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Site Planning & Management

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Introduction The Darrick Wood School is our current client located in Orpington, Kent. The project required to cover involves having to newly build, design and pursue works of infrastructure and external works in order to come to completion of an erection to a two storey sixth form centre which is to be compromised along with classrooms, a library, common rooms and associated offices. The other aspects which are also required to work on as instructed to pursue additionally by the client, include i nclude construction of a new year 7 playground, extending existing netball courts, single storey sports store to existing sports hall, works to existing access road and to provide additional car parking spaces and finally a renewal and adaption of existing surface water drainage system. This project is going to be pursued as part of a JCT form of Contract and the contract type is i s design and build. Our challenge is to come to a quality assured, cost effective efficient project completion as soon as possible whilst having mainly to cover the client’s requirements in order to satisfy the client as much as possible. Therefore, as of group B being the design and build contractors, it is required to produce any further or alternative contractor designs, to accommodate any changes which may improve the project in certain ways which can then be proposed to the client, whilst dealing with any problems arising in a professional manner. The project alternatives which are illustrated further in this section of the report will go as part of a range of conceptual designs which have bee been n considered for the client, should any alternatives be considered and used depending on client’s discretion di scretion with the project, these alternatives may also be used in conjunction towards future similar projects. Further in regard to Sustainability & Environmental Awareness Awareness,, the project must strive to attain exceptional performance in all areas, delivering high levels of efficiency with continuous improvement in safety, quality and environmental performance. With regard towards concern for the environment today is vital for future sustainability and must be at the heart of what is to be covered. Followed from this, the key is to recognise the immediate environmental impacts of the project and actively seek to reduce such impacts on the local environment and community through noise, dust and odour control procedures. Waste minimisation is also vital identifying opportunities such as re-using materials onsite to reduce the impacts of waste transportation offsite is recommended. Sustainable design inputs to use as conceptual or possibly for the project is a principle factor in any scheme. Some research on the input and recommendations from previous projects may be useful such as; innovative technologies, recycled materials, waste reduction, materials from renewable resources and renewable energy sources to develop a building that is as sustainable and environmentally friendly as possible achieving a very high BREEAM Rating, within the clients specifications and budget.

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Client’s current requirements & method of construction  As part of the clients current requirements so far far to complete the design and build contract contract for the two storey sixth form centre, group B will wi ll work to develop a 1200m2 steel frame building as the method of construction, this will feature a pitched roof, bespoke round-top windows and have a brick-built design to sympathetically match the school’s traditional masonry buildings. Alternatives  As a classification for client’s objectives, objectives, the key aspect is to have a project completed completed with good time, costs and quality and in the modern day of industry, advances in technology are being made with an emphasis on ‘greener’ alternatives to many of the materials we use in everyday life. ‘Green Building’ is a term used to describe the design and construction of a sustainable and eco-friendly structure. With Wi th regard towards materials for  example, the key aim to resource all materials for the Darrick Wood School would be to obtain materials from the aid of sustainable sources where possible and incorporate locally sourced materials such as local facing bricks, coppiced timber and the like. The reason why many clients are now open to considering such an alternative is because it lowers any negative impact we may have on the environment, makes the buildings healthier and most of all helps to keep a better control time tim e taken to complete the project with possible lower  costs. Therefore, several of these alternatives are illustrated below which alternatives may make a difference. The following will be considered as the alternatives which can possibly be used for the Darrick Woods school project: Input and recommendations inspired from previous projects St Mary's Island Health & Community Centre With reference to the St Mary's Island Health & Community Centre located in St Mary’s Island, Chatham, Kent; this was constructed previously in 2004 for the client SEEDA by Provian Construction. As a result, this project came in the top 4 at the Kent Design  Awards, 2005 in the ‘Public Buildings’ Buildings’ category. Therefore from this being a fact, it would be very influential for the client to go with some design features that were used with this project for the Darrick Woods School project alternatives. The total value of the project came to a reasonable amount of £1.58 million and commenced over 35 weeks to complete under the same contract as with the Darrick Woods School, being a JCT Design & Build Contract. St Mary’s Island Health & Community Centre at Chatham was primarily prim arily designed and built as a “sustainable”

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building. Furthermore, the features of this building may possibly be efficient to consider  and use as alternatives for the Darrick Wood School as the following may have been incorporated with the design including: Installation of solar energy collectors

