on company letterhead and sign. Submit both documents to EPA. Receive “Designed to Earn the ENERGY STAR” graphic - place in title block next to the name of project-qualifying design.
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DESIGN PROCESS STRATEGIES ○ 1.1 IDENTIFY DESIGN INTENT
Introduction
1.2 Communicating Design Intent
PURP OSE Ensure the design intent and design performance Criteria are effectively documented and communicated through the design process and to the construction team to facilitate successful project operation. CRITERIA As part of the design process, the design team shall develop the five documents and components described below. All of the documentation described must be developed in the design phase described, updated as needed in each subsequent phase, and included in the final documentation package as part of the as-built documentation turned over to the project owner. A copy of this documentation should be included in the operations manual for the project.
1- DE SIGN INTENT MEE TING SUMM ARY
Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Develop a written summary of the outcomes of the Design Intent meeting described in Criteria 1.1. This summary should be used to guide subsequent decisions on design features and performance Criteria throughout the course of the design process. Also include a description of the building configuration options considered in Criteria 1.3, and a description of the preferred building configuration. Complete this document before the end of the schematic design phase. If the Core Performance program is initiated later in the design process, complete this documentation as soon as possible.
2- O PE R ATI O N AL PER FO R M AN C E R EQ UIR E M E N T S
This document identifies how the building is intended to operate. It should be developed as a narrative statement, before completion of the design development phase. The document should describe the following:
The operational performance goals, providing detailed explanation of the ideas, concepts and Criteria that the owner defines as important. A description of the Basis of Design of the systems including all information necessary to prepare a design to accomplish operational performance. A description of how the design team has minimized energy consumption and demand by first reducing loads to a minimum then designing an appropriate mechanical system to meet those loads through a range of operating conditions. A description of the Sequence of Operation of the systems and their interaction with other systems. A description of the systems, including the capacities and anticipated efficiency of the equipment or systems. A set of guidelines requiring that substitutions proposed in the construction process identify how the proposed substitution affects operational parameters described above. A copy of the Statement of Energy Design Intent indicating a score of 90 or higher using ENERGY STAR Target Finder.
The Thrivent Bank Building provides daylight control by using louvered overhangs to separate the clerestory and view glass. Photo courtesy
of Energy Center of Wisconsin
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3-ACCEP TANCE TE S TING REQUIREMENT S
An acceptance testing plan shall be prepared that specifies the process for meeting the owner’s project requirements. This document shall explain the process to be implemented to meet the requirements of Criteria 1.5-Construction Certification. The plan should be developed in the construction documents phase and included in the bid documentation as a project requirement. The document shall describe: A process to verify proper coordination among systems and assemblies, and between all contractors, subcontractors, vendors and manufacturers of furnished equipment and assemblies. A list of key equipment to be tested, and the construction phase in which testing is to occur. A description of the testing requirements and the passing Criteria to be used to ensure proper equipment operation and control. A list of test outcome documentation and forms necessary for review prior to final systems acceptance.
Additional information about acceptance testing requirements can be found in Criteria 1.5, Criteria 3.13, and in Appendix A. Note that acceptance testing is a form of commissioning that can be implemented by the construction team. The project owner may wish to consider the implementation of a full commissioning protocol using a third party provider.
4 - CO NS TRUC TION D O C UMENT S
The construction documents shall contain sufficient information to describe the envelope, including: air barrier; heating, ventilation, and air conditioning (HVAC); service hot water; lighting; electric power distribution systems; and system operational features and controls. All HVAC, lighting and electric power distribution system plans shall contain sufficient information to identify the system and equipment arrangements, system and equipment sizing, systems specifications, efficiency requirements and systems sequence(s) of operation. The construction documents shall demonstrate that tabulation of the building loads used assumptions consistent with the requirements of Core Performance or document why different assumptions were used. Specifications shall include narrative descriptions in each subsection that includes systems and equipment related to building energy performance. The narrative shall identify performance requirements for the equipment and systems and shall include a list of performance parameters that must be submitted with any proposed substitution request in the construction process. Design-Build projects with reduced documentation must still develop written performance Criteria that describe energy performance information used to select, size, and install equipment, including as-built information for building operators.
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DESIGN PROCESS STRATEGIES ○ 1.2. COMMUNICATING DESIGN INTENT
The construction documents shall require the submittal of operation manuals and maintenance manuals as a condition of final acceptance, including a description of their format and content. The operation manual shall provide all relevant information needed for day-to-day operation and management of each system. The maintenance manual shall describe equipment inventory and support the maintenance program. The submittal of record drawings and control documents are a condition of final acceptance. (Also see Criteria 1.6).
5-REQUIREMENT S FO R BID SUBMIT TAL S
The construction documents shall include specific requirements for Bid Submittals and Change Requests generated by the contractor. These requirements shall ensure that Bid Submittals contain comparative energy performance information so they can be reviewed to assure conformance with the Construction Documents. Changes shall be reviewed to assure they are consistent with the specific operational performance requirements and the statement of project goals and principles. “Or Equal” substitutions shall be shown to assure equal or better energy and indoor environmental performance when compared to the same element in the original construction document. Proposed changes that do not demonstrate equivalent energy performance shall not be considered Or Equal substitutions. If building energy performance assumptions are based on energy modeling (per Section Four of Core Performance), the impact of substitutions shall be re-simulated to demonstrate equivalent energy performance.
LEED Relationship SS WE EA MR EQ prereq 1
DESIGN PROCESS STRATEGIES ○ 1.2. COMMUNICATING DESIGN INTENT
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
1.3 Building Configuration
PURP OSE Consider building configurations to reduce building energy use by maximizing opportunities for daylighting, site shading, cross and stack ventilation and other passive features that maximize the opportunity for climatic-responsive design to reduce space conditioning loads. CRITERIA Develop and analyze at least three alternate building configuration designs that maximize the opportunity for passive strategies to reduce building energy loads. Consider the impacts of additional load-reduction strategies and passive-space conditioning opportunities to reduce building energy use. Document the advantages and disadvantages of each scheme considered in the Design Intent Documentation, as developed for Criteria 1.2. GENER AL Decisions about building configuration can have significant impacts on building energy use. Many resources are available to designers to help determine the impacts of building configuration alternatives on building energy use. Early-design whole-building energy analysis software or other evaluation tools can be used to compare the alternatives and determine potential savings without a significant investment in full-scale energy modeling. One way to accomplish this Criteria is to use the Green Building Studio™ web tool to quickly evaluate the performance implications of the building configurations. This tool uses CAD or building information modeling (BIM) data from architectural design software to predict energy performance using advanced modeling tools. The information generated by these tools can help to quickly determine the relative performance implications of different design schemes. Projects that use these tools may also continue to develop the analysis are described at www. advancedbuildings.net. Other tools that may prove useful in this kind of analysis include Energy Scheming and IES Virtual Environment.
By orienting the building on an east-west axis, the designers of the Cambria Of fice Building were able to maximize solar exposure while minimizing east - west window glare.
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Introduction
1.4 Mechanical System Design
PURP OSE Ensure that the mechanical system is designed to minimize energy consumption and maximize occupant comfort throughout the range of operating conditions. CRITERIA Employ best practices design techniques to improve system performance and meet ASHRAE Standard 55. The design engineer shall document the following actions in the design process:
Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
When sizing the heating and cooling equipment, perform load calculations using building shell and interior load assumptions that are consistent with Advanced Buildings Core Performance requirements. Include accurate characterization of lighting, solar loads, glazing performance, occupancy and ventilation loads based on specific design characteristics of this project. When sizing the fan and air distribution systems, document fan-sizing calculations with zone-by-zone load calculations. Perform calculations to determine critical path supply duct pressure loss. Compare fitting selections for the critical branch to minimize fan horsepower requirements. Utilize round or oval duct wherever feasible to lower leakage and reduce pressure loss, and avoid
FIGURE 1.4.1
It is critical that the cumulative effect of energ y efficiency measures in reducing cooling and heating loads be reflected in equipment sizing to capture first-cost savings.
37
high-pressure duct systems where possible. Separate all fittings in medium- and high-pressure duct work by several duct diameters to reduce system effects wherever feasible. Use relief fans in lieu of return fans where possible, and provide automatic dampers on exhaust in lieu of barometric dampers to reduce fan power and increase barometric relief.
Perform a second set of calculations using part-load conditions (maximum likely load and/or standard operating conditions). This includes using benchmark data, average daytime temperatures and non-peak solar gain, and other assumptions to define part-load conditions for the heating and cooling system. Include diversity factors for interior loads and other factors that will allow proper assessment of part-load operation. Describe the system operation at these conditions and describe features of the design that will facilitate efficient operation at these part-load conditions. Document in Criteria 1.2 how the system will deliver ventilation air, maintain comfort in accordance with ASHRAE Standard 55 and operate in an energyefficient manner.
The design practices described above will lead to installed system capacities that more closely match actual building loads. This reduces installed excess system capacity, reducing equipment first costs. By sizing the system more closely to the actual building loads, the system operating characteristics more closely match the efficiency curves and performance characteristics anticipated in manufacturer data. This increases operating efficiency, reduces operating costs, and extends equipment service life. Additional savings can be achieved by adopting the adaptive comfort standards described in ASHRAE Standard 55.
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DESIGN PROCESS STRATEGIES ○ 1.4. MECHANICAL SYSTEM DESIGN
Introduction
1.5 Construction Certification (Acceptance Testing)
PURP OSE Ensure that the design is constructed and operates as intended by the construction documents by testing and verifying system performance. CRITERIA The construction process shall be conducted to deliver a building that meets or exceeds the requirements of the owner, as identified in the Operational Performance Requirements and the acceptance testing plan developed under Criteria 1.2, and in the construction documents. This process shall include the following:
Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Acceptance testing shall be performed on the following equipment, if installed:
Outdoor Air Systems Air Distribution Systems Hydronic Systems VAV Systems Package Rooftop Units Economizers Chilled Water Systems Demand Control Ventilation Systems Automatic Daylighting Controls Automatic Time-of-Day Controls Occupancy Sensors Building Control Systems
Change-orders shall be reviewed to assure they are consistent with the operational performance requirements and statement of goals and principles. Or-equal substitutions shall be shown to assure equal or better energy and indoor environmental performance when compared to the original certified design. If using an energy modeling approach to Core Performance (per Section Four), the substitutions shall be re-simulated to demonstrate equivalence to the modeled savings anticipated.
The installing contractor(s), engineer of record or owner’s agent shall certify that the procedures listed in Appendix A were performed and the equipment performed as specified. For equipment not listed above, the design team shall provide acceptable test results and the contractor shall certify that the tests were performed and the equipment performs as specified. An acceptance testing report shall be prepared documenting the results of the construction process including: Deficiencies found during testing required by this section that have not been corrected at the time of report preparation and the anticipated date of correction. Deferred tests that cannot be performed at the time of report preparation due to climatic conditions. Climatic conditions required for performance of the deferred tests, and the anticipated date of each deferred test. Complete the Construction Certification prior to requesting a fi nal occupancy permit (but not necessarily before temporary occupancy).
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FIGURE 1. 5.1
The graph above, compiled from a number of field studies, shows how frequently performance aspects of newly installed rooftop HVAC equipment was found to be defective. Note that the economizers on an astonishing 70% of rooftop units less than five years old are either missing or inoperative! GENER AL The Construction Certification documents demonstrate that the installing contractor, engineer of record or owner’s agent:
Reviews the installation Performs acceptance tests and documents results Documents the operating and maintenance information and test results on the Construction Certification
LEED Relationship SS WE EA MR EQ prereq 1
The installing contractor, engineer of record or owner’s agent shall be responsible for documenting the results of the acceptance requirement procedures including paper and electronic copies of all measurement and monitoring results. They shall be responsible for performing data analysis, calculation of performance indices and crosschecking results with the requirements of the Core Performance. The installing contractor, engineer of record, or owner’s agent, upon completion of undertaking all required acceptance requirement procedures, shall record their contractor’s license number, Professional Registration License Number, or other professional identification on each Certificate that they issue. The building owner may decide to use a third party commissioning agent to conduct this work, as described in Criteria 3.13.
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DESIGN PROCESS STRATEGIES ○ 1.5 CONSTRUCTION CERTIFICATION (ACCEPTANCE TESTING)
Introduction
1.6 Operator Training and Documentation
PURP OSE Ensure that the building operations team understands how the building is intended to operate and has the resources to monitor and understand building operational characteristics. CRITERIA Complete an Operator Training program and provide full documentation of building characteristics, equipment, operation, control, maintenance and monitoring protocols. Verify that the following steps were taken before occupancy:
Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Operator training was performed by the building construction and design team. Systems manuals and a full set of design and installation documents were delivered and accepted by the building operations team. Appropriate maintenance schedules and calibration requirements were included in the operations manual. Information is developed and provided describing building user interface with lighting, ventilation and temperature controls. Control and data collection protocols were set up and understood by the building operations team.
Building specific information should be gathered and turned over to the building operations team. This information should not be limited to manufacturer information about installed equipment but should also include descriptions of system operation and maintenance procedures and a full set of design documents. A narrative describing design intent and building operation protocols should be included, with information about control system operation. Maintenance schedules and part reordering information should also be included. All of this information should be well organized and tabbed, so that building operators can use the manuals as a reference. Consider video recording the training for future reference. Operator training should include a formal walk-through and training session to give the building operations team hands-on experience with the topics discussed, and to allow the opportunity for operators to ask questions of the installation team. Operator training should include information about the monitoring capabilities and protocols built into the project (see Criteria 1.7). Systems manuals should include a description of the datacollection protocols that will be used to verify system performance and the frequency with which this information will be gathered and reviewed. Over time, reports of building monitoring and maintenance activities should also be included in the operations manuals.
LEED Relationship SS WE EA MR EQ credit 3
Even relatively simple building control systems may now include digital interface for building operators.
41
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
1.7 Performance Data Review
PURP OSE Assure the persistent delivery of energy and environmental benefits from the building by collecting and reviewing on-going energy performance data. CRITERIA Implement a protocol to collect and analyze energy use, and building occupancy information. Review and update this information at least quarterly, and include a quarterly summary report in the building operations manual. Data collection requirements include these elements:
Hourly metered electric and fuel use data. Information on typical occupant use patterns and building hours of use, updated regularly.
Power density charts which track energ y use per square foot allow quick identification of operating anomolies.
Specific metering equipment (pulse meters) must be installed to generate the hourly energy consumption data. Hourly data from metered energy use should be collected by an automatic data collection system with data logging and communication capacity. The data is sent to a database which will also collect local temperature information from a regional site and generate a quarterly report on building performance. This report should be reviewed by the building operations team, compared with updated occupant use patterns, and included in the building operations manual for periodic reference. Information about specific protocols and equipment which can be used to achieve this Criteria is available in the reference section at www.advancedbuildings.net. The site also includes additional information about reporting and review protocols, building benchmarking, and other guidelines for implementing this Criteria. GENER AL
LEED Relationship SS WE EA MR EQ credit 5
Daily and annual energy consumption patterns reflect the true energy performance of a building. While the Core Performance program is designed to deliver a building with energy-efficient features, the overall energy performance of the facility may be affected by unanticipated factors. To ensure the building is performing to design level, this Criteria requires the gathering and review of actual building energy consumption to identify potential issues. Meaningful diagnostic information can be obtained by comparing energy use, outdoor temperature, and building use over time. While a complete picture of building performance will not emerge until after a full year of seasonal data has been collected, review of the data from the very beginning of operations can help identify and diagnose performance issues. The information gathered in this process can also be used to compare the building to others of similar type, use, and climate.
42
Section Two: Core Performance Requirements
2.1 Energy Code Compliance 2.2 Air Barrier Performance 2.3 Minimum IAQ Performance 2.4 Below-Grade Exterior Insulation 2.5 Opaque Envelope Performance 2.6 Fenestration Performance 2.7 Lighting Controls 2.8 Lighting Power Density 2.9 Mechanical Equipment Efficiency Requirements 2.10 Dedicated Mechanical Systems 2.11 Demand Control Ventilation 2.12 Domestic Hot Water System Efficiency 2.13 Fundamental Economizer Performance
Core Performance Requirements
All of the Criteria listed in this section are required components of the Core Performance program. Energy savings projections are based on the implementation of all applicable measures in this section.
Introduction Design Process Strategies
2.1 Energy Code Compliance
PURP OSE Define minimum level of acceptable performance for measures not specified in Core Performance. CRITERIA All buildings shall meet or exceed applicable state and local energy codes. Where state and local codes are not as stringent as ASHRAE 90.1-2004 requirements, features of building elements not described in Core Performance shall meet or exceed ANSI/ASHRAE/IESNA Standard 90.12004 or the International Energy Conservation Code (IECC) 2006. In Vermont, all buildings shall meet or exceed the Vermont Commercial Energy Code.
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Photo courtesy of DOE\NREL.
LEED Relationship SS WE EA MR EQ prereq 2
45
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.2 Air Barrier Performance
PURP OSE Reduce uncontrolled air movement through the building envelope. CRITERIA The building envelope shall be designed and constructed with a continuous air barrier system to control air leakage into or out of the conditioned space. An air barrier system shall also be provided for interior separations between conditioned space and space designed to maintain temperature or humidity levels which differ from those in the conditioned space by more than 50% of the difference between the conditioned space and design ambient conditions. The air barrier system shall have the following characteristics:
It must be continuous, with all joints made airtight. Materials used for the air barrier system shall have an air permeability not to exceed 0.004 cfm/ft2 under a pressure differential of 0.3 in. water (1.57psf) (0.02 L/s.m2 @ 75 Pa) when tested in accordance with ASTM E 2178.
Attention to detail is critical at all joints and penetrations to assure a complete air barrier.
Detail: Courtesy of the state of Massachusetts and Wagdy Anis, FAIA.
46
It shall be capable of withstanding positive and negative combined design wind, fan and stack pressures on the envelope without damage or displacement, and shall transfer the load to the structure. It shall not displace adjacent materials under full load. It shall be durable or maintainable. The air barrier material of an envelope assembly shall be joined in an air-tight and flexible manner to the air barrier material of adjacent assemblies, allowing for the relative movement of these assemblies and components due to thermal and moisture variations, creep and structural deflection. Verify that the sequence of construction allows for the installation of a continuous air barrier. All ducts in unconditioned spaces should be sealed at joints with mastic. Connection shall be made between:
Foundation and walls. Walls and windows or doors. Different wall systems. Wall and roof. Wall and roof over unconditioned space. Walls, floor and roof across construction, control and expansion joints. Walls, floors and roof to utility, pipe and duct penetrations.
All penetrations of the air barrier system and paths of air in fi ltration/exfi ltration shall be made airtight.
CORE PERFORMANCE REQUIREMENTS ○ 2.2.AIR BARRIER PERFORMANCE
47
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.3 Minimum IAQ Performance
PURP OSE Provide building occupants with acceptable indoor air quality. CRITERIA Design and operate the building to meet or exceed ASHRAE Standard 62-2004. This includes:
Design and implement an ASHRAE Standard 62 compliant outdoor air control technique. Develop and implement an IAQ Construction Management Plan to control contaminants and dust during construction. Flush the building with 100% of the scheduled quantity of outdoor air prior to occupancy and after punch list is complete. Develop and implement an IAQ Operations Management Plan for building operation.
Maintaining outside air volumes is more straightforward in constant volume systems than in VAV systems. Additional information about OA control options for VAV systems can be found at www.advancedbuildings.net.
Clackamas High School, Oregon.
Photo by Michael Mathers
LEED Relationship SS WE EA MR EQ prereq 1 credit 3.1 credit 3.2
48
Introduction Design Process Strategies
2.4 Below-Grade Exterior Insulation
PURP OSE Decoupling the temperature of slab-on-grade or below-grade masonry from the temperature of the ground reduces the potential for condensation on those surfaces. CRITERIA Slab-on-grade floors and below-grade floors and walls shall be isolated from ground temperatures with a minimum R-5 layer of rigid insulation (R-10 in Vermont) on the exterior side of the construction for all buildings located in climate zones designated “A” (moist) on the climate zone map (next page), and when any of the following applies:
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
buildings designed specifically for youth and elderly populations, buildings that have planned periods of greater than seven days when mechanical systems are shut down, or buildings that do not have a mechanical system maintaining the dewpoint temperature of the indoor air below the temperature of the indoor slab on grade or below-grade floor or belowgrade wall. Caution: This is a minimum requirement designed to alleviate some moisture condensation on these surfaces in many buildings; however, R-5 insulation may not be sufficient in all situations. Some local codes require insulation levels beyond this Criteria. The Vermont Commercial Energ y Code requires R-10 insulation. The San Mateo County Sheriff’s Forensic Laboratory and Cororner’s Of fice in San Mateo, California.
Courtesy of Hellmuth, Obata & Kassabaum
The greater of the insulation required according to this requirement or the insulation required according to the Opaque Envelope Performance (Criteria 2.5) shall be installed; the requirements are not additive. Note: Buildings located outside of the humid climate designation should isolate slab-on-grade floors and belowgrade floors and walls from ground temperatures with a minimum R-5 layer of rigid insulation on the exterior side of the construction where indoor environmental quality is a concern. The Vermont Commercial Energ y Code requires R-10 insulation.
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.5 Opaque Envelope Performance
PURP OSE Reduce environmental impacts and increased operational costs associated with thermal conductance through the building envelope. CRITERIA Walls, roof assemblies, floors and slabs-on-grade which are part of the building envelope for buildings where window and glazed door area is not greater than 40% of the gross area of above-grade walls shall meet the Criteria shown in Table 2.5.1. Buildings with window and glazed area greater than 40% of gross wall area must demonstrate achievement of equivalent energy performance with energy modeling. Energy modeling requirements are described in Section Four. The climate map below indicates which zone designation should be used in determining envelope and fenestration performance requirements. A more detailed version of this map is located in Appendix B. Additional information about envelope performance strategies can be found in the reference materials on Envelope Performance Criteria Advisory at www.advancedbuildings.net. FIGURE 2. 5.1 - CLIM ATE ZONE M AP
Climate Zones are defined primarily by heating or cooling loads, than by type (Marine, Dry, Moist), creating a set of climate bands spanning the country.
LEED Relationship SS WE EA MR EQ credit 1
50
TABLE 2. 5.1 – MINIMUM INSUL ATION REQUIREMENT R-VALUE S This table is subject to continuous maintenance. This is table version 2007-1. Check www.advancedbuildings.net for updates. Contact Efficiency Vermont for updates on the Vermont Climate Zone.
C L IM AT E ZO NE R O O FS
Insulation Entirely above Deck Metal Buildings (with R-5 thermal blocks1) Attic and Other 2, 3
R-20 ci R-13 + R-19 R-38 R-5.7 ci4 R-114 R-6 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci NR 6 NR NR R-13 R-13 R-20 ci R-13 + R-19 R-38 R-5.7 ci4 R-114 R-6 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci NR 6 NR R-5 ci R-30 R-30 R-20 ci R-13 + R-19 R-38 R-7.6 ci4 R-114 R-6 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci NR 6 NR R-10 ci R-30 R-30 R-25 ci R-19 + R-13 R-382 R-7.6 ci R-13 R-10 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci R-7.5 ci 6 R-19 R-10 ci R-30 R-30 R-25 ci R-19 + R-13 R-382, 3 R-11.5 ci R-13 R-10 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci R-7.5 ci 6 R-19 R-10 ci R-30 R-30 R-30 ci R-30 + R-6 ci R-492, 3 R-11.5 ci R-19 R-10 + R-13 R-13 + R-5 ci R-13 + R-3.8 ci R-7.5 ci 6 R-19 R-10 ci R-38 R-30 R-24 ci R-19 + R-10 (with R-5 thermal blocks) or R-30 (with R-5 thermal blocks) R-38 R-9.5 ci R-9.5 ci R-19 or R-6 + R-13 R-13 + R-7.5 ci R-19 or R-12 ci or R-13 + R-3.8 ci R-10 ci R-10 ci R-10 ci R-30 R-30 R-35 ci R-19 + R-10 + R-10 ci R-492, 3 R-15 ci R-19 R-10 + R-13 R-13 + R-7.5 ci R-13 + R-5 ci R-10 ci 6 R-21 R-15 ci R-38 R-30 R-35 ci R-19 + R-10 + R-10 ci R-492, 3 R-15 ci R-19 R-10 + R-13 R-13 + R-14 ci5 R-13 + R-14 ci R-10 ci 6 R-21 R-15 ci R-38 R-30
1
2
3
4
5
6
VERMONT
7
8
WALL S, AB OV E GR ADE
Mass, exterior insulation 4 Mass, interior insulation Metal Building Metal Framed 5 Wood Framed and Other
4
WALL S, BELOW GR ADE
Mass, exterior insulation 6 Mass, interior insulation 6
FLO O R S
Mass Metal Joist Wood Joist/Framing
SL AB - O N - G R AD E FLO O R S
Unheated Slabs
NR R-7.5 for 12 in. + R-5 ci below NR R-7.5 for 12 in. + R-5 ci below NR R-7.5 for 12 in. + R-5 ci below R-10 for 24 in. R-10 for 24 in. + R-5 ci below R-10 for 24 in. R-15 for 36 in. + R-5 ci below R-10 for 24 in. R-15 for 36 in. + R-5 ci below R-10 for 48 in. R-15 for 24 in. + R-5 ci below R-20 for 36 in. + R-5 ci below R-15 for 24 in. + R-5 ci below R-20 for 36 in. + R-5 ci below
Heated Slabs
R-10 for entire slab (under slab and perimeter)
O PAQUE D O O R S
Swinging Roll-up or Sliding
U – 0.61 R-4.75 U – 0.61 R-4.75 U – 0.61 R-4.75 U – 0.61 R-4.75 U – 0.37 R-4.75 U – 0.37 R-4.75 NR R-10 U – 0.37 R-4.75 U – 0.37 R-4.75
Some local jurisdictions have requirements that exceed certain values here. Cross reference these insulation requirements with local requirements and guidelines. C I – C O N T I N U O U S I N S U L AT I O N NR – N O R E Q U I R E M E N T
1 2
Thermal blocks are an R-5 of rigid insulation, which extends 1” beyond the width of the purlin on each side, perpendicular to the purlin. Where vapor permeable insulation is used in climate zones 4 and above, the temperature of any condensation plane should be kept above the dew point of the internal air, as described in the text above. In any attic-type space, where insulation is blown or sprayed into the cavity, an additional R-11 of insulation is required in climate zones 5 and above. Un fi nished mass walls with a Heat Capacity greater than 12 Btu/ft2*F in climate zones 1, 2, 3-marine, and 3-dry do not need to be insulated. Additionally, if a mass wall with a Heat Capacity greater than 12 Btu/ft 2*F in climate zones 1 and 2 is fi nished only on the interior, no insulation is needed. R-10 continuous rigid insulation should be used in regions with greater than 14500 HDD65. When heated slabs are placed below grade, below grade walls must meet the exterior insulation requirements for perimeter insulation according to the heated Slab-on-Grade construction.
3 4
5 6
CORE PERFORMANCE REQUIREMENTS ○ 2.5. OPAQUE ENVELOPE PERFORMANCE
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TABLE 2. 5. 2 – M A XIMUM INSUL ATION U - FAC TOR S, C- FAC TOR S, AND F- FAC TOR S
CLIM ATE ZO NE R O O FS
Insulation Entirely above Deck Metal Buildings (with R-5 thermal blocks1) Attic and Other 2, 3
1
U – 0.048 U – 0.049 U – 0.027
2
U – 0.048 U – 0.049 U – 0.027
3
U – 0.048 U – 0.049 U – 0.027
4
U – 0.039 U – 0.047 U – 0.027 2
5
U – 0.039 U – 0.047 U – 0.0272, 3
6
U – 0.032 U – 0.039 U – 0.0212, 3
VERMONT
7
U – 0.028 U – 0.034 U – 0.0212, 3
8
U – 0.028 U – 0.034 U – 0.0212, 3
U-0.040 U-0.051 U-0.027
WALL S, ABOV E G R AD E
Mass, exterior insulation 4 Mass, interior insulation Metal Building Metal Framed 5 Wood Framed and Other
4
U – 0.142 4 U – 0.094
4
U – 0.142 4 U – 0.094 4 U – 0.070 U – 0.077 U – 0.064
U – 0.110 U – 0.094 4 U – 0.070 U – 0.077 U – 0.064
U – 0.110 U – 0.085 U – 0.061 U – 0.077 U – 0.064
U – 0.078 U – 0.085 U – 0.061 U – 0.077 U – 0.064
U – 0.078 U – 0.060 U – 0.061 U – 0.077 U – 0.064
U-0.104 U-0.104 U-0.070 U-0.064 U-0.064
U – 0.061 U – 0.060 U – 0.061 U – 0.064 U – 0.059
U – 0.061 U – 0.060 U – 0.061 U – 0.045 5 U – 0.038
U – 0.070 U – 0.077 U – 0.064
WALL S, BELOW G R AD E
Mass, exterior insulation 6 Mass, interior insulation 6
NR 6 NR NR U – 0.069 U – 0.066 NR 6 NR U – 0.123 U – 0.038 U – 0.033 NR 6 NR U – 0.076 U – 0.038 U – 0.033 C – 0.119 6 C – 0.063 U – 0.076 U – 0.038 U – 0.033 C – 0.119 6 C – 0.063 U – 0.076 U – 0.038 U – 0.033 C – 0.119 6 C – 0.063 U – 0.076 U – 0.032 U – 0.033 C-0.092 C-0.092 U-0.074 U-0.038 U-0.033 C – 0.092 6 C – 0.060 U – 0.055 U – 0.032 U – 0.033 C – 0.092 6 C – 0.060 U – 0.055 U – 0.032 U – 0.033
FLO O R S
Mass Metal Joist Wood Joist / Wood Frame
SLAB-ON-GRADE FLOORS
Unheated Slabs Heated Slabs
NR F – 0.70 U – 0.61 U – 0.53 NR F – 0.70 U – 0.61 U – 0.53 NR F – 0.70 U – 0.61 U – 0.53 F – 0.54 F – 0.65 U – 0.61 U – 0.53 F – 0.54 F – 0.58 U – 0.37 U – 0.53 F – 0.54 F – 0.58 U – 0.37 U – 0.53 F-0.64 F-0.55 U-0.50 NR F – 0.40 F – 0.55 U – 0.37 U – 0.53 F – 0.40 F – 0.55 U – 0.37 U – 0.53
O PAQUE D O O R S
Swinging Roll-up or Sliding
Assembly U-Factors, C-Factors and F-Factors based on ASHR AE 90.1-2001 Normative Appendix A (Assembly factors in Vermont are based on the Vermont Commercial Energ y Code) Some local jurisdictions have requirements that exceed certain values here. Cross reference these insulation requirements with local requirements and guidelines. NR – NO REQUIREMENT
1 2
Thermal blocks are an R-5 of rigid insulation, which extends 1” beyond the width of the purlin on each side, perpendicular to the purlin. Where vapor-permeable insulation is used in climate zones 4 and above, the temperature of any condensation plane should be kept above the dew point of the internal air, as described in the text above. In any attic-type space, where insulation is blown or sprayed into the cavity, an additional R-11 of insulation is required in climate zones 5 and above. Un fi nished mass walls with a Heat Capacity greater than 12 Btu/ft2*F in climate zones 1, 2, 3-marine, and 3-dry do not need to be insulated. Additionally, if a mass wall with a Heat Capacity greater than 12 Btu/ft 2*F in climate zones 1 and 2 is fi nished only on the interior, no insulation is needed. R-10 continuous rigid insulation should be used in regions with greater than 14500 HDD65. When heated slabs are placed below grade, below-grade walls must meet the exterior insulation requirements for perimeter insulation according to the heated slab-on-grade construction.
3 4
5 6
Reprinted by permission of American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., from ANSI/ASHR AE/IESNA Standard 90.1-2001. Copyright 2001 ASHR AE (www.ashrae.org).
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CORE PERFORMANCE REQUIREMENTS ○ 2.5. OPAQUE ENVELOPE PERFORMANCE
Introduction Design Process Strategies
2.6 Fenestration Performance
PURP OSE Promote the installation of high-performance glazing systems, and the use of a consistent performance rating standard for these products. CRITERIA Window systems which are part of the building envelope for buildings where window and glazed door area is not greater than 40% of the gross area of above-grade walls shall meet the Criteria shown in Table 2.6.1. Each vertical fenestration system must meet the U-Factor, the SHGC for the corresponding projection factor, and the VLT specification. Skylight systems which are a part of the roof assembly where the skylight area is not greater than 5% of the gross roof area shall meet the Criteria shown in Table 2.6.2. Each horizontal fenestration system must meet the U-factor and the SHGC. Note: Buildings where window and glazed door area is greater than 40% of the gross area of above-grade walls or skylight area is greater than 5% of the gross roof area must conduct energ y modeling to demonstrate equivalent performance. All fenestration (windows, skylights and doors) must be rated according to the requirements of the National Fenestration Rating Council (NFRC) with respect to the performance of the fenestration in the categories of U-value, Solar Heat Gain Coefficient and Visible Light Transmittance, and air leakage rate. NFRC ratings account for the performance of the frame/ mullion/spacer/glazing system as a whole.
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
FIGURE 2.6.1
Selective coatings are commonly used on glazing units to “tune” the glass to allow preferred wavelengths of light through but reflect unwanted solar heat. These coatings also help buildings retain heat in winter. The illustration shows glazing with SHGC=.30 and VLT=.72.
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CRITERIA SPECIFIC ATIONS : TABLE 2.6.1 – WIND OWS ( M A X . 4 0 % W WR OR LE SS ) full assembly (i.e not just glass by itself or each pane of glass)
CLIM ATE ZO NE OTHER FR A ME PRO DUC T S U - FAC TO R SHGC : AN Y PF ME TAL FR A MED PRO DUC T S U - FAC TO R SHGC : PF < 0. 25 SHGC : 0. 25< PF< 0. 5 SHGC : PF > 0. 5 ALL PRO DUC T S
(Daylight glazing only)
1
2
3
4
dry/ marine
4
humid
5
dry
5
humid
6
dry
6
humid
VT
7
8
0.57 0.40
0.57 0.40
0.40 0.40
0.35 0.40
0.40 0.40
0.35 0.40
0.35 0.40
0.35 0.40
0.35 0.40
0.35 0.40
0.35 Any
0.35 Any
0.57 0.24 0.32 0.39
0.57 0.24 0.32 0.39
0.5 0.24 0.32 0.39
0.42 0.24 0.32 0.39
0.45 0.24 0.32 0.39
0.42 0.30 0.39 0.39
0.45 0.30 0.39 0.39
0.42 0.30 0.39 0.39
0.45 0.30 0.39 0.39
0.45* 0.30 0.39 0.39
0.35 0.49 0.49 0.49
0.35 0.49 0.49 0.49
V LT / SHG C R ATI O
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
> 1.5
* In Vermont, Curtain Wall/Storefront U-Factor = 0.40
SHGC = S OL AR HE AT G AIN CO EFFICIENT PF = PRO J EC T I O N FAC TO R V LT = V ISIBLE LIG HT TR ANSMIT TANCE
TABLE 2.6. 2 – SK Y LIGHT S ( M A X 5 % OF RO OF ARE A OR LE SS )
CLIM ATE ZO NE 1 2 3 4 5 6 VT 7 8
FAC TO R Y A SS E M BLED FENE S T R AT I O N PRO D UC T S* U - FAC TO R SHGC G L A SS, N O C U R B U - FAC TO R SHGC V LT / SHG C R ATI O GL A SS, WITH CURB U - FAC TO R SHGC V LT / SHG C R ATI O
0.71 0.19 > 1.25 0.71 0.19 > 1.25 0.71 0.19 > 1.25 0.71 0.32 > 1.25 0.67 0.36 > 1.25 0.67 0.46 > 1.25 0.60 0.40 > 1.25v 0.67 0.46 > 1.25 0.67 0.46 > 1.25 0.57 0.40 0.57 0.40 0.45 0.40 0.45 0.40 0.45 0.40 0.45 0.40 0.45 0.40 0.45 Any 0.45 Any
0.57 0.19 > 1.25
0.57 0.19 > 1.25
0.57 0.19 > 1.25
0.57 0.32 > 1.25
0.54 0.36 > 1.25
0.54 0.46 > 1.25
0.54 0.40 > 1.25
0.54 0.46 > 1.25
0.54 0.46 > 1.25
LEED Relationship SS WE EA MR EQ credit 1
Reprinted by permission of American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., from ANSI/ASHR AE/IESNA Standard 90.1-2001. Copyright 2001 ASHR AE (www.ashrae.org).