These act as a pre-heater for hot water storage and with photo voltaic cells being additionally installed; this would assist in generating electricity during the day which would go towards the equivalent of 10% annual electrical usage. Any excess energy generated, when there is no load on the building’s energy supply, is fed back to the National Grid. Increased levels of insulation Followed from energy which being consumed to provide for heating for the Darrick Wood School, this would need to be preserved or even for the building itself to maintain m aintain a good U value, levels of insulation is ideal to increase in order to reduce levels of outgoing energy. Therefore, a main solution to this which is also used on the St Mary's project is having increased roof insulation, using extruded polystyrene to form a ‘warm roof’ achieving a U value of 0-12w/m² ºC. As researched, the use of additional thick extruded polystyrene insulation in conjunction with cavity walls, built from insulating block work, along with the use of ‘outsulation’ and thin-coat render systems goes towards achieving U values of 023w/m² ºC for the walls. Additionally being further researched, a U value of 0-15w/m² ºC for the floors was attained using insulating polystyrene blocks in a suspended T-Beam flooring system with structural concrete topping, additional insulation and floating recycled timber flooring over the top. All of these mentioned points illustrated from the aid of  research seem to be carefully and well thought through and would be very useful for the client, Darrick Woods School to apply, as there will be efficient U values being present, which leads to the decrease of the amount of money spent on more energy needed for the building from its causes of non- efficient insulation. Uses of timber for Glulam beams on portal frames  As an added feature to the St Mary's Island Island Health & Community Centre portal frame design, this included uses of timber from sustainable sources to incorporate Glulam beams as both a structurally and aesthetically pleasing element. Additionally in comparison towards the Darrick Wood School's steel portal frame & their connections, the timber portal frame would go towards possibly being a more efficient method of construction benefiting the client in various ways. Additionally as researched, timber portals are constructed using Glulam construction and stainless steel fixings. As much as using this method in comparison towards other methods of portal frames available (further explained in detail

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later) with all methods; cladding rails hold the portals together along with eaves and beams. As previously mentioned, the timber Glulam portal frames would benefit the client in having a more structural and aesthetically pleasing result which may be cheaper and easier to manage in comparison towards steel framed portals originally chosen to use. Sustainable & efficient materials With regard to the sustainable materials being used for the St Mary's Island Health & Community Centre, these included the use of having cedar and green oak cladding from the aid of fully sustainable sources in lieu of steel cladding or brick and block facings and ‘green’ material alternatives such as rubber flooring in lieu of Vinyl’s, aluminium/timber  composite windows and steel gutter systems which went towards replacing plastics. With some of these ideas used as an alternative for such as replacing the Darrick Wood School's PVCu plastic guttering systems such as the waste pipes and rainwater goods with steel. This would primarily be more efficient to the client in terms of having a more reliable guttering system against having less cracks, breakages and leaks with steel pipes in comparison towards deploying PVCu plastics pipes installed for the guttering as a result.  An image to reveal the end result in how the St St Mary's Island Health & Community Centre looked as part of the end result is illustrated below which speaks for itself in being very structurally supported aesthetically pleasing: Innovation Centre Hastings With regard towards another project being sustainably built is the Innovation Centre Hastings being constructed and completed in 2006. The client of this project is SeaSpace and this is located in Hastings, Sussex which had a total reasonable value of £3.5 million.  Again in terms of the type of contract used is the same same contract used for the Darrick Wood Wood School, being a JCT Design & Build form of contract. This project was constructed on a sloping site, to make best use of the sloping site Provian Construction built the centre so that the front of the building features two floors whilst the back has three. The facility provides 1,600sqm of office space & 765sqm of workshops for  up to 70 firms. With regards towards further similarities of this project in comparison towards the Darrick Wood School, both projects incorporate steel-framed methods of  construction. Flexible, sustainable design and structure The difference with this project in comparison towards the Darrick Wood School project is that the Innovation Centre Hastings features natural ventilation, rain screen cladding as

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well as locally coppiced sweet chestnut cladding. Therefore from these features and its flexible, sustainable design the structure achieved a ‘very ‘ very good’ BREEAM rating making it one of the most environmentally friendly buildings of its kind in the region. Therefore looking at this fact, it would be inspirational for the client to go towards having using a more sustainable range of materials mainly being timber and having the use of natural ventilation. As a backup towards why a better choice in materials, more in particular, materials used for this project, the choice of the rain screen cladding as well as locally l ocally coppiced sweet chestnut cladding being merged with the steel framed structure counts towards being more aesthetically pleasing rather than having a brick design which looks no different in comparison with other typical designs. Additionally the client; Clive Taylor, Regeneration Manager, SeaSpace stated "We have been impressed by the commitment  you and your team have shown to delivering the project to the objectives set out by Sea Space". Therefore from this the methods used for this project going towards the Darrick Wood School client may be pleased and satisfied as a result.  An image to reveal the end result in how the Innovation Innovation Centre Hastings looked looked as an end result is illustrated below which speaks for itself in being structurally supported and aesthetically pleasing:

Dulwich Preparatory School This spectacular project is located in Cranbrook, Kent; whilst the clients were the Governors of the Dulwich Preparatory School who covered a project which come to a reasonable value of £4 million under a JCT form of contract. The overall scheme to this project was to design and replace the lower school's old timber framed classrooms with a substantial new school building, hall and 'learner' swimming pool. Conversion of the existing school buildings into staff accommodation is planned for the future.