*Skylight products designed to actively harvest daylighting with tracking collectors, refl ectors, etc. must meet U-value requirements, but are exempt from the SHGC and VT requirements listed.
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CORE PERFORMANCE REQUIREMENTS ○ 2.6. FENESTRATION PERFORMANCE
Introduction Design Process Strategies
2.7 Lighting Controls
PURP OSE To reduce lighting energy use through the installation of automatic lighting controls and adjustable lighting level strategies. CRITERIA All areas of the building must incorporate the following three switching and control strategies:
1- B I - L E V E L S W I TC H IN G
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
The installed control device(s) shall allow the occupants to reduce the connected lighting load in a reasonably uniform illumination pattern by at least 50% (or at least 40% for HID luminaries).
2-SE PAR AT E S W I TC H I N G AT DAY L I T A R E A S
Daylit areas of the building must be separately controlled from non-daylit areas of the building using separate switching, regardless of whether automatic daylight controls are installed. If automatic daylight controls are not installed in these areas, the switching in daylit areas must be capable of reducing lighting levels by 50% and 100% so that occupants may respond to changing daylight levels. Daylit areas are generally considered to be those within 1.5 times the ceiling height of the building perimeter, and those areas within 0.75 times the ceiling height distance beyond the edge of skylight wells.
3 -AU TOM AT I C CO N T R O L S
Automatic lighting controls must be installed throughout the building to reduce lighting energy use. Automatic controls may include occupancy sensors, automatic daylight controls or time clock controls, as described below. (Occupancy sensors must be installed in the specific areas identified in that section below.) Controls must be installed in all areas of the building except those listed at the end of this Criteria. In addition to the control strategies below, all building areas must also meet the automatic control requirements listed in ASHRAE 90.1-2004 Section 9.4.1. In Vermont, all building areas must also meet the automatic control requirements listed in the Vermont Commercial Energy Code Section 805.2 Lighting Controls. Acceptable Automatic Control Strategies:
A - O CC U PAN C Y S E N S O R S
Occupancy sensors must be installed in all classrooms, conference/meeting rooms, employee lunch and break rooms, private offices, restrooms, storage rooms and janitorial closets, and other spaces 300 sf. or less enclosed by ceiling height partitions. These automatic control devices shall be installed to automatically turn off lights within 30 minutes of all occupants leaving the space, except spaces with multi-scene control. Additional space types may be appropriate for these controls and should be evaluated on a case-by-case basis. Open office areas can be served by ceiling mounted occupancy sensors in many cases. Areas where automatic daylight controls are installed are not required to have occupancy sensors in addition to the daylight controls, although integrated or dual controls may be implemented for additional energy savings.
55
B - AUTOM ATIC DAY LIGHT CO NTROL S
Where automatic daylight controls are installed, they should meet the following Criteria:
Control the lights in the daylit areas separately from the non-daylit areas. Automatically reduce electrical lighting power in response to available daylight in a daylit area by either: Continuous dimming using a combination of dimming ballasts and daylight-sensing automatic controls that are capable of automatically reducing the power of general lighting in the daylit zone continuously to less than 35% of rated power at maximum light output. Stepped dimming using a combination of multi-level switching and daylight-sensing controls that are capable of reducing the lighting power automatically. The system should provide at least two control channels per zone and be installed in a manner such that at least one control step shall reduce power of general lighting in the daylit zone by 30 to 50% of rated power and another control step shall reduce lighting power by 65 to 100%. This control shall be capable of automatically reducing the general lighting in the daylit area in multiple steps in response to available daylight while maintaining a reasonably uniform and appropriate level of illuminance. Stepped dimming is not appropriate in continuously occupied areas with ceiling heights below 14 ft.
FIGURE 2.7.1
Occupancy sensors can save substantial amounts of energ y by turning lights off when a space is unoccupied. This chart demonstrates the additional energ y savings potential in a classroom using occupancy sensors compared to a baseline of timeclock controls.
56
CORE PERFORMANCE REQUIREMENTS ○ 2.7. LIGHTING CONTROLS
Each daylight control zone shall not exceed 2,500 square feet. The controls for calibration adjustments to the lighting control device shall be readily accessible to authorized personnel.
C - TIME CLO CK CO NTROL S
Automatic control may be accomplished by scheduled time clock controls for areas not requiring occupancy sensors, including occupied open areas such as open office and retail sales floor where partitions and obstructions may impact the effectiveness of occupancy sensors. These areas should include clearly marked override switches which bypass the time clock for increments of no longer than four hours. These areas should be evaluated on a case-by-case basis to determine if occupancy sensors can be utilized before a time clock system is selected to control these areas. Exceptions to Automatic Control Requirements:
Lighting required by a health or life safety statute, ordinance or regulation, including but not limited to emergency lighting. Lighting for theatrical purposes, including performances, stage, fi lm production and video production. Lighting intended for 24-hour operation. Emergency lighting. Corridors enclosed with floor-to-ceiling height partitions shall have no more than 50% of the luminaires on an automatic shutoff control device. Public lobbies. Health care patient rooms. Lighting for industrial production.
LEED Relationship SS WE EA MR EQ credit 1
CORE PERFORMANCE REQUIREMENTS ○ 2.7. LIGHTING CONTROLS
57
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.8 Lighting Power Density
PURP OSE Reduce environmental impacts and increased operational costs associated with energy consumption of lighting systems. CRITERIA Installed lighting equipment power density shall not exceed the allowed lighting equipment power density (LPD) as shown in Table 2.8.1. These LPD’s should be calculated based on fixture efficiency, including lamps and ballasts. TABLE 2. 8.1 - INTERIOR LIGHTING P OWER This table is subject to continuous maintenance. This is table version 2007-1. Check www.advancedbuildings.net for updates. Contact Efficiency Vermont for updates to the Vermont Edition.
For use types not shown, follow LPD requirements of ASHRAE 90.1-2004. For a description of how to apply ‘whole building’ vs. ‘spaceby-space’ calculation Criteria, see ASHRAE 90.1-2004 sections 9.5.1 and 9.6.1. In Vermont, see the Vermont Commercial Energ y Code Section 805.5.2 Interior Lighting Power.
USE C ATEG O R Y - V ER MO NT ED ITI O N CO M MO N SPACE T Y PE S
WH O LE BUILD ING WAT T S / SF
SPACE BY SPACE WAT T S / SF
0.72 0.54 0.18 1.26 1.10 0.45 1.10 1.08 0.20 1.10 0.80 0.54
Thrivent Financial Bank.
Photo courtesy Energy Center of Wisconsin
Active Storage Atrium – First Three Floors Atrium – Each Additional Floor Classroom/lecture/training Conference/Meeting/Multipurpose Corridor/Transition Electrical/Mechanical Food Preparation Inactive Storage Lobby Restroom Stairway
CO NVENTION CENTER
Exhibit Space Audience/Seating Area
1.08 1.17 0.63 1.08 0.81 1.71 0.81 1.17 0.54 1.17
CO UR TH O USE
Audience/Seating Area Courtroom Con fi nement Cells Judges Chambers Dressing/Locker/Fitting Room
DINING : BAR LO UNGE / LEISURE
58
1.26 Lounge/Leisure Dining Note: The lighting power densities contained in this table include allowances for video-display terminals, decorative lighting and display lighting Additional lighting power is not allowed for these uses. Task lighting is not included in these connected LPD limits. To view lighting power density requirements for other states, visit the Core Performance reference materials at www.advancedbuildings.net/refmaterials.htm. Password information can be found on the inside front cover of this book.
TABLE 2. 8.1 - INTERIOR LIGHTING P OWER ( CONTINUED )
WH O LE BUILD ING WAT T S / SF
1.26 1.44 1.40 1.08 0.90 0.99 0.45 1.26 0.90 0.54 0.30 0.81 0.81 0.80 0.72 0.27 0.99 0.54 0.36 1.26 0.81 0.90 0.90 1.35 2.43 0.72 1.26 0.54 0.90 0.81 0.63 1.08 0.36 1.98 0.72 0.81 0.54 1.08
USE C ATEG O R Y - V ER MO NT ED ITI O N DINING : C AFE TERIA / FA S T FO O D DINING : FA MILY
Dining Kitchen
SPACE BY SPACE WAT T S / SF
D O R MITO RY
Living Quarters Bedroom Study Hall
E X ERCISE CENTER
Dressing/Locker/Fitting Room Audience/Seating Area Exercise Area Exercise Area/Gymnasium
FIR E S TATI O N S
Fire Station Engine Room Sleeping Quarters
G YMNA SIUM
Dressing/Locker/Fitting Room Audience/Seating Area Playing Area Exercise Area
HE ALTHC ARE CLINIC
Corridors w/patient waiting, exam Exam/Treatment Emergency Public & Staff Lounge Hospital/Medical supplies Hospital - Nursery Nurse station Physical therapy Patient Room Pharmacy Hospital/Radiology Operating Room Recovery Active storage Laundry-Washing
HOSPITAL
Note: The lighting power densities contained in this table include allowances for video-display terminals, decorative lighting and display lighting Additional lighting power is not allowed for these uses. Task lighting is not included in these connected LPD limits. To view lighting power density requirements for other states, visit the Core Performance reference materials at www.advancedbuildings.net/refmaterials.htm. Password information can be found on the inside front cover of this book.
CORE PERFORMANCE REQUIREMENTS ○ 2.8. LIGHTING POWER DENSITY
59
TABLE 2. 8.1 - INTERIOR LIGHTING P OWER ( CONTINUED )
WH O LE BUILD ING WAT T S / SF
0.90 1.17 0.99 2.25 0.99 1.17 0.63 1.53 0.99 1.08 1.17 1.08 0.45 1.08 1.53 1.89 0.90 1.08 0.99 1.89 1.08 1.08 0.99 0.99 0.72 0.90 1.53 0.90 0.99 0.99 0.27 0.18 0.90 0.63 1.17 1.17 0.81 1.44 2.34 2.97 0.99
USE C ATEG O R Y - V ER MO NT ED ITI O N HOTEL
Dining Area Guest quarters Reception/Waiting Lobby
SPACE BY SPACE WAT T S / SF
LIBR AR Y
Library-Audio Visual Stacks Card File & Cataloguing Reading Area
M ANUFAC TURING
Equipment Room Corridor/Transition General Low Bay General High Bay Detailed
MOTEL
Dining Area Living quarters Reception/Waiting
MOTION PIC TURE THE ATER
Audience/Seating Area Lobby
MUSEUM
Active Storage General exhibition Restoration
O FFICE
Enclosed Open Plan
PARK ING G AR AG E
Garage Area
PENITENTIAR Y
Audience/Seating Area Classroom/Lecture/Training Dining Area Con fi nement Cells
PERFOR MING AR T S THE ATER
Audience/Seating Area Lobby Dressing/Locker/Fitting Room
Note: The lighting power densities contained in this table include allowances for video-display terminals, decorative lighting and display lighting Additional lighting power is not allowed for these uses. Task lighting is not included in these connected LPD limits. To view lighting power density requirements for other states, visit the Core Performance reference materials at www.advancedbuildings.net/refmaterials.htm. Password information can be found on the inside front cover of this book.
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CORE PERFORMANCE REQUIREMENTS ○ 2.8. LIGHTING POWER DENSITY
TABLE 2. 8.1 - INTERIOR LIGHTING P OWER ( CONTINUED )
WH O LE BUILD ING WAT T S / SF
0.90 1.26 0.99 1.08 1.00 1.17 0.60 2.16 1.30 1.30 1.62 2.61 1.30 1.30 1.30 1.53 1.44 1.30 1.08 1.26 0.70 0.99 0.99 0.45 0.50 1.10 0.99 0.36 2.43 2.07 0.99 0.90 1.89 0.90 0.54 1.35 0.45 0.60 1.26 0.60 1.26 1.90
USE C ATEG O R Y - V ER MO NT ED ITI O N P O LICE S TATI O NS
Police Station Laboratory
SPACE BY SPACE WAT T S / SF
P O S T O FFI C E
Sorting Area Lobby
RELIGIOUS BUILDINGS
Lobby Worship/Pulpit/Choir
RE TAIL
Department Store Sales Area Specialty Store Sales Area Fine Merchandise Sales Area Supermarket Sales Area Personal Services Sales Area Mass Merchandising Sales Area Mall Concourse
RE TAIL : SPECIALT Y RE TAIL : SUPER M ARKE T S CH O O L / UNI V ER SIT Y
Classroom Audience Dining Office Corridor Storage Laboratory
SP OR T S ARENA
Audience/Seating Area Ring Sports Area Court Sports Area
TOWN HALL TR ANSP OR TATION
Dining Area Baggage Area Airport - Concourse Terminal - Ticket Counter Reception/Waiting
LEED Relationship SS WE EA MR EQ credit 1
WAREH O USE
Fine Material Medium/Bulky Material
WO RK SH O P
Note: The lighting power densities contained in this table include allowances for video-display terminals, decorative lighting and display lighting Additional lighting power is not allowed for these uses. Task lighting is not included in these connected LPD limits. To view lighting power density requirements for other states, visit the Core Performance reference materials at www.advancedbuildings.net/refmaterials.htm. Password information can be found on the inside front cover of this book.
CORE PERFORMANCE REQUIREMENTS ○ 2.8. LIGHTING POWER DENSITY
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Introduction Design Process Requirements Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.9 Mechanical Equipment Efficiency Requirements
PURP OSE Reduce environmental impacts and operational costs associated with energy consumption of heating, ventilating and air conditioning equipment. CRITERIA Mechanical equipment shall comply with the following:
Package unitary equipment shall meet the minimum efficiency requirements in Tables 2.9.1 and 2.9.2 or be ENERGY STAR labeled. Gas Unit Heaters shall include an intermittent ignition device and have either power venting or a flue damper. Gas Furnaces <225,000 Btu/hr should have an AFUE rating of 90 or higher. Package Terminal Air Conditioners and Heat Pumps shall meet the minimum efficiency requirements in Table 2.9.3. Boilers shall meet the minimum efficiency requirements in Table 2.9.4. Electric chillers shall meet the energy efficiency requirements in Table 2.9.5. Absorption chillers shall meet the minimum efficiency requirements in Table 2.9.6. Equipment not listed shall meet ENERGY STAR Criteria where applicable. The most important aspect of HVAC performance is the overall efficiency of the whole system for delivery of space conditioning, not just the efficiencies for components given in the tables below. Using the design principles discussed in Criteria 1.4 Mechanical System Design will help assure that the balance of system components (pipes, ducts, pumps, fans, etc.) enhance the total system efficiency and that the system is sized for more efficient performance.
High levels of HVAC performance depend not only on selecting high efficiency components, but also upon proper sizing and system matching to loads.
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MECHANIC AL S YS TEM CRITERIA SPECIFIC ATIONS : TABLE 2.9.1 - UNITARY AIR CONDITIONERS AND CONDENSING UNITS, ELECTRICALLY OPERATED (Voluntary guidelines for use in energ y efficiency programs. For Terms and Usage, please see the CEE website at www.cee1.org.)
EQUIPMENT T Y PE SIZ E C ATEG O RY
< 65,000 Btu/h
SUB - C ATEG O RY OR R ATING CO NDITION
Split System Single Package
REQUIRED EFFICIENC Y
14.0 SEER 12.0 EER 14.0 SEER 11.6 EER 11.5 EER 11.9 IPLV 11.5 EER 11.9 IPLV 10.5 EER 10.9 IPLV 14.0 EER
AIR CO NDITIONER S, AIR CO O LED
≥ 65,000 Btu/h and < 135,000 Btu/h ≥ 135,000 Btu/h and < 240,000 Btu/h ≥ 240,000 Btu/h
Split System and Single Package Split System and Single Package Split System and Single Package Split System and Single Package
AIR CO NDITIONER S, WATER AND E VAP O R ATI V ELY CO O LED
All Sizes
Source: Consortium for Energ y Ef ficiency, CEE’s high-efficiency specifications are periodically revised. For the most current version, please see the CEE website at www.cee1.org/com/hecac/hecac-main.php3
CORE PERFORMANCE REQUIREMENTS ○ 2.9. MECHANICAL EQUIPMENT EFFICIENCY REQUIREMENTS
63
TABLE 2.9. 2 - UNITARY AND APPLIED HE AT PUMP S, ELEC TRIC ALLY OPER ATED (Voluntary guidelines for use in energ y efficiency programs. For Terms and Usage, please see the CEE website at www.cee1.org.)
EQUIPMENT T Y PE AIR CO O LED, ( CO O LING MO D E ) SIZ E C ATEG O RY
< 65,000 Btu/h
SUB - C ATEGORY OR R ATING CO ND ITI O N
Split System Single Package
REQUIRED EFFICIENC Y
14.0 SEER 12.0 EER 14.0 SEER 11.5 EER 11.9 IPLV 11.5 EER 11.9 IPLV 10.5 EER 10.9 IPLV 8.5 HSPF 8.0 HSPF 3.4 COP 2.4 COP 3.2 COP 2.1 COP 14.0 EER 4.6 COP
≥ 65,000 Btu/h and < 135,000 Btu/h ≥ 135,000 Btu/h and <240,000 Btu/h ≥240,000 Btu/h
Split System and Single Package Split System and Single Package Split System and Single Package Split System Single Package 47oF db/43oF wb Outdoor Air 17oF db/15oF wb Outdoor Air 47oF db/43oF wb Outdoor Air 17oF db/15oF wb Outdoor Air 85oF Entering Water 70 oF Entering Water
AIR CO O LED ( HE ATING MODE )
< 65,000 Btu/h (Cooling Capacity) ≥ 65,000 Btu/h and < 135,000 Btu/h (Cooling Capacity) ≥ 135,000 Btu/h (Cooling Capacity)
WATER S O URC E ( CO O LING MO D E ) WATER-S O URC E ( HE ATING MO D E )
< 135,000 Btu/h (Cooling Capacity) < 135,000 Btu/h (Cooling Capacity)
Source: Consortium for Energ y Ef ficiency, CEE’s high-efficiency specifications are periodically revised. For the most current version, please see the CEE website at www.cee1.org/com/hecac/hecac-main.php3 TABLE 2.9. 3 – PACK AGE TER MINAL AIR CONDITIONER S AND HE AT PUMP S, ELEC TRIC ALLY OPER ATED
EQUIPMENT T Y PE AIR CO NDITIONER S & HE AT PUMPS ( CO O LING MO D E ) SIZE C ATEGORY
< 7,000 Btu/h ≥ 7,000 Btu/h and < 10,000 Btu/h ≥ 10,000 Btu/h and <13,000 Btu/h ≥13,000 Btu/h
REQUIRED EFFICIENC Y
11.9 EER 11.3 EER 10.7 EER 9.5 EER
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CORE PERFORMANCE REQUIREMENTS ○ 2.9. MECHANICAL EQUIPMENT EFFICIENCY REQUIREMENTS
TABLE 2.9.4 – BOILER S & WARM AIR FURNACES
EQUIPMENT T Y PE BOILER S, G A S H OT WATER BOILER S, OIL WAR M AIR FURNACE S, G A S FIRED WAR M AIR , O IL FIRED WAR M AIR DUC T FURNACE , G A S FIRED WAR M AIR UNIT HE ATER , G A S FIRED WAR M AIR UNIT HE ATER , O IL FIRED SIZE C ATEGORY
< 300,000 Btu/h ≥ 300,000 Btu/h and < 2.5 mBtu/h < 300,000 Btu/h ≥ 300,000 Btu/h and < 2.5 mBtu/h <225,000 Btuh ≥225,000 Btuh <225,000 Btuh ≥225,000 Btuh
TE S T PRO CEDURE
DOE 10 CFR Part 430 DOE 10 CFR Part 431 DOE 10 CFR Part 430 DOE 10 CFR Part 431 DOE 10 CFR Part 430 ANSI Z21.47 DOE 10 CFR Part 430 UL 727
REQUIRED EFFICIENC Y
90% AFUE 89% Et 85% AFUE 85% Et 90% AFUE 90% Et 83% AFUE 83% Et
all sizes
ANSI Z83.9
80% Ec
all sizes
ANSI Z83.8
81% Ec
all sizes
UL 731
80% Ec
Et = thermal ef f icienc y Ec = combustion ef f icienc y * Systems must be designed with lower operating hot water temperatures where feasible (< 150 ◦F) and use hot water reset to take advantage of the much higher efficiencies of boilers.
CORE PERFORMANCE REQUIREMENTS ○ 2.9. MECHANICAL EQUIPMENT EFFICIENCY REQUIREMENTS
65
TABLE 2.9. 5 – CHILLER S
EQUIPMENT T Y PE SIZ E C ATEG O R Y REQUIRED EFFICIENC YCHILLER S WITH A SD O R WITHOUT A SD FULL LOAD ( K W / TO N ) AIR CO O LED W / CO ND ENSER AIR CO O LED W / O CO ND ENSER WATER CO O LED, RECIPRO C ATING WATER CO O LED, ROTARY S CREW AND S CRO LL
All All All < 90 tons ≥ 90 tons and < 150 tons ≥ 150 tons and ≤ 300 tons > 300 tons < 150 tons ≥ 150 tons and ≤ 300 tons > 300 tons and ≤ 600 tons > 600 tons a. b. c. 1.2 1.08 0.840 0.780 0.730 0.610 0.600 0.610 0.590 0.570 0.550
REQUIRED EFFICIENC YCHILLER S WITH A SD OP TIONAL CO MPLIANCE PATH FULL LOAD ( K W / TO N )
N/A N/A N/A N/A N/A N/A N/A 0.630 0.600 0.580 0.550
IPLV ( K W / TO N )
1.0 1.08 0.630 0.600 0.550 0.510 0.490 0.620 0.560 0.510 0.510
IPLV ( K W / TO N )
N/A N/A N/A N/A N/A N/A N/A 0.400 0.400 0.400 0.400
WATER CO O LED, CENTRIFUG AL
Compliance with full load efficiency numbers and IPLV numbers are both required. Systems with single chillers that operate on 460/480V require VSDs. VSDs are optional in multiple chiller systems. Water-cooled centrifugal water-chilling packages that are not designed for operation at ARI Standard 550/590 test conditions (and thus cannot be tested to meet the requirements of Table 2.5.5) of 44* F leaving chilled water temperature and 85* F entering condenser water temperature shall meet the applicable full load and IPLV/NPLV requirements in Appendix B., Tables 1-6.
TABLE 2.9.6 – ABS ORP TION CHILLER S
EQUIPMENT T Y PE REQUIRED EFFICIENC Y FULL LOAD CO P ( IPLV )
0.60, but only allowed in heat recovery applications 0.70, but only allowed in heat recovery applications 1.0(1.05) 1.20
LEED Relationship SS WE EA MR EQ credit 1
AIR CO O LED, SING LE EFFEC T WATER CO O LED, SING LE EFFEC T D O UBLE EFFEC T – DIREC T FIRED D O UBLE EFFEC T – INDIREC T FIRED
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CORE PERFORMANCE REQUIREMENTS ○ 2.9. MECHANICAL EQUIPMENT EFFICIENCY REQUIREMENTS
Introduction Design Process Strategies
2.10 Dedicated Mechanical Systems
PURP OSE To isolate process load-driven systems from systems serving zones requiring only comfort conditioning. CRITERIA Zones with special process temperature requirements and/or humidity requirements should be served by separate air distribution systems from those serving zones requiring only comfort conditioning or shall include separate supplementary control provisions so that the primary systems may be specifically controlled for comfort purposes only. When the project includes special areas with significantly different load profi les than the main building (i.e. server rooms, equipment rooms, etc.), these areas should be served by a separate, dedicated system designed for that specific area and load. Meeting these loads should not require operation of the main building systems. Exception: Zones requiring only comfort conditioning may be served by a process load system provided that the total supply air to those zones is no more than 25% of total process load system supply air and the total conditioned area of the comfort zones is less than 1,000 square feet.
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.11 Demand Control Ventilation
PURP OSE Reduce the energy use associated with heating and cooling outside air in excess of ventilation flow rates required by building occupancy, while maintaining high indoor air quality for the building occupants. CRITERIA Install a demand control ventilation (DCV) system on any single zone HVAC system to monitor Carbon Dioxide (CO2 ) concentration in the occupied spaces in the building, and reduce or increase outside air flow rates according to occupant density and indoor air quality as determined by the CO2 sensors. Economizer control should be configured so that when cooling by economizer is called for, air damper control responds to economizer settings, rather than CO2 sensors. CO2 setpoint should be set to begin increasing ventilation at a CO2 concentration of 800 ppm, and allow a maximum CO2 concentration of 950 ppm in the space. If a differential setpoint with outside conditions is established, the setpoint should maintain a CO2 differential between inside and outside of no greater than 530 ppm. (Typical outside air CO2 concentration is 430ppm.)
Sensor data from 7 temporary sensors installed as a demonstration during conference.
68
Demand control ventilation, using CO2 levels as the indicator, is an excellent way to control ventilation in areas with fluctuating occupancy, such as g yms, auditoriums, and exhibit halls. This diagnostic graph shows clearly that the existing standard controls, which responded only to temperature, seriously underestimated the ventilation air requirement for the space during the reception on 11/12/02 beginning at 5PM. Manual operation was required to overcome the lack of CO2 control to bring the space into recommended range.
In space types with specific contaminants (such as retail applications with VOC from retail stock), occupant density is not an appropriate basis for control of ventilation rate. CO2 controls are particularly useful in areas where occupancy is highly variable and irregular, such as meeting rooms, studios, theaters, educational facilities, etc. CO2 control should allow for both a reduction of outside air flow when occupancy is low, and an increase in outside air flow beyond minimum setpoints when occupancy is high. ASHRAE Standard 62 recognizes ventilation rates based on indoor air quality monitoring as meeting the intent of that standard to maintain indoor air quality and minimum ventilation for occupants.
LEED Relationship SS WE EA MR EQ credit 1
CORE PERFORMANCE REQUIREMENTS ○ 2.11 DEMAND CONTROL VENTILATION
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
2.12 Domestic Hot Water System Efficiency
PURP OSE Reduce standby losses and inefficiency associated with maintaining a constant supply of hot water for domestic uses. CRITERIA Domestic hot water loads should be served by gas or electric demand hot water heating systems (also referred to as tankless water heaters), high efficiency tank water heaters, or sealed combustion hot water heating systems. In Vermont, the Vermont Commercial Energy Code limits electric water heating to a maximum of 5 kW total power input. High efficiency tank water heating systems should include R-14 tank insulation, and heat traps to prevent thermosiphoning. For fossil-fuel fired systems that are not sealed combustion, include flue control dampers. To limit hot water consumption, install water conserving aerators and shower heads in lavatories and staff areas.
This condensing gas water heater is 94% efficient.
LEED Relationship SS WE EA MR EQ credit 1
70
Introduction Design Process Strategies
2.13 Fundamental Economizer Performance
PURP OSE Ensure optimal energy savings from the proper performance of outside air (OA) economizers. CRITERIA Economizers should incorporate the following features and verify performance at project completion:
Fa c t o r y - i n s t a l l e d e c o n o m i z e r.
Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Factory-installed economizers are generally more reliable than field installed economizers. There are conditions that call for field installation of economizers. Fu l l y - m o d u l a t i n g d a m p e r m o t o r. A fully-modulating damper motor is necessary to allow proper mixed air temperature control and to allow the economizer to maximize operating hours. D a m p e r d r i ve m e c h a n i s m . Robust economizer operation requires a direct modulating actuator with gear driven interconnections and a permanently lubricated bushing or bearing on the outside and return dampers. P r o p o r t i o n a l d a m p e r c o n t r o l . Locate an analog sensor upstream of the cooling coil in a location where the return and outside air streams have been adequately mixed to control the economizer’s modulating dampers. C o o r d i n a t e d c o n t r o l . Ensure the economizer is only active when there is a call for cooling. Economizer controller will utilize a deadband between economizer enable/disable operation of no greater than 2°F in a dry-bulb temperature application and 2 Btu/lb in an enthalpy application. Ec o n o m i z e r c o n t r o l Economizer control type will be differential drybulb, differential enthalpy or dewpoint/dry-bulb temperature control. In Vermont, the control type must be differential enthalpy. Outside of Vermont, dewpoint/dry-bulb control is now an allowable option in ASHRAE 90.1. Speci fic climatic conditions should help determine the most appropriate type of control/sensor strategy. Re l i e f a i r a n d m o d u l a t i n g r e t u r n a i r d a m p e r. Provide relief air with either a barometric damper in the return air duct upstream of the return air damper, a motorized exhaust air damper or an exhaust fan. M i n i m u m o u t s i d e ve n t i l a t i o n a i r m e a s u r e m e n t by t e m p e r a t u r e. Verify the minimum OA setpoint by measuring the temperature of the mixed air, return air and outside air to calculate the percentage of outside air. This measurement is conducted during acceptance testing, and may also be an on-going operational control point.
71
GENER AL When there are cooling loads at the same time that outside air is sufficiently cool, an outside air economizer allows space conditioning using outside air, rather than mechanical cooling. In some climates, economizer use reduces the amount of energy used for mechanical cooling by 20 to 60%. There are a number of design conditions that, in combination, determine economizer performance: the economizer must coordinate or interlock with mechanical cooling so that it is only used when there is a call for cooling; a changeover control must return outside air dampers to the minimum ventilation position when outside air is too warm to provide cooling; and the level of economizer control integration determines the ability to make full use of outside air before mechanical cooling is used.
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CORE PERFORMANCE REQUIREMENTS ○ 2.13 FUNDAMENTAL ECONOMIZER PERFORMANCE
Section Three: Enhanced Performance Strategies
3.1 Cool Roofs 3.2 Daylighting and Controls 3.3 Additional Lighting Power Reductions 3.4 Plug Loads/Appliance Efficiency 3.5 Supply Air Temperature Reset (VAV) 3.6 Indirect Evaporative Cooling 3.7 Energy Recovery 3.8 Night Venting 3.9 Premium Economizer Performance
Enhanced Performance Strategies
3.10 Variable Speed Control 3.11 Demand-Responsive Buildings (Peak Power Reduction) 3.12 On-Site Supply of Renewable Energy 3.13 Additional Commissioning Strategies 3.14 Fault Detection and Diagnostics
The Criteria in this section are not part of the basic requirements of the Core Performance program. However, the strategies identified here represent opportunities for significant additional energy savings. Individual Criteria should be considered in the context of project characteristics and climate conditions.
Introduction Design Process Strategies Core Performance Requirements
3.1 Cool Roofs
PURP OSE Promote the installation of roof surfaces that reduce urban heat island effect, reduce energy use and provide other environmental benefits. CRITERIA On low-slope roofs (2:12 or less), install an ENERGY STAR-labeled Cool Roof with an emmissivity of at least 0.9 for a minimum of 75% of the roof surface, or install an ecoroof for a minimum of 50% of the roof surface. The radiative property values should be rated by a laboratory accredited by the Cool Roof Rating Council. ENERGY STAR Criteria are as follows: Low slope roofs must have an initial solar reflectance of >0.65. After three years, the solar reflectance must be >0.50. Steep slope roofs must have an initial solar reflectance of >0.25. After three years, the solar reflectance must be >0.15.
Enhanced Performance Strategies Energy Modeling Appendices
Cool roofs not only have a positive effect by reducing the building loads, they also reduce the “heat island” impact of the building on its surroundings.
LEED Relationship SS WE EA MR EQ credit 7.2
75
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
3.2 Daylighting and Controls
PURP OSE Incorporate daylighting systems to reduce lighting energy use and improve indoor lighting quality. CRITERIA
LEED Relationship SS WE EA MR EQ credit 8.1 credit 1
Install skylights over occupied spaces to bring in diffuse daylight. Skylights should serve all open areas, and enclosed spaces larger than 1000 sf. Skylight area should not exceed 3-5% of the floor area. Install daylight controls to control lighting in all toplit daylight zones. Toplit daylighting zones are generally considered to be the area within 0.75 times the ceiling height distance beyond the edge of the skylight well. Coordinate zones and controls with the daylight control requirements of Criteria 2.7 Lighting Controls. Install daylight controls in all side daylit zones. For perimeter spaces with vertical glazing, daylit zones are generally considered to include spaces within 1.5 times the ceiling height of the exterior wall, or within 2 times the window head height. Coordinate zones and controls with the daylight control requirements of Criteria 2.7 Lighting Controls. Daylight controls should be able to reduce lighting levels by at least 50% in response to daylight. Continuous dimming is recommended for occupied spaces with ceiling heights of 14 ft or lower. Glazing intended to serve as daylight glazing should not increase total building glazed area above 40% window wall ratio, as indicated in Criteria 2.6 Fenestration. Daylight glazing must be designed to limit direct sunlight introduced to the occupied space through the daylight glazing. Overhead glazing should be designed to prevent direct sun from entering the occupied space. Vertical glazing above 7’0” aff must have fixed shading devices, or operable shading devices controlled separately from the view glazing, to control direct sun. As a guideline, south glazing systems should be designed to limit direct sun at solar noon for the days between spring and fall equinox. East and West daylight glazing should be minimized, and designed to eliminate direct sun after 10 am and before 2 pm between spring and fall equinox. All daylight controls should be calibrated and tested at the time of installation as recommended by the manufacturer’s start-up Criteria to verify that the systems are working properly. (see Criteria 1.5)
It is recommended that the performance of the architectural daylight system be evaluated with a daylight model. For additional information on designing effective daylight and control systems, see www.advancedbuildings.net.
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3.3 Additional Lighting Power Reductions
PURP OSE To reduce connected lighting load to achieve the requirements of the Energy Policy Act of 2005 and qualify for Federal tax incentives. CRITERIA Reduce connected lighting load by at least 40% below the allowances of the ASHRAE 90.1 reference standard used by EPAct 05, while meeting all of the lighting control requirements of that standard. (Note that EPAct05 uses the 2001 version of the ASHRAE 90.1 standard as a reference point, even though newer versions of 90.1 are in force.) GENER AL Projects which meet the lighting power density (LPD) and control requirements of Core Performance are well on their way to qualifying for federal tax incentives under the Energy Policy act of 2005 (EPAct 05). An additional effort on the part of the design team to reduce connected lighting load can result in eligibility of the project to receive tax incentives. For tax-exempt public projects, the tax incentive can be transferred directly to the design team. The basic requirements of EPAct 05 are to reduce LPD by 25% to 40% below the requirements of ASHRAE 90.1-2001, and to implement the interior and exterior lighting control requirements of that standard. Achieving this qualifies the project for a Federal tax deduction of $0.30 to $0.60 per square foot of building area under the current policy. (Increases in the incentive level and program extensions are currently under consideration; current program requirements should be verified.) The goal of this Criteria is to achieve a 40% reduction in connected lighting load (compared to the EPAct 05 baseline) which represents approximately a 20% reduction below the requirements listed in Criteria 2.8. Specific targets are shown in the LPD table below, which is derived from typical LPD requirements of ASHRAE 90.1-2001 as listed in Table 9.3.1.1 of that standard. Note that the values in this table represent only a subset of building space types and are provided for reference only. TABLE 3. 3.1 - APPROX IM ATE LPD REQUIREMENT S FOR ACHIE VING EPAC T05
BUILDING ARE A T Y PE CO NV ENTION CENTER DINING E X ERCISE CENTER G YMNA SIUM HOSPITAL / HE ALTH C ARE LIBR ARY O FFIC E PERFOR MING AR T S THE ATER P O LIC E / FIRE S TATI O N RELIGIOUS BUILDING RE TAIL S C H O O L / UNI V ER SIT Y TOWN HALL WAREH O USE 4 0 % LIGHTING P OWER DENSIT Y REDUC TION TARGE T
0.85 0.9-1.15 0.85 1.0 0.95 0.9 0.78 0.9 0.78 1.32 1.15 0.9 0.85 0.72
Enhanced Performance Strategies Energy Modeling Appendices
National Wildlife Federation Headquarters, Reston, Virginia
Courtesy of Hedrich-Blessing
LEED Relationship SS WE EA MR EQ credit 1
(For additional space types, see ASHR AE 90.1-2001 Table 9.3.1.1)
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
3.4 Plug Loads/Appliance Efficiency
PURP OSE Reduce energy use associated with equipment installed or located in the building. CRITERIA Identify equipment selection and control strategies to reduce the energy use of equipment installed or used in the building. Purchase and install only equipment rated by the ENERGY STAR program where applicable. Institute office equipment control strategies to reduce equipment run-time. For all equipment types rated by ENERGY STAR, utilize only ENERGY STAR-qualified equipment. (Specific equipment types identified below must comply with requirements listed.) For equipment types not rated by ENERGY STAR, compare energy use characteristics of alternative selections and target the acquisition of lower-consumption equipment. Install networked computer monitor control, or insure that at least 90% of computer monitors are flat-screen LCD-type monitors with low-energy-use characteristics. Enable power management settings on all computer workstations, and consider third-party centralized power management strategies to reduce equipment energy use. EPA’s ENERGY STAR program has developed performance Criteria for a wide range of equipment and appliances, from office equipment to residential appliances to commercial kitchen equipment. All equipment purchased for use in an Advanced Building should meet the performance Criteria established by ENERGY STAR. The tables below provide specific equipment performance requirements for commercial refrigeration and ice-making equipment that goes beyond basic ENERGY STAR performance requirements and should be targeted for this type of equipment. TABLE 3.4.1 - CRITERIA SPECIFIC ATIONS FOR TIER 2 REFRIGER ATION EQUIPMENT PERFOR M ANCE
EQUIPMENT S O LID D O O R RE ACH - IN REFRIGER ATOR S O LID D O O R RE AC H - IN FREE Z ER TIER CO RRESP ONDING BA SE SPECIFIC ATION
ENERGY STAR + 40%
M A X IMUM DAILY ENERG Y USE / DAY ( K WH / DAY )
.06V + 1.22
2
2
ENERGY STAR + 30%
0.28V + 0.97
V = INTERNAL VO LUME, CUBIC FEE T | A SHR AE STANDARD 117-20 02 / 38 DEG . F
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TABLE 3.4. 2 - CRITERIA SPECIFIC ATIONS FOR TIER 2 ICEM AKING EQUIPMENT PERFOR M ANCE
HARVEST R ATE (10 0 LBS ICE / 24 HR S )
<500 lbs day
EQUIPMENT T Y PE
TIER
CO R R E SP O ND ING BA SE SPECIFIC ATION
M A X IMUM DAILY ENERG Y CO NSUMP TI O N ( K WH PER 10 0 LBS. ICE )
6.24 - .0044H
M A X IMUM DAILY WATER USE ( G ALLO NS PER 10 0 LBS. ICE )
200 - .022H
ICE- M AKING HE AD WATER CO O LED ICE- M AKING HE AD AIR CO O LED REMOTECO ND ENSING AIR CO O LED SELF CO NTAINED WATER CO O LED SELF CO NTAINED AIR CO O LED
2
20% below FEMP
> 500 lbs day
2
20% below FEMP
4.46 - .0009H
200 - .022H
<450 lbs day
2
20% below FEMP
8.21 - .0069H
Not Applicable
> 450 lbs day
2
20% below FEMP
5.51 - .0009H
Not Applicable
<1000 lbs day
2
20% below FEMP
7.08 - .0030 H
Not Applicable
> 1000 lbs day
2
20% below FEMP
4.08
Not Applicable
<200 lbs day
2
20% below FEMP
9.12 - .0152H
191 - .0315H
> 200 lbs day
2
20% below FEMP
6.08
191 - .0315H
<175 lbs day > 175 lbs day
2 N/A
20% below FEMP Not Applicable
14.4 – 0.375H Not Applicable
Not Applicable Not Applicable
H = I C E H A R V E S T R AT E ( L B S / 24 H R S ) , A S H R A E S TA N DA R D 2 9 -19 8 8 ( R 9 9 ) Federal Energy Management Program (FEMP); www.eren.doe.gov/femp/procurement/ice_makers.html
LEED Relationship SS WE EA MR EQ credit 1
ENHANCED PERFORMANCE STRATEGIES ○ 3.4 PLUG LOADS/APPLIANCE EFFICIENCY
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3.5 Supply Air Temperature Reset (VAV)
PURP OSE To reduce the energy use associated with cooling systems in VAV configurations when zones may require reheating of central supply air for temperature maintenance. CRITERIA Employ a control strategy that resets cooling supply air temperature in shoulder and cool weather seasons. During reset mode, employ a demand-based control that uses the warmest central supply air temperature setting that will satisfy all zones in cooling, to reduce the need for reheat. GENER AL The standard cooling supply air temperature setpoint (e.g. 55°F) is often only needed at design cooling conditions, i.e., summer months. In cooler seasons, the low cooling supply air temperature setpoint can lead to increased energy use by requiring both additional cooling and zone reheat in VAV systems, especially at the building perimeter. By resetting the supply air temperature setpoint higher during these conditions, the need for cooling and reheating energy use can be reduced. A typical strategy is to reset the temperature of the cooling supply air to the warmest setting that still meets the cooling load of the warmest zone at any given time. This temperature setpoint may float through the range of 55 to 65°F in cooler seasons while still meeting cooling demand in the building. This strategy, supply air temperature reset or SATR, will also maximize the potential for economizer free cooling by expanding its range, especially helpful for displacement ventilation systems with their higher cooling supply air temperatures. Moist outdoor conditions will affect the feasibility of supply air temperature setbacks. In moist climates, humidity monitoring should be used in conjunction with feedback from terminal boxes to determine whether reset is possible. In the warmest months, the advantages of supply air temperature reset are lost, and a single setpoint is most effective.
LEED Relationship SS WE EA MR EQ credit 1
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Introduction Design Process Strategies Core Performance Requirements
3.6 Indirect Evaporative Cooling
PURP OSE Offset conventional cooling load by implementing energy efficient indirect evaporative cooling. CRITERIA Incorporate indirect evaporative cooling equipment to pre-cool outside air supplied to the building upstream of the conventional cooling equipment. Several configurations are available depending on equipment size and climate conditions; all provide energy savings over conventional cooling strategies. GENER AL Evaporative cooling technologies can deliver all or part of building comfort cooling needs by converting sensible heat (hot, dry air) to latent heat (cooler, moist air) through the process of evaporating water at ambient temperatures. The conventional direct evaporative cooler adds moisture to the conditioned air, which may not be appropriate in all climate types. Indirect evaporative coolers do not add moisture to building supply air and are therefore appropriate in a much broader range of climates and conditions. Indirect evaporative cooling technology uses evaporation to cool a warm dry air stream below ambient temperatures. (Depending on equipment configuration, this air stream may be warm building exhaust, or outside air.) The cool, moist air stream passes through a heat exchanger to absorb heat (transfer cool) to the warm incoming outside air used to supply building cooling or ventilation systems. The moist air stream is exhausted before it is introduced to the building, but the incoming supply air is now pre-cooled before it reaches the conventional cooling coil, reducing the load on that equipment. Under many shoulder conditions, indirect evaporative cooling may meet all of the building cooling loads, completely offsetting conventional cooling needs and extending economizer function. Under other peak cooling conditions, the indirect evaporative module provides pre-cooling to reduce the load on the conventional cooling coil. Evaporative cooling in any form loses efficiency as outdoor humidity increases, so the effectiveness of the system is climate specific. Evaporative cooling reduces cooling energy use and is particularly effective in reducing peak demand in hot, dry climates. Peak demand is reduced because power demand for evaporative systems remains constant as outside temperatures rise and because the efficiency and capacity of these systems tends to increase at higher outside temperatures while standard compressor-based systems become less effective at high outside temperature.
Enhanced Performance Strategies Energy Modeling Appendices
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PRO D UC T CO NFIGUR ATI O NS INDIREC T- O NLY CO O LER S
Indirect evaporative products currently on the market are of two basic types: uses a standard plate-type heat exchanger and can reduce the dry-bulb temperature with a wet-bulb effectiveness of about 75%. While commercial scale indirect units can be used on their own, they are often found in larger specially engineered package systems. S e c o n d t y p e of indirect cooler uses a more complex heat exchanger, involving multiple indirect heat exchange steps. Currently available products using this technology fall in the residential to light commercial range. They use a staged, cross-flow channeling system to cool air incrementally.
Tr a d i t i o n a l t y p e
FIGURE 3.6.1
One of the huge advantages of evaporative cooling is that its efficiency increases with increased outdoor temperatures, while conventional compressor cooling becomes less efficient with increasing temperature. The chart has been simplified to save space. The compressor cooling is to scale but the evaporative cooling equivalent EER values are more than double what is shown here.
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ENHANCED PERFORMANCE STRATEGIES ○ 3.6 INDIRECT EVAPORATIVE COOLING
H Y BRID S YS TEM S
The hybrid category includes systems that combine indirect evaporative cooling with at least one other cooling technology.
I n d i r e c t / D i r e c t e v a p o r a t i ve.
This two-stage evaporative cooling uses an indirect cooler to pre-cool the incoming air, which then passes to a direct evaporative cooling stage. The direct stage adds water to the air, but the system can still fully achieve the comfort conditions in areas of low humidity. Most recent product development has been directed at the residential sector, which may also be applicable to some small commercial buildings
Many large-scale and engineered systems use a hybrid approach involving multiple components, often including both indirect and direct evaporative cooling as well as a conventional cooling module. The use of the three techniques together - exhaust air heat recovery, indirect evaporative cooling and direct evaporative cooling - may meet the full cooling load and provide 100% outside air, even without any of those individual components being exceptionally efficient. The smallest available scale for such systems is currently about 7.5 tons. I n d i r e c t / DX . A new, different hybrid approach, which is currently in the proofof-concept stage, uses an indirect evaporative cooler packaged with an efficient economizer plus a compressor cycle that can be used when necessary to get the last 10°F or so of cooling in the supply air. This unit holds the promise of a 30to 50% reduction in electrical demand.
M u l t i - s t a g e b u i l t- u p s y s t e m s .
LEED Relationship SS WE EA MR EQ credit 1
ENHANCED PERFORMANCE STRATEGIES ○ 3.6 INDIRECT EVAPORATIVE COOLING
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3.7 Energy Recovery
PURP OSE Reduce energy use associated with ventilation requirements by recapturing waste heat in exhaust air flow. CRITERIA Install an energy recovery ventilation (ERV) system that includes latent heat recovery with an effectiveness of 70% or higher (heat-wheel type) unless local or internal humidity control conditions preclude latent recovery. In that case, install an air-to-air sensible heat recovery system with an effectiveness of at least 60%. All units should be on the approved list of the Air Conditioning and Refrigeration Institute (ARI). GENER AL Although ASHRAE 90.1-2004 and the Vermont Commercial Energy Code require the installation of energy recovery systems under certain specific conditions, these systems can save significant energy in a range of additional conditions beyond those identified by these standards. The installation of energy or heat recovery ventilation systems should be considered when any of the following conditions are anticipated: The building will be operated for extended hours, increasing the number of hours with a higher temperature differential between interior and exterior conditions. Buildings in cold climates Buildings or systems with high outside air ventilation rates as percentage of total air flow Buildings with high occupant densities which drive increased ventilation rates
Some mechanical system components include heat recovery options at a lower cost than dedicated stand-alone systems. Heat recovery options should be considered opportunistically when available as equipment options in conjunction with other systems. The capacity of the HVAC system should be recalculated to account for the reduced loads from the heat recovery system. LEED Relationship SS WE EA MR EQ credit 1 To reduce fan energy penalties, heat recovery systems should include a coil-bypass to allow unrestricted airflow past the heat recovery coil when the building is in economizer mode or the heat recovery system is not operating.
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3.8 Night Venting
PURP OSE Use building’s intrinsic thermal mass to reduce peak cooling loads by circulating cool nighttime air to pre-cool the building prior to daily occupancy in the cooling season. CRITERIA Install a building control system capable of operating ventilation fans in economizer mode on a scheduled basis in the cooling season. Set the controls to operate the ventilation fans to bring in outside air at partial flows for several hours prior to building occupancy each morning to precool building mass and reduce peak cooling loads. This strategy requires the incorporation of internal mass elements in the building (i.e. exposed concrete or masonry interior elements). Night ventilation should be controlled to prevent an increase in morning warm-up energy needs in winter and shoulder seasons. Excessive or prolonged fan operation will offset cooling energy savings, so consider implementation of lowflow or shorter duration night ventilation strategies. Night humidity conditions may preclude the use of this strategy.
Enhanced Performance Strategies Energy Modeling Appendices
Building mass can be used in conjunction with a night ventilation strateg y to reduce peak cooling loads in the building spaces.
LEED Relationship SS WE EA MR EQ credit 1
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3.9 Premium Economizer Performance
PURP OSE Increase the savings associated with economizer systems by adding control and verification features to the economizer system. CRITERIA In addition to the Fundamental Economizer Requirements in Criteria 2.13, include the following in the design and implementation of the economizers:
D e d i c a t e d t h e r m o s t a t s t a g e f o r e c o n o m i z e r.
To obtain the greatest energy savings benefit, the economizer needs to provide cooling first, before the cooling compressor is engaged. Most economizer controllers have differential logic built in; the addition of a drybulb return air sensor (while maintaining an outside air sensor) increases savings.
D i f f e r e n t i a l c h a n g e ove r w i t h b o t h a r e t u r n a n d o u t s i d e a i r s e n s o r.
D r y- b u l b c h a n g e ove r i n d r i e r we s t e r n c l i m ate s a n d t h e u s e o f e n t h a l py
s e n s o r s i n m o r e h u m i d e a s t e r n r e g i o n s . In western climates, high humidity rarely occurs near changeover temperatures, and dry-bulb sensors provide higher expected reliability at lower cost. In the more humid eastern US, enthalpy sensors are appropriate.
Primary control sensor placement
should be in the discharge air position, after the cooling coil, for a direct-expansion (DX) cooling coil, and before the cooling coil in the mixed-air position, when chilled water coils are used. to stop the compressor from operating when the outside air is below setpoint. With this strategy, an economizer failure may result in a high temperature comfort complaint and service request, so the economizer is more likely to get needed service.
L o w a m b i e n t o u t s i d e a i r c o m p r e s s o r l o c ko u t ,
Installer training
that covers basic and advanced economizer operation and controls for the brand of economizer installed.
A d v a n c e d d o c u m e n t e d c h e c ko u t . M i n i m u m a i r f l o w.
The change in temperature across the cooling coil in full cooling, must be no more than 25°F and no less than 10°F, indicating that air flow is adequate.
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GENER AL
THER MOSTAT AND CO NTROL S IMPLIC ATIONS
The Premium Economizer Requirements require a programmable thermostat with two cooling stages. Even a simple two-stage thermostat will allow alternating integration, the best integration of compressor and economizer that can be obtained with a single-stage compressor. More sophisticated programmable thermostats include microprocessor control and support full economizer integration with rooftop units employing multi-stage compressors or VFDs, meaning the economizer can be used to satisfy partial cooling loads, even when the compressor is running. Some microprocessor-based thermostats are “smart” enough to provide proportional integrated control and to include some anticipatory logic built into the control algorithms.
LE V E L S O F ECO N O M I Z E R CO N T R O L INT EG R ATI O N
“Integration” refers to an economizer’s ability to provide “partial cooling even when additional mechanical cooling is required to meet the remainder of the cooling load” (ASHRAE 2004, 38). Five discrete levels of integration exist, including a “non-integrated” case. The first two levels use a single-stage cooling thermostat, while the final three require a dedicated thermostat stage for the economizer.
N o n - i n t e g r a t e d o r e xc l u s i ve o p e r a t i o n .
Below the changeover setting, only the economizer operates. Above the changeover setting, only mechanical cooling operates.
T i m e - d e l ay i n t e g r a t i o n .
On a call for cooling, the economizer operates for a set time (typically 5 minutes); then, if there is still a need for cooling, the cooling coil operates. The dampers return to minimum ventilation at the end of the call for cooling. This is the best integration that can be achieved with a single-stage direct-expansion cooling unit. The first cooling stage activates the economizer. When the second stage is activated, the cooling compressor operates and the economizer dampers reduce OSA to avoid comfort problems from discharge air that is too cold.
Alternating integration.
Partial integration.
Integration is improved with a multiple-stage or variablespeed compressor direct-expansion cooling unit, able to provide partial cooling. Partial mechanical cooling provides less temperature drop when the compressor is on, and the economizer can use a lower outside air temperature and do more outside air cooling than in alternating integration. A hydronic chilled-water cooling coil can be modulated to any cooling output, allowing the economizer to be fully open when additional cooling is required.
Fu l l i n t e g r a t i o n .
ENHANCED PERFORMANCE STRATEGIES ○ 3.9 PREMIUM ECONOMIZER PERFORMANCE
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3.10 Variable Speed Control
PURP OSE Promote energy efficiency through variable control of air and fluid flow. CRITERIA Individual pumps serving variable flow systems and VAV fans having a motor horsepower of 5 hp or larger shall have controls and/or devices (such as variable speed control) that will result in pump or fan motor demand of no more than 30% of design wattage at 50% of design flow. GENER AL Variable-speed drives vary the frequency of air conditioning electricity in response to an electrical signal. When coupled to a fan or pump motor, the change in frequency will result in a corresponding change in motor speed. Since the power required to drive centrifugal fans or pumps is proportional to the cube of the fan or pump speed, large reductions in electricity are achieved when fans or pumps operate at reduced speeds. Variable-speed drives are most commonly applied to supply and return fans for variable air volume systems, circulating pumps in hydronic systems and domestic water booster pumps in high-rise buildings. In many cases, the motors are controlled to maintain a constant pressure within air ducts or water pipes. A pressure sensor in the pipe or duct sends a signal to the building automation system that in turn sends an electronic signal to the drive. Thus, as valves and dampers close, the pressure rises, which in turn causes the flow to be reduced. The sensor should be located near the end of the distribution loop.
LEED Relationship SS WE EA MR EQ credit 1
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3.11 Demand-Responsive Buildings (Peak Power Reduction)
PURP OSE Create buildings that help manage utility grid demand by responding to critical peak periods (either building peak or system peak) with equipment and design strategies able to reduce electrical demand or with equipment able to replace electricity supply. CRITERIA The building shall have the ability to automatically reduce total electrical demand by at least 10% during critical peak power periods. The building shall include an interface to the utility capable of responding to real-time signals which identify critical peak power periods. The building shall respond to this signal by utilizing one or more of the following strategies:
Enhanced Performance Strategies Energy Modeling Appendices
Reduce mechanical equipment power demand. Reduce lighting equipment power demand without compromising necessary illumination in critical areas. Critical areas include spaces within the building that host tasks requiring a moderate to high degree of visual acuity (i.e. IESNA illuminance categories E or higher). Thermal energy storage.
On-site power generation using nonrenewable resources does not meet these requirements.
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3.12 On-Site Supply of Renewable Energy
PURP OSE Promote use of renewable energy in buildings. CRITERIA Incorporate an on-site renewable energy system to supply 5% or more of total building electrical loads. Note: Daylighting and passive solar systems are not considered part of this Criteria.
LEED Relationship SS WE EA MR EQ credit 2
A 60 kW grid-connected photovoltaic array on the roof of Oberlin College’s Adam Joseph Lewis Center for Environmental Studies generates a substantial portion of the annual electricity use of the facility.
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Introduction Design Process Strategies Core Performance Requirements
3.13 Additional Commissioning Strategies
PURP OSE Support the owner, design team, construction team and operations team in assuring the project’s design intent is properly implemented from design through operation. CRITERIA
Enhanced Performance Strategies Energy Modeling Appendices
A third-party commissioning agent (CxA), independent of the design and construction management team, provides commissioning services to the building owner. The CxA must maintain certification credentials from either the Building Commissioning Association or an equivalent organization. A CxA conducts a peer review of the design development, construction documents, specifications and bid submittals. The CxA reviews the documentation developed to describe design intent in Criteria 1.2 and certifies that the final design package meets the intent of these documents. The CxA develops a commissioning plan for implementation as described in Criteria 1.5. The CxA also participates in the operator training undertaken in Criteria 1.6.
The CxA shall attend regular meetings with the owner’s agent to review construction progress, pre-functional test requirements and witness acceptance test results. They shall verify test results and complete all documentation required by Criteria 1.5. The CxA is responsible for reviewing the final commissioning report with owner’s agent and verifying that Criteria 1.5 is completed.
Occupant comfort survey data can help identify building operating problems. Additional information about building occupant surveys can be found at the Advanced Buildings website.
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GENER AL Additional commissioning utilizes Criteria 1.2, 1.5 and 1.6 as a framework to deliver building commissioning services through an independent, certified third party. Contracting for commissioning process services through a separate, independent professional or utilizing owner’s employees enables the Commissioning Agent (CxA) to focus on the commissioning process and to avoid potential conflicts of interest. In certain cases, the CxA may be an employee, associate or partner of the architect, engineer or construction management firm, but should not be part of the design team or construction management team. Whenever this choice is selected by the owner, the CxA should be separated from the design element or construction management unit in order to provide the owner with the independence required for the Commissioning Process to be successful and to avoid any confl icts of interest.
LEED Relationship SS WE EA MR EQ credit 3
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Introduction Design Process Strategies Core Performance Requirements
3.14 Fault Detection and Diagnostics
PURP OSE Provide tools to verify and maintain on-going operational performance of roof top HVAC equipment by monitoring key performance parameters of this equipment. CRITERIA Incorporate fault detection and diagnostics (FDD) capabilities in all manufactured rooftop HVAC equipment to monitor equipment performance in the following categories:
Enhanced Performance Strategies Energy Modeling Appendices
REFRIG ER ANT CHARG E AIRFLOW ECO N O MIZ ER O PER ATI O N C YCLING DUR ATI O N INFO R M ATI O N
Each different equipment manufacturer may incorporate FDD monitoring of different data and operational characteristics to determine the above information. Most equipment manufacturers include options for FDD and fault alarm features built into the onboard equipment control systems. GENER AL A key to maintaining HVAC energy efficiency levels is ongoing equipment/system monitoring and regular maintenance services once the equipment has been properly sized, installed and commissioned. In all HVAC systems, potential operating faults may occur at any time. Some faults may be severe and lead to shutting down part or all of the system or unit. Other faults cause degradation in operating performance and efficiency, allowing the system or unit to run, but wasting energy, shortening equipment life, and compromising occupant comfort. The purpose of this Enhanced Criteria is to acknowledge the benefits of embedded, automated fault detection, and where feasible, diagnosis of common degradation faults in the operation of rooftop HVAC systems and heat pumps from 5 to 50 tons. Along with the fault detection and diagnosis functions, all diagnostic systems will include a reporting channel to an outside source so that corrective actions can be taken to restore the system to its optimal energy and environmental (indoor air quality and energy emissions-related) performance. Effectively, the embedded diagnostics are an automated, ongoing commissioning tool operating 24 x 7. Fault detection and diagnosis is fundamentally an adjunct function to the overall control system. FDD capabilities monitor a range of system conditions (e.g. refrigerant charge levels), and hardware status (e.g. sensor status), while some components are directly linked to control functions and settings (e.g. economizer operation). In larger rooftop units, most manufacturers offer optional communications modules to interconnect unit level diagnostic reporting to a DDC building energy management system.
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NON - ENERG Y BENEFIT S OF FD D
L o we r o p e r a t i o n a l a n d m a i n t e n a n c e c o s t s . By maintaining optimal
performance of the system, energy cost savings will occur over the life of the system. In addition, the fault detection features can actually decrease maintenance costs for a building owner by eliminating unnecessary maintenance costs. This same type of approach is now being incorporated into high-end automobiles and trucking fleets; these vehicles will actually monitor driving habits and engine performance, and extend maintenance periods in response to actual operation.
Eq u i p m e n t l i f e. By maintaining operational peak efficiency, the life of the system, and in particular the compressor, will be extended. I n d o o r a i r q u a l i t y a n d o c c u p a n t c o m f o r t . The ability to maintain proper
outside air flow to meet air quality and thermal comfort requirements is directly tied to the operating condition of the system and faults that may arise.
P r o p e r t y m a n a g e m e n t . Organizations that manage multiple properties would perceive a significant benefit by having this portion of building maintenance automated.
SA MPLE FD D CRITERIA
The following FDD framework should be reviewed and compared with the FDD functions that HVAC manufacturers already embed in their units of all sizes and efficiency levels or offer as an additional feature. The framework should also be compared with third party providers of FDD equipment. This is not an exclusive list of diagnostic functions. This list covers the minimum set in including refrigeration cycle, economizer and controls. These are the recommended minimum fault alarm set that should be specified in the HVAC equipment bid specification. At this time, there are limited models that would meet 100% of the FDD functions listed. However, HVAC equipment that meets the requirements of Criteria 2.9, Mechanical Equipment Efficiency (CEE Tier 2) will at minimum include the 75-80+% of the functions listed. Manufacturer’s technical manuals provide detailed descriptions of embedded and optional fault alarms functions. The means and methods of calculating, describing and reporting fault conditions are at the discretion of the manufacturer of the FDD product. The following information provides more detail on typically anticipated FDD system capabilities:
Include an automated mechanism for notifying when service on the unit is needed and describing the condition. Examples of notification mechanisms include an indicator light or electronic notice on premises in a visible place indicating the unit has a fault, a communications channel for email, pager, telephone or web-based notification or related two-way communications capability. Condition descriptions are at the manufacturer’s discretion.
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ENHANCED PERFORMANCE STRATEGIES ○ 3.14 FAULT DETECTION AND DIAGNOSTICS
Indicate the nature of the service required to restore performance recognizing that some faults have more than a single potential cause. Provide feedback on completed service work to validate that service was effective.
The unit controller will diagnose and send a fault signal for the following conditions:
SE VERE FAULT S
Failed compressor Failed evaporator fan motor Failed evaporator fan belt Failed condenser fan motor Sensor failure
D EG R ADATI O N FAU LT S
Option A: Steady-State Cooling Ef ficiency Indicator The FDD system will estimate and report steady state cooling efficiency within +/-10% of actual and indicate a fault when the estimated unit efficiency is below a user adjustable threshold. This approach provides a direct indication of ongoing energy performance. A reading outside the threshold level indicates a problem somewhere in the system that requires attention by service personnel. Option B: Fault Point Indicator The FDD system should detect and report as many of the following subsystem and component faults as possible. Controls Short cycling - on time [less than 5 minutes 10 or more times in 24 hours] Failed relief damper Simultaneous heating and cooling When conditions are favorable for economizer operation and economizer is not active When conditions are not favorable for economizer operation and economizer is active
Refrigerant Cycle/System Superheat and subcooling should be within a range indicating charge is correct, assuming other faults have been addressed.
Low refrigerant charge High refrigerant charge Air in refrigeration loop Restriction in refrigeration loop
ENHANCED PERFORMANCE STRATEGIES ○ 3.14 FAULT DETECTION AND DIAGNOSTICS
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AIR HAND LING S YS TEM / AIRFLOW
These fault conditions affect indoor air quality and reduce refrigeration cycle efficiency:
Dirty air fi lter Dirty evaporator coil Dirty condenser coil Reduced air flow Excessive air flow
New generation retrofit diagnostic packages are coming to market that provide a web-based user interface that provides 24x7 access to individual unit performance and diagnostics.
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ENHANCED PERFORMANCE STRATEGIES ○ 3.14 FAULT DETECTION AND DIAGNOSTICS
Section Four: Energy Modeling
4.1 Determine Performance with Energy Modeling
Energy modeling can be used to target increasing levels of whole building energy performance beyond the basic requirements of the Core Performance program. As a compliance path for Core Performance, energy modeling can also be used by projects to demonstrate equivalent performance using alternate energy savings strategies. The strategies identified in the Core Performance Guide represent an excellent starting point for projects targeting more aggressive energy savings.
Energy Modeling
Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies
4.1 Determine Performance with Energy Modeling
PURP OSE Provide an alternate method of demonstrating that the project achieves or exceeds the Advanced Buildings performance goals and allow for project customization within these goals. CRITERIA Sophisticated energy modeling software such as eQUEST, PowerDOE, Energy Plus, etc. may be used to demonstrate that the project has exceeded the prescriptive requirements of ASHRAE 90.1-2004 (in Vermont, the Vermont Commercial Energy Code) by 20% or more.
Energy Modeling Appendices
Good modeling programs will both graphically and statistically represent the differences between scenarios. Here, the projected monthly energ y use of a baseline and proposed building is compared.
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GENER AL The energy targets of Core Performance vary by climate, and local equivalence should be verified with program administrators. The baseline for Core Performance is based on the prescriptive requirements of ASHRAE 90.1-2004. The baseline for Core Performance Vermont Edition is based on the prescriptive requirements of the Vermont Commercial Energy Code. The USGBC uses the modeling guidelines of ASHRAE 90.1-2004 Appendix G as a baseline, and performance comparisons to the Appendix G baseline may result in different relative savings estimates compared to a prescriptive baseline. (Although projected energy use of the project itself should remain unchanged.)
LEED Relationship SS WE EA MR EQ credit 1
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ENERGY MODELING ○ 4.1 DETERMINE PERFORMANCE WITH ENERGY MODELING
Appendices
Appendix A: Acceptance Requirements for High Performance Buildings Appendix B: Climate Zone Map Appendix C: Acronyms and Definitions
Appendices
Introduction Design Process Strategies Core Performance Requirements
Appendix A: Acceptance Requirements for High Performance Buildings
PURP OSE AND S COPE This appendix defines acceptance procedures identified in Criteria 1.5 that must be completed as part of the Core Performance program. INTRODUC TION Acceptance Requirements are defined as the application of targeted inspection checks and functional and performance testing conducted to determine whether specific building components, equipment, systems, and interfaces between systems conform to the Criteria set forth in the Core Performance and to related construction documents (plans or specifications). Acceptance Requirements can effectively improve building performance and help determine whether equipment meets operational goals and whether it should be adjusted to increase efficiency and effectiveness. This section describes the process for completing the Acceptance Requirements. The steps include the following: Document plans showing sensor locations, devices, control sequences and notes Review the installation, perform acceptance tests and document results Document the operating and maintenance information, indicate test results on the Construction Certification, and submit the Certificate to the implementing agency prior to receiving final project approval
Enhanced Performance Strategies Energy Modeling Appendices
Acceptance testing is not intended to take the place of commissioning or test and balance procedures that a building owner might incorporate into a building project. It is an adjunct process focusing only on demonstrating equipment performance. The installing contractor, engineer of record or owner’s agent shall be responsible for reviewing the plans and specifications to assure they conform to the Acceptance Requirements. This is typically done prior to signing a Design Certification. The installing contractor, engineer of record or owner’s agent shall be responsible for providing all necessary instrumentation, measurement and monitoring, and undertaking all required acceptance requirement procedures. They shall be responsible for correcting all performance deficiencies and again implementing the acceptance requirement procedures until all specified systems and equipment are performing in accordance with the individual Criteria. The installing contractor, engineer of record or owner’s agent shall be responsible for documenting the results of the acceptance requirement procedures including paper and electronic copies of all measurement and monitoring results. They shall be responsible for performing data analysis, calculation of performance indices and crosschecking results with the requirements of the individual Criteria. They shall be responsible for issuing a Certificate of
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Acceptance. Implementing agencies shall not release a final project approval until a Certificate of Acceptance is submitted that demonstrates that the specified systems and equipment have been shown to be performing in accordance with the Criteria. The installing contractor, engineer of record or owner’s agent upon completion of undertaking all required acceptance requirement procedures shall record their Contractor’s License Number or their Professional Registration License Number on each Certificate of Acceptance that they issue.
A.1 Outdoor Air
A .1.1 VARIABLE AIR VOLUME ( VAV ) S YS TEMS OUTD O OR AIR ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following:
Outside air flow station is calibrated OR a calibration curve of outside air versus outside air damper position, inlet vane signal, or VFD signal was completed during system testing and balancing (TAB) procedures.
EQUIPMENT S TART- UP Ste p 1 : If the system has an outdoor air economizer, force the economizer high limit to disable
economizer control (e.g. for a fixed drybulb high limit, lower the setpoint below the current outdoor air temperature).
Ste p 2 : Drive all VAV boxes to the greater of the minimum airflow or 30% of the total design airflow. Verify and document the following:
Measured outside airflow CFM corresponds to no less than 90% of the total value determined in Credit 2.3. System operation stabilizes within 15 minutes after test procedures are initiated (no hunting).
Ste p 3 : Drive all VAV boxes to achieve design airflow. Verify and document the following:
Measured outside airflow CFM corresponds to no less than 90% of the total value determined in Credit 2.3. System operation stabilizes within 15 minutes after test procedures are initiated (no hunting).
A .1. 2 CONS TANT VOLUME S YSTEM OUTDOOR AIR ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following:
The system has a fixed or motorized minimum outdoor air damper, or an economizer capable of maintaining a minimum outdoor air damper position.
E Q U I PME N T T E S T I N G Ste p 1 : If the system has an outdoor air economizer, force the economizer high limit to disable
economizer control (e.g. for a fixed dry bulb high limit, lower the setpoint below the current outdoor air temperature).
Measured outside airflow CFM with damper at minimum position corresponds to no less than 90% of the total value determined in Credit 2.3.
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A.2 Packaged HVAC Systems
Acceptance requirements apply only to constant volume, direct expansion (DX) packaged systems with gas furnaces or heat pumps. A . 2.1 CONS TANT VOLUME PACK AGED HVAC S YS TEMS ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following:
Thermostat is located within the zone that the HVAC system serves Space temperature thermostat is factory-calibrated (proof required) or fieldcalibrated Appropriate temperature deadband has been programmed Appropriate occupied, unoccupied, and holiday schedules have been programmed. A one-hour pre-occupancy purge has been programmed Economizer lockout control sensor, if applicable, is factory-calibrated (proof required) or field-calibrated and setpoint properly set (refer to the economizers acceptance requirements section for detail) Demand control ventilation controller, if applicable, is factory-calibrated (proof required) or field-calibrated and setpoint properly set (refer to the demand control ventilation acceptance requirements section for detail)
E Q U I PME N T T E S T I N G Ste p 1 : Simulate heating load during occupied condition (e.g. by setting time schedule to
include actual time and placing thermostat heating setpoint below actual temperature). Verify and document the following:
Supply fan operates continually during occupied condition. Gas-fired furnace, heat pump or electric heater, if applicable, stages on. Outside air damper is open to the minimum position.
Ste p 2 : Simulate “no-load” during occupied condition (e.g. by setting time schedule to include actual time and placing thermostat heating setpoints above actual temperature and cooling setpoint below actual temperature). Verify and document the following:
Supply fan operates continually during occupied condition. Neither heating nor cooling are provided by the unit. Outside air damper is open to the minimum position.
Ste p 3 : If there is an economizer, simulate cooling load and economizer operation, if
applicable, during occupied condition (e.g. by setting time schedule to include actual time and placing thermostat cooling setpoint above actual temperature). Verify and document the following:
Supply fan operates continually during occupied condition. Refer to the economizers acceptance requirements section for testing protocols.
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Ste p 4 : If there is no economizer, simulate cooling load during occupied condition (e.g. by
setting time schedule to include actual time and placing thermostat cooling setpoint above actual temperature). Verify and document the following:
Supply fan operates continually during occupied condition. Compressor(s) stage on. Outside air damper is open to the minimum position.
Ste p 5 : Change the time schedule force the unit into unoccupied mode. Verify and document the following:
Supply fan turns off. Outside air damper closes completely.
Ste p 6 : Simulate heating load during setback conditions (e.g. by setting time schedule to
exclude actual time and placing thermostat setback heating setpoint below actual temperature). Verify and document the following:
Supply fan cycles on. Gas-fired furnace, heat pump or electric heater, if applicable, stages on. Supply fan cycles off when heating equipment is disabled.
Ste p 7: If there is an economizer, simulate cooling load and economizer operation, if applicable, during unoccupied condition (e.g. by setting time schedule to exclude actual time and placing thermostat setup cooling setpoint above actual temperature). Verify and document the following:
Supply fan cycles on. Refer to the economizers acceptance requirements section for testing protocols. Supply fan cycles off when call for cooling is satisfied (simulated by lowering the thermostat setpoint to below actual temperature). Outside air damper closes when unit cycles off.
Ste p 8 : If there is no economizer, simulate cooling load during setup condition (e.g. by setting
time schedule to exclude actual time and placing thermostat setup cooling setpoint above actual temperature). Verify and document the following:
Supply fan cycles on. Compressor(s) stage on to satisfy cooling space temperature setpoint. Supply fan cycles off when cooling equipment is disabled.
Ste p 9 : Simulate manual override during unoccupied condition (e.g. by setting time schedule to
exclude actual time or by pressing override button). Verify and document the following: System reverts to “occupied” mode and operates as described above to satisfy a heating, cooling, or no load condition. System turns off when manual override time period expires.
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A.3 Air Distribution Systems
Acceptance requirements apply only to package unitary systems. A . 3.1 AIR DIS TRIBUTION ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following:
Drawbands are either stainless steel worm-drive hose clamps or UV-resistant nylon duct ties. Flexible ducts are not constricted in any way (for example, pressing against immovable objects or squeezed through openings). Duct leakage tests shall be performed before access to ductwork and associated connections are blocked by permanently installed construction material. Joints and seams are not sealed with a cloth back rubber adhesive tape unless used in combination with mastic and drawbands. Duct R-values are verified. Insulation is protected from damage and suitable for outdoor service if applicable.
E Q U I PME N T T E S T I N G Ste p 1 : Perform duct leakage test per California’s 2003 Nonresidential ACM Approved Manual,
Appendix G, Section 4.3.8.2. Certify the following:
Duct leakage is less than 6% if a new building and 12% if existing ductwork.
Ste p 2 : Obtain third-party field verification.
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A.4 Lighting Control Systems
Lighting control testing is performed on:
Manual Daylighting Controls. Automatic Daylighting Controls. Occupancy Sensors. Automatic Time-switch Control.
A .4.1 AUTOM ATIC DAY LIGHTING CONTROL S ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following: All control devices (photocells) have been properly located, factory-calibrated (proof required) or field-calibrated and set for appropriate set points and threshold light levels. Installer has provided documentation of setpoints, setting and programming for each device. Luminaires located in either a horizontal daylit area(s) or a vertical daylit area(s) are powered by a separate lighting circuit from non-daylit areas.
E Q U I PME N T T E S T I N G
Continuous Dimming Control Systems
Ste p 1 : Simulate bright conditions for a continuous dimming control system. Verify and
document the following: Lighting power reduction is at least 65% under fully dimmed conditions. At least one control step reduces the lighting power by at least 30%. Only luminaires in daylit zone are affected by daylight control. Automatic daylight control system reduces the amount of light delivered to the space uniformly. Dimming control system provides reduced fl icker operation over the entire operating range. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
Ste p 2 : Simulate dark conditions for a continuous dimming control system. Verify and
document the following: Automatic daylight control system increases the amount of light delivered to the space uniformly. Dimming control system provides reduced fl icker operation over the entire operating range. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
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Stepped Dimming Control Systems
Ste p 1 : Simulate bright conditions for a stepped dimming control system. Verify and document
the following: Lighting power reduction is at least 50% under fully dimmed conditions. Only luminaires in daylit zone are affected by daylight control. Automatic daylight control system reduces the amount of light delivered to the space relatively uniformly. Automatic daylight control system reduces the amount of light delivered to the space per manufacturer’s specifications for power level versus light level. Minimum time delay between step changes is 3 minutes to prevent short cycling. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
Ste p 2 : Simulate dark conditions for a stepped dimming control system. Verify and document the following:
Automatic daylight control system increases the amount of light delivered to the space per manufacturer’s specifications for power level versus light level. Stepped dimming control system provides reduced fl icker over the entire operating range. Minimum time delay between step changes is 3 minutes to prevent short cycling. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
Stepped Switching Control Systems
Ste p 1 : Simulate bright conditions for a stepped switching control system. Verify and
document the following: Lighting power reduction is at least 50% under fully switched conditions.. Only luminaires in daylit zone are affected by daylight control. Automatic daylight control system reduces the amount of light delivered to the space relatively uniformly. Automatic daylight control system reduces the amount of light delivered to the space per manufacturer’s specifications for power level versus light level. Single- or multiple-stepped switching controls provide a dead band of at least three minutes between switching thresholds to prevent short cycling. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
Ste p 2 : Simulate dark conditions for a stepped switching control system. Verify and document
the following: Automatic daylight control system increases the amount of light delivered to the space per manufacturer’s specifications for power level versus light level. Single- or multiple-stepped switching controls provide a dead band of at least three minutes between switching thresholds to prevent short cycling. Illuminance measurements in the space, location of measurements and specific device settings, program settings and other measurements are documented.
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A .4. 2 O CCUPANC Y SENS OR ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following: Occupancy sensitivity has been located to minimize false signals. Occupancy sensors do not encounter any obstructions that could adversely affect desired performance. Ultrasound occupancy sensors do not emit audible sound.
E Q U I PME N T T E S T I N G Ste p 1 : For a representative sample of building spaces, simulate an unoccupied condition.
Verify and document the following: Lights controlled by occupancy sensors turn off within a maximum of 30 minutes from the start of an unoccupied condition. The occupant sensor does not trigger a false “on” from movement in an area adjacent to the controlled space or from HVAC operation. Signal sensitivity is adequate to achieve desired control.
Ste p 2 : For a representative sample of building spaces, simulate an occupied condition. Verify and document the following:
Status indicator or annunciator operates correctly. Lights controlled by occupancy sensors turn on immediately upon an occupied condition, OR sensor indicates space is “occupied” and lights are turned on manually (automatic OFF and manual ON control strategy).
A .4. 3 M ANUAL DAY LIGHTING CONTROL S ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following:
If dimming ballasts are specified for light fixtures within the daylit area, make sure they meet all the Standards requirements, including “reduced fl icker operation” for manual dimming control systems.
E Q U I PME N T T E S T I N G Ste p 1 : Perform manual switching control. Verify and document the following:
Manual switching or dimming achieves a lighting power reduction of at least 50%. The amount of light delivered to the space is uniformly reduced.
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A .4.4 AUTOM ATIC TIME SWITCH CONTROL ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following:
Automatic time switch control is programmed with acceptable weekday, weekend, and holiday (if applicable) schedules. Document for the owner automatic time switch programming including weekday, weekend, and holiday schedules as well as all set-up and preference program settings. Verify the correct time and date is properly set in the time switch. Verify the battery is installed and energized. Override time limit is no more than 2 hours.
E Q U I PME N T T E S T I N G Ste p 1 : Simulate occupied condition. Verify and document the following:
All lights can be turned on and off by their respective area control switch. Verify the switch only operates lighting in the ceiling-height partitioned area in which the switch is located.
Ste p 2 : Simulate unoccupied condition. Verify and document the following:
All non-exempt lighting turn off. Manual override switch allows only the lights in the selected ceiling height partitioned space where the override switch is located, to turn on or remain on until the next scheduled shut off occurs. All non-exempt lighting turns off.
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A.5 Air Economizer Controls
Economizer testing is performed on all built-up systems and on packaged unitary systems. Air economizers installed by the HVAC system manufacturer and certified as being factorycalibrated and tested do not require field testing. A . 5.1 ECONOMIZER ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following: Economizer lockout setpoint complies with Criteria 2.13. System controls are wired correctly to ensure economizer is fully integrated (i.e. economizer will operate when mechanical cooling is enabled). Economizer lockout control sensor location is adequate (open to air but not exposed to direct sunlight nor in an enclosure; away from sources of building exhaust; at least 25 feet away from cooling towers). Relief fan system (if applicable) operates only when the economizer is enabled. If no relief fan system is installed, barometric relief dampers are installed to relieve building pressure when the economizer is operating.
E Q U I PME N T T E S T I N G Ste p 1 : Simulate a cooling load and enable the economizer by adjusting the lockout control
(fixed or differential dry-bulb or enthalpy sensor depending on system type) setpoint. Verify and document the following:
Economizer damper modulates opens to maximum position to satisfy cooling space temperature setpoint. Return air damper modulates closed and is completely closed when economizer damper is 100% open. Economizer damper is 100% open before mechanical cooling is enabled. Relief fan is operating or relief dampers freely swing open. Mechanical cooling is only enabled if cooling space temperature setpoint is not met with economizer at 100% open. Doors are not pushed ajar from over pressurization.
Ste p 2 : Continue from Step 1 and disable the economizer by adjusting the lockout control (fixed or differential dry-bulb or enthalpy sensor depending on system type) setpoint. Verify and document the following:
Economizer damper closes to minimum position. Return air damper opens to normal operating position. Relief fan shuts off or relief dampers close. Mechanical cooling remains enabled until cooling space temperature setpoint is met.
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A.6 Demand Control Ventilation (DCV) Systems
A .6.1 PACK AGED S YS TEMS D C V ACCEP TANCE
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following: Carbon dioxide control sensor is factory calibrated (proof required) or fieldcalibrated with an accuracy of no less than 75 ppm. The sensor is located in the room between 1 ft and 6 ft above the floor. System controls are wired correctly to ensure proper control of outdoor air damper system.
E Q U I PME N T T E S T I N G
demand control ventilation controller setpoint below ambient CO2 levels. Verify and document the following:
Ste p 1 : Simulate a high CO2 load and enable the demand control ventilation by adjusting the
Outdoor air damper modulates open per Standards to maximum position to satisfy outdoor air requirements specified in Criteria 2.3.
Ste p 2 : Continue from Step 1 and disable demand control ventilation by adjusting the demand control ventilation controller setpoint above ambient CO2 levels. Verify and document the following:
Outdoor air damper closes to minimum position.
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A.7 Variable Frequency Drive Systems
A .7.1 SUPPLY FAN VARIABLE FLOW CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Performance Testing, verify and document the following: Discharge static pressure sensor is factory calibrated (proof required) or fieldcalibrated with secondary source. Disable discharge static pressure reset sequences to prevent unwanted interaction while performing tests.
E Q U I PME N T T E S T I N G Ste p 1 : Drive all VAV boxes to achieve design airflow. Verify and document the following:
Witness proper response from supply fan (e.g. VFD ramps up to full speed; inlet vanes open full). Supply fan maintains discharge static pressure within +/-10% of setpoint. Measured maximum airflow corresponds to design and/or TAB report within +/-10%. System operation stabilizes within a reasonable amount of time after test procedures are initiated (no hunting).
Ste p 2 : Drive all VAV boxes to minimum flow or to achieve 30% total design airflow
whichever is larger. Verify and document the following: Witness proper response from supply fan (VFD slows fan speed; inlet vanes close). Supply fan maintains discharge static pressure within +/-10% of setpoint. System operation stabilizes within a reasonable amount of time after test procedures are initiated (no hunting).
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A.8 Hydronic System Controls Acceptance
Hydronic controls Acceptance Testing will be performed on:
Variable Flow Controls Automatic Isolation Controls Supply Water Temperature Reset Controls Water-loop Heat Pump Controls Variable Frequency Drive Control
A . 8.1 VARIABLE FLOW CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following: Valve and piping arrangements were installed per the design drawings to achieve flow reduction requirements. Installed valve and hydronic connection pressure ratings meet specifications. Installed valve actuator torque characteristics meet specifications.
E Q U I PME N T T E S T I N G Ste p 1 : Open all control valves. Verify and document the following:
System operation achieves design conditions.
Ste p 2 : Initiate closure of control valves. Verify and document the following:
The design pump flow control strategy achieves flow reduction requirements. Ensure all valves operate correctly against the minimum flow system pressure condition.
A . 8. 2 AUTOM ATIC IS OL ATION CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following: Valve and piping arrangements were installed per the design drawings to achieve equipment isolation requirements. Installed valve and hydronic connection pressure ratings meet specifications. Installed valve actuator torque characteristics meet specifications.
E Q U I PME N T T E S T I N G Ste p 1 : Open all control valves. Verify and document the following:
System operation achieves design conditions.
Ste p 2 : Initiate shut-down sequence on individual pieces of equipment. Verify and document the following:
The design control strategy meets isolation requirements automatically upon equipment shut-down. Ensure all valves operate correctly at shut-off system pressure conditions.
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A . 8. 3 SUPPLY WATER TEMPER ATURE RE SE T CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following:
All sensors have been calibrated. Sensor locations are adequate to achieve accurate measurements. Installed sensors comply with specifications.
E Q U I PME N T T E S T I N G Ste p 1 : Manually change design control variable to maximum setpoint. Verify and document
the following:
Chilled or hot water temperature setpoint is reset to appropriate value. Actual supply temperature changes to meet setpoint.
Ste p 2 : Manually change design control variable to minimum setpoint. Verify and document the following:
Chilled or hot water temperature setpoint is reset to appropriate value. Actual supply temperature changes to meet setpoint.
A . 8.4 WATER- LO OP HE AT PUMP CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following:
Valves were installed per the design drawings to achieve equipment isolation requirements. Installed valve and hydronic connection pressure ratings meet specifications. Installed valve actuator torque characteristics meet specifications. All sensor locations comply with design drawings. All sensors are calibrated. VFD minimum speed setpoint exceeds motor manufacturer’s requirements. VFD minimum speed setpoint should not be set below the pumping energy curve inflection point (i.e. combination of pump-motor-VFD efficiency at reduced load may cause power requirements to increase upon further reduction in load).
E Q U I PME N T T E S T I N G Ste p 1 : Open all control valves. Verify and document the following:
System operation achieves design conditions +/- 5%. VFD operates at 100% speed at full flow conditions.
Ste p 2 : Initiate shut-down sequence on each individual heat pumps. Verify and document the following:
Isolation valves close automatically upon unit shut-down. Ensure all valves operate correctly at shut-off system pressure conditions. Witness proper response from VFD (speed decreases as valves close). System operation stabilizes within 5 minutes after test procedures are initiated (no hunting).
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Ste p 3 : Adjust system operation to achieve 50% flow. Verify and document the following:
VFD input power less than 30% of design.
Ste p 4 : Adjust system operation to achieve a flow rate that would result in the VFD operating below minimum speed setpoint. Verify and document the following:
Ensure VFD maintains minimum speed setpoint regardless of system flow operating point.
A . 8. 5 VARIABLE FREQUENC Y DRIVE CONTROL S
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following:
All valves, sensors, and equipment were installed per the design drawings. All installed valves, sensors, and equipment meet specifications. All sensors are calibrated. VFD minimum speed setpoint exceeds motor manufacturer’s requirements. VFD minimum speed setpoint should not be set below the pumping energy curve inflection point (i.e. combination of pump-motor-VFD efficiency characteristics at reduced load may cause input power to increase upon further reduction in load).
E Q U I PME N T T E S T I N G Ste p 1 : Open all control valves. Verify and document the following:
System operation achieves design conditions +/- 5%. VFD operates at 100% speed at full flow conditions.
Ste p 2 : Modulate control valves closed. Verify and document the following:
Ensure all valves operate correctly at system operating pressure conditions. Witness proper response from VFD (speed decreases as valves close). System operation stabilizes within 5 minutes after test procedures are initiated (no hunting).
Ste p 3 : Adjust system operation to achieve 50% flow. Verify and document the following:
VFD input power less than 30% of design.
Ste p 4 : Adjust system operation to achieve a flow rate that would result in the VFD operating below minimum speed setpoint. Verify and document the following:
Ensure VFD maintains minimum speed setpoint regardless of system flow operating point.
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A.9 Trend-Logging Specifications
Trend-Logging Acceptance Testing will be performed on the following critical pieces of equipment:
Air handling units Variable air volume boxes Chillers
Generic requirements outlined in the Construction Inspections sections below pertain to each system. Equipment-Specific Acceptance Testing procedures are outlined in the Equipment Testing section. A .9.1 CONTRO L S YS TE M TE S TING
CO NS T R U C T I O N I NSPE C T I O N
Prior to Acceptance Testing, verify and document the following: All sensors installed met specifications All sensors were installed per the design drawings. All test ports and calibration wells were installed per the design drawings. All sensors have been calibrated (i.e. 3-point calibration, relative calibration, review calibration certificates and spot check sensors at random, etc.). Point-to-point check out performed on all sensors to be trended.
E Q U I PME N T T E S T I N G
Air Handling Units
Ste p 1 : Verify the following points are being trended with the specified time interval:
Temperatures – outside air, return air, mixed air, discharge air, downstream of heating coil, downstream of cooling coil. Setpoints – discharge air temperature, discharge pressure, mixed air temperature (if applicable), minimum ventilation airflow rate. Flow – minimum ventilation airflow. Pressure – discharge pressure. Status – cooling coil valve command, heating coil valve command.
Ste p 2 : Analyze trend data. Verify and document the following:
Ensure minimum outside air ventilation requirements are satisfied under all operating conditions. Ensure discharge air temperature satisfies setpoint without hunting. Ensure discharge air temperature setpoint is reset per design control sequences (if applicable). Ensure economizer functions per design control sequences. Ensure heating coil valve is commanded closed before outside airflow increases above minimum ventilation requirements. Ensure heating coil valve, economizer, and cooling coil valve all modulate in sequence to satisfy design control sequences without hunting. Ensure heating coil valve is not leaking by comparing valve position with air temperature downstream on heating coil. Ensure cooling coil valve is not leaking by comparing valve position with air temperature downstream on cooling coil. Ensure discharge air pressure satisfies setpoint without hunting.
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Variable Air Volume Boxes
Ste p 1 : Verify the following points are being trended with the specified time interval:
Temperatures – zone air, discharge air. Setpoints – occupied and unoccupied zone air, cooling maximum and minimum flow rate, heating maximum and minimum flow rate. Flow – cooling maximum and minimum flow rate, heating maximum and minimum flow rate. Status – primary air damper command, heating coil valve command (if applicable), fan command (if applicable).
Ste p 2 : Analyze trend data. Verify and document the following:
Ensure cooling maximum and minimum flow rates meet design. Ensure heating maximum and minimum flow rates meet design. Ensure zone air temperature satisfies both occupied and unoccupied setpoint without hunting. Ensure primary air flow is at cooling minimum before reheat coil valve commanded open. Ensure VAV box responds per design control sequences during unoccupied hours (for example fan shut off, primary air damper closed, etc.). Ensure VAV box fan (if applicable) responds per design control sequences and manufacturer’s specifications.
Chillers
Ste p 1 : Verify the following points are being trended with the specified time interval::
Temperatures – chilled water supply, chilled water return, condenser water supply, condenser water return. Setpoints – chilled water supply. Condenser water return. Pressure – evaporator differential, condenser differential. Power (or points that allow calculation of power) – input kW.
Ste p 2 : Analyze trend data. Verify and document the following:
Ensure chilled water supply temperature satisfies setpoint without hunting. Ensure chilled water supply temperature setpoint is reset per design control sequences. Ensure condenser water return temperature satisfies setpoint without hunting. Ensure condenser water return temperature setpoint is reset per design control sequences (if applicable).
Ste p 3 : Perform the following calculations:
Trend chilled water supply temperature, chilled water return temperature, evaporator differential pressure, and chiller input kW. Using manufacturer’s data, determine chilled water flow rate based on evaporator pressure drop. Calculate chilled water load based on temperature differential and flow rate. Use chilled water load and measured input kW to monitor system efficiency (kW/ton).
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Appendix B: Climate Zone Map
Climate Zones are defined primarily by heating or cooling loads, then by type (marine, Dry, Moist), creating a set of climate bands spanning the country.
Courtesy US Department of Energy, Office of Building Technologies, State and Federal Programs
Appendices
Introduction
Energy Modeling
Design Process Strategies
Core Performance Requirements
Enhanced Performance Strategies
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Introduction Design Process Strategies Core Performance Requirements Enhanced Performance Strategies Energy Modeling Appendices
Appendix C: Acronyms and Definitions
The following definitions apply throughout the Guidelines: 1.1 ACRON YMS
A SHR AE – American Society of Heating, Refrigerating and Air-conditioning Engineers H VAC – Heating, Ventilating and Air Conditioning IECC – International Energy Conservation Code IE SNA – Illuminating Engineering Society of North America LEED – Leadership in Energy and Environmental Design US G BC – US Green Buildings Council VAV – Variable Air Volume VSD – Variable Speed Drive
1. 2 DEFINITIONS
b a l l a s t : a device used in conjunction with an electric-discharge lamp to cause the lamp to start
and operate under the proper circuit conditions of voltage, current, wave form, electrode heat, etc.
b o i l e r : a self-contained low-pressure appliance for supplying steam or hot water. b u i l d i n g e nve l o p e : The elements of a building which enclose conditioned spaces through which thermal energy is capable of being transferred to or from the exterior or to or from unconditioned spaces. B u i l d i n g I n f o r m a t i o n M o d e l i n g ( BIM ) : a building modeling and information tool developed for the construction industry to allow information sharing across all providers and facets of a project using a common database. It is available from several providers. c f m : cubic feet per minute. c o e f f i c i e n t o f p e r f o r m a n c e ( CO P ) – c o o l i n g : the ratio of the rate of heat removal to the rate of
energy input, in consistent units, for a complete refrigeration system or some specific portion of that system under designated operating conditions.
c o n d u c t a n c e : see thermal conductance. c o n s t r u c t i o n d o c u m e n t s : drawings and specifications used to construct a building, building systems, or portions thereof. c o n t i n u o u s i n s u l a t i o n ( c o n t . i n s . o r c i ) : insulation that is continuous across all structural 122
members without thermal bridges other than fasteners and service openings. It is installed on the interior, exterior, or is integral to any opaque surface of the building envelope.
c o n t r o l d e v i c e : a specialized device used to regulate the operation of equipment. c r i t i c a l d e m a n d p e r i o d : the period of peak electricity or natural gas demand, as defined by a utility tariff, that establishes annual system peak load. The critical demand period is different from typical demand periods as traditionally defined by utility tariffs. d ay l i t a r e a : building floor area in proximity to glazing that is affected by natural daylight.
Daylit area relative to glazing is generally defined as follows:
( a ) ve r t i c a l g l a z i n g : the daylit area extends perpendicularly from the wall 1.5 times
the head height of the glazing, or to the nearest 60-inch or higher opaque partition, whichever is less; and a width of the window plus either 2 feet on each side.
( b ) h o r i z o n t a l g l a z i n g : the daylit area is the footprint of the skylight well at the ceiling
plus, in each of the lateral and longitudinal dimensions of the skylight, a distance of 0.75 times the ceiling height from the edge of the skylight well.
d ay l i g h t g l a z i n g : exterior glazing over 6 feet above the finished floor. d e m a n d : the highest amount of power (average kW over an interval) recorded for a building or
facility in a selected time frame.
D e m a n d Co n t r o l Ve n t i l a t i o n ( D C V ) : A system of control based on real-time monitoring of
carbon dioxide (CO2) to either insure indoor air quality and/or reduce energy consumption in unoccupied spaces.
d e s i g n c o n d i t i o n s : specified environmental conditions, such as temperature and light intensity,
required to be produced and maintained by a system and under which the system must operate.
d i s t r i b u t i o n s y s t e m : conveying means, such as ducts, pipes, and wires, to bring energy from a source to the point of use. The distribution system includes such auxiliary equipment as fans, pumps, and transformers. d o o r : all operable opening areas (which are not fenestration) in the building envelope, including
swinging and roll-up doors, fire doors, and access hatches. Doors that are more than one-half glass are considered fenestration. (See fenestration.) For the purposes of determining building envelope requirements, the classifications are defined as follows:
( a ) n o n - s w i n g i n g : roll-up, sliding, and all other doors that are not swinging doors. ( b ) s w i n g i n g : all operable opaque panels with hinges on one side and opaque revolving doors. d o o r a r e a : total area of the door measured using the rough opening and including the door slab
and the frame. (See fenestration area.)
DX – D i r e c t E x p a n s i o n : Refers to cooling systems that pass the air to be cooled directly over refrigerant cooling coils rather than using an intermediary fluid, such as water. e c o n o m i z e r, a i r : a duct and damper arrangement and automatic control system that together
allow the use of outside air directly to reduce or eliminate the need for mechanical cooling during mild or cold weather.
ERV – E n e r g y Re c ove r y Ve n t i l ato r : A device that uses heat and moisture exchangers to transfer
both sensible and latent heat between the supply air and return air to minimize energy use and improve comfort. See also HRV.
e f f i c i e n c y : actual performance compared to ideal performance at specified rating conditions. e m i t t a n c e : the ratio of the radiant energy emitted by a specimen to that emitted by an ideal
blackbody at the same temperature and under the same conditions.
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e n e r g y : the capacity for doing work. It takes a number of forms that may be transformed from one into another such as thermal (heat), mechanical (work), electrical, and chemical. Customary measurement units are British thermal units (Btu) and watt hours (Wh) where 1 Wh = 3.413 Btu. e n e r g y e f f i c i e n c y r a t i o ( EER ) : the ratio of net cooling capacity in Btu/h to total rate of electric
input in watts under designated operating conditions. (See coefficient of performance (COP)— cooling.)
e n e r g y p e r f o r m a n c e r a t i n g : the energy use of a proposed building under simulated operating conditions normalized for a specific variable. Projected energy use targets can be used for buildings in the design or construction process. Examples include kBtu/sf/yr, $/sf/yr, $/gross sales, Energy Performance Rating Score (US EPA), or like expressions of energy performance. EPAc t 05 : federal energy policy act adopted in 2005. EPAct05 provides a number of important
incentives to reduce energy costs for institutional and commercial buildings.
FD D – Fa u l t D e t e c t i o n a n d D i a g n o s t i c s : software, typically embedded in building operations
software, that identifies and, if possible, diagnoses faults in building equipment and/or operations. Some packages also take remedial action automatically.
f e n e s t r a t i o n : all areas (including the frames) in the building envelope that let in light, including windows, plastic panels, clerestories, skylights, glass doors that are more than onehalf glass, and glass block walls. (See building envelope and door.) A skylight is a fenestration surface having a slope of less than 60 degrees from the horizontal plane. Other fenestration, even if mounted on the roof of a building, is considered vertical fenestration. f e n e s t r a t i o n a r e a : total area of the fenestration measured using the rough opening and
including the glazing, sash, and frame. For doors where the glazed vision area is less than 50% of the door area, the fenestration area is the glazed vision area. For all other doors, the fenestration area is the door area.
f i x t u r e : the component of a luminaire that houses the lamp or lamps (and ballast if present),
positions the lamp, shields it from view, and distributes the light. The fixture also provides for connection to the power supply.
f l u e d a m p e r : a device in the flue outlet or in the inlet of or upstream of the draft control device of an individual, automatically operated, fossil fuel-fired appliance that is designed to automatically open the flue outlet during appliance operation and to automatically close the flue outlet when the appliance is in a standby condition. F-v a l u e : value of the heat loss through the edge and body of a slab-on-grade floor expressed
in terms of Btu/hrF per linear foot of perimeter. It represents the integral of all the various pathways heat travels out of the slab.
h e a t i n g s e a s o n a l p e r f o r m a n c e f a c t o r ( HSPF ) : the total heating output of a heat pump during its normal annual usage period for heating (in Btu) divided by the total electric energy input (in kWh) during the same period. HRV – H e a t R e c o ve r y Ve n t i l a t o r : A device that uses a heat exchanger to transfer sensible heat
between the supply air and return air flows to minimize energy use and improve comfort. See also ERV.
H VAC s y s t e m : Heating, Ventilation, and Air Conditioning; the equipment, distribution
systems, and terminals that provide, either collectively or individually, the processes of heating, ventilating, or air conditioning to a building or portion of a building.
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i n f i l t r a t i o n : the uncontrolled inward air leakage into a building caused by pressure differences
across these elements due to factors such as wind, inside and outside temperature differences (stack effect), and/or imbalance between supply and exhaust air systems.
i n t e g r a t e d p a r t- l o a d v a l u e ( IPLV ) : a single-number figure of merit based on part-load EER,
COP, or kW/ton expressing part-load efficiency for air-conditioning and heat pump equipment on the basis of weighted operation at various load capacities for the equipment.
k i l o w a t t ( k W ) : the basic unit of electric power, equal to 1000 W and 3413 Btu/h. l a b e l e d : equipment or materials to which a symbol or other identifying mark has been attached by the manufacturer indicating compliance with specified standards or performance in a specified manner. l a m p : a generic term for a man-made light source often called a bulb or tube. ( a ) c o m p a c t f l u o r e s c e n t l a m p : a fluorescent lamp of a small compact shape, with a single
base that provides the entire mechanical support function.
( b ) f l u o r e s c e n t l a m p : a low-pressure electric discharge lamp in which a phosphor coating
transforms some of the ultraviolet energy generated by the discharge into light.
( c ) g e n e r a l s e r v i c e l a m p : a class of incandescent lamps that provide light in virtually all
directions. General service lamps are typically characterized by bulb shapes such as A, standard; S, straight side; F, flame; G, globe; and PS, pear straight.
( d ) h i g h - i nte n s i t y d i s c h a r g e ( HID ) l a m p : an electric discharge lamp in that light is
produced when an electric arc is discharged through a vaporized metal such as mercury or sodium. Some HID lamps may also have a phosphor coating that contributes to the light produced or enhances the light color.
( e ) i n c a n d e s c e n t l a m p : a lamp in which light is produced by a fi lament heated to
incandescence by an electric current.
( f ) r e f l e c t o r l a m p : a class of incandescent lamps that have an internal reflector to direct
the light. Reflector lamps are typically characterized by reflector shapes such as R, reflector; ER, ellipsoidal reflector; PAR, parabolic aluminized reflector; MR, multifaceted reflector; and others.
l i g h t i n g s y s t e m : a group of luminaires circuited or controlled to perform a specific function. l i g h t i n g p o we r d e n s i t y ( LPD ) : the connected lighting load power (in Watts) per unit area. Calculation of LPD includes combined energy use of lamp and ballast systems. It is typically characterized by building classification or space function and is used as an energy code limit value for a given building type or space use. m e c h a n i c a l c o o l i n g : reducing the temperature of a gas or liquid by using vapor compression,
absorption, desiccant dehumidification combined with evaporative cooling, or another energydriven thermodynamic cycle. Indirect or direct evaporative cooling alone is not considered mechanical cooling.
o c c u p a n t s e n s o r : a device that detects the presence of people within an area. o p a q u e e nve l o p e : all areas in the building envelope, except fenestration and building service openings such as vents and grilles. (See building envelope and fenestration.)
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o p e r a t i o n a l p e r f o r m a n c e r e q u i r e m e n t s : A written document that details the functional
requirements of a project and the expectations of how it will be used and operated. This includes project and design goals, measurable performance Criteria, budgets, schedules, success Criteria and supporting information.
o r i e n t a t i o n : the direction an envelope element faces relative to know referent, such as True
North, i.e., the relative direction of a vector perpendicular to and pointing away from the surface outside of the element.
OA o r O S A - o u t d o o r ( o u t s i d e ) a i r : air that is outside the building envelope or is taken from
outside the building that has not been previously circulated through the building.
p r o j e c t i o n f a c t o r ( PF ) : the ratio of the horizontal depth of the external shading projection divided
by the sum of the height of the fenestration and the distance from the top of the fenestration to the bottom of the farthest point of the external shading projection, in consistent units.
p r o p o s e d d e s i g n : a computer representation of the actual proposed building design or portion
thereof used as the basis for calculating the design energy cost.
P TAC – P a c k a g e d Te r m i n a l A i r C o n d i t i o n i n g u n i t s : also known as “window-shakers, a factoryselected combination of heating and cooling components, assemblies or sections intended to serve a single room or zone. R-v a l u e o f i n s u l a t i o n : the thermal resistance of the insulation alone as specified by the
manufacturer in units of h·ft2·°F/Btu at a mean temperature of 75°F. Rated R-value refers to the thermal resistance of the added insulation in framing cavities or insulated sheathing only and does not include the thermal resistance of other building materials or air films. (See thermal resistance.)
r e c o r d d r a w i n g s : drawings that record the conditions of the project as constructed. These
include any refinements of the construction or bid documents (often referred to as “as-builts”.
r e f l e c t a n c e : the percentage of the light reflected by a surface relative to the light incident upon it. r o o f : the upper portion of the building envelope, including opaque areas and fenestration, that is horizontal or tilted at an angle of less than 60° from horizontal. s e a s o n a l e n e r g y e f f i c i e n c y r a t i o ( SEER ) : the total cooling output of an air conditioner during its normal annual usage period for cooling (in Btu) divided by the total electric energy input during the same period (in Wh). u t i l i t y s e r v i c e : the equipment for delivering energy from the supply or distribution system to
the premises served.
s i n g l e -z o n e s y s t e m : an HVAC system serving a single HVAC zone. s k y l i g h t : see fenestration. s o l a r h e a t g a i n c o e f f i c i e n t ( SH G C ) : the ratio of the solar heat gain entering the space through
the fenestration area to the incident solar radiation. Solar heat gain includes directly transmitted solar heat and absorbed solar radiation, which is then reradiated, conducted, or convected into the space. (See fenestration area.)
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s p a c e : an enclosed space within a building. Spaces are defined as follows for the purpose of
determining building envelope requirements.
( a ) c o n d i t i o n e d s p a c e : a heated or cooled space, or both, within a building and, where
required, provided with humidification or dehumidification means so as to be capable of maintaining a space condition falling within the comfort envelope set forth in ASHRAE 55.
( b ) u n c o n d i t i o n e d s p a c e : a space other than a conditioned space. s y s t e m : a combination of equipment and auxiliary devices (e.g., controls, accessories, interconnecting means, and terminal elements) by which energy is transformed so it performs a specific function such as HVAC, service water heating, or lighting. TAB – Te s t a n d B a l a n c e : the process of verifying and calibrating the air flow through a building air conditioning system under varying operating conditions. t h e r m a l r e s i s t a n c e ( R-v a l u e ) : the reciprocal of the time rate of heat flow through a unit
area induced by a unit temperature difference between two defined surfaces of material or construction under steady-state conditions. Units of R are h·ft2·°F/Btu.
t h e r m o s t a t i c c o n t r o l : an automatic control device or system used to maintain temperature at a
fixed or adjustable set point.
t i n t e d : (as applied to fenestration) coloring that is integral to the glazing material. Tinting does not include surface applied fi lms such as reflective coatings, applied either in the field or during the manufacturing process. To n : a unit of cooling equal to 12,000 Btu. Derived from the amount of heat absorbed by a ton of ice while melting. U -f a c t o r ( t h e r m a l t r a n s m i t t a n c e ) : heat transmission in unit time through unit area of a
material or construction and the boundary air fi lms, induced by unit temperature difference between the environments on each side. Units of U are Btu/h·ft2·°F.
u n i t a r y e q u i p m e n t : one or more factory-made assemblies that normally include an evaporator
or cooling coil and a compressor and condenser combination. Units that perform a heating function are also included.
VAV – Va r i a b l e A i r Vo l u m e : a system designed to supply only the volume of conditioned air to a space that is needed to satisfy the thermal or ventilation load, saving fan energy. ve n t i l a t i o n : the process of supplying fresh air by natural or mechanical means to or from any space. V i s i b l e L i g h t Tr a n s m i t t a n c e ( V LT ) : a measure of the percentage (0-100%) of visible light
transmitted by the glazing.
V S D ( v a r i a b l e s p e e d d r i ve ) o r V FD ( v a r i a b l e f r e q u e n c y d r i ve ) o r A SD ( a d j u s t a b l e s p e e d d r i ve ) : an electronic controller that allows an electric motor to operate over a range of speeds.
Typically used on fans and pumps in variable flow systems.
w a l l a r e a , g r o s s : the area of the wall measured on the exterior face from the top of the floor to the bottom of the roof. w a r m - u p : increase in space temperature to occupied set point after a period of shutdown or setback. Reprinted by permission of American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., from ANSI/ASHRAE/IESNA Standard 90.1-2001. Copyright 2001 ASHRAE (www.ashrae.org). This material may not be copied nor distributed in either paper or digital form without ASHRAE’s permission.
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