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 As a result to this project, successfully completed completed work was pursued to dramatically dramatically improve teaching and ancillary accommodation at Dulwich Preparatory School's lower  l ower  school campus at Cranbrook in Kent. The design to this project may inspire the Darrick Wood School client to go with similar features that were procured along with this thi s project. The following illustrates the works that were covered that may be good alternatives for the Darrick Wood School client adopted from the design of this project includes: Striking entrance design overlooking an aesthetically pleasing view  A key design element to this project project which can possibly be implemente implemented d with the Darrick Wood School is the striking stri king entrance design, whilst glazed windows on columns create a focal point clearly visible from fr om the road through newly aesthetic pleasing landscaped area. Eco friendly roof lights, natural ventilation & installations of a wood-chip boiler  The eco-friendly school features roof lights to maximise daylight and natural ventilation and as a sustainable method of providing low environmental impact energy, which would be very essential for the Darrick Wood School Client to consider is a wood-chip boiler was installed to provide all lower school's hot water as well as heating a whole swimming pool.  An image to reveal the end result in how the Dulwich Dulwich Preparatory School looked looked as part of  the end result is illustrated below:

Phoenix Community Primary School This project located in Ashford, Kent by the clients being the Kent County Council was completed in 2008. The total value of the project come to a reasonable value of £3 million under a JCT SBC 2005 (Rev 1 2007) form of contract.

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The reason being in why the client of the Darrick Wood School may possibly consider  pursuing something similar to this project in particular is due to its i ts design as it recently achieved awards for the Ashford Borough Council Design & Construction Awards 'Best Educational Building' Winner 2010. The Phoenix Community School in Ashford was traditionally constructed as an award winning single storey primary school and children's centre. The works involved the demolition of the existing junior school replacing the previous two sites to bring the school together under one roof. The project involved temporary accommodation of the existing school during demolition and construction of the new school. The feature of this project in which may inspire the Darrick Wood School client to pursue is followed below. Breaking the mould in educational design with naturally lit & ventilated building The features covered to provide for such an influential design, vertical timber cladding and is shaped in a curve that protectively embraces its entrance, forming a central courtyard for waiting parents and outdoor activities. Facilities include a reception class, six naturally lit and ventilated classrooms, an IT suite, teacher's pods, hall, kitchen, administration areas, sanitary accommodation, family rooms and a community children's centre and library.  An image to reveal the beautifully constructed constructed end result in how the Phoenix Phoenix Community Primary School looked as part of the end result is illustrated below:

Alternative portal frames With regards to the steel portal frame being chosen for the Darrick Wood School, this is a reasonable method of construction for the project however there are alternative options in regards to the type of materials being used for it. This further going to be explained in detail as previously mentioned. Surinder Singh

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Overall a portal frame is in the shape of a portal and is a structural frame that forms the building with lightweight cladding to provide weather resistance and to create an enclosure. Additionally, these offer a large open span and a large floor space. The portal will consist typically of having a low pitched roof member that is attached to a column at either end. Further from this going into the various ranges of materials available to be used along with portal frames, these can be constructed from as previously mentioned, timber  otherwise the other material includes using reinforced concrete as much as what is currently being used for the Darrick Wood School, being steel. Concrete portal frames are generally pre-coasted within a factory environment that ensures consistent quality. They are then assembled on site, like the currently chosen steel frame would be from using a mobile crane. With regards to the timber portal frames, this has been previously mentioned earlier with it being constructed from Glulam construction and stainless steel fixings. As additionally being mentioned earlier also, all three material types of portal frames would proceed with the aid of cladding rails holding the portals together along with eaves and beams. With the choice of having a portal frame being used for the Darrick Wood School, this is good because they have the following advantages including: • Large spans can be achieved • Speedily erected • Factory-produced quality • Easily extended and adapted • Good height-to strength ratio • Enable lighter foundations than traditional construction or brick and block previously mentioned) •  Aesthetic when timber used (as previously • Enables recycling when the building comes to the end of its life Overall however, with the choice of the Darrick Wood School possibly proceeding with the steel framed portal frame, this is not a bad feature due to generally, modern portal frames are constructed from steelwork and as previously mentioned, this enables a typical high strength-to-weight ratio, which gives a large economical span, this mainly the case with steel frame portal frames. However there are some disadvantages to using the steel portal frame as much as using any other of the previously mentioned types of portal frames, these disadvantages include: • Some form of coating to prevent rust is required • Fire protection coating is required • Expensive to bend m aintained • External coatings have to be maintained

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Overall the other timber Glulam and reinforced concrete types would offer something similar if not a greater strength-to-weight ratio with providing a reasonable large economical span. With further detail in regard for concrete portal frames, concrete forms of construction are generally divided into two forms and as previously acknowledged, these are: • In situ • Pre-cast In situ concrete frames consisting of beams and columns require some form of formwork in which mixed concrete is poured and held until it has set and attained enough strength to have the formwork shuttering removed. Pre-cast concrete is similar to that previously described and may require some of the beam-to-column connections to be cast on site or  bolted to form a rigid structure. The advantages of concrete frames include: • In-built fire protection • Can be moulded into any shape • High strength in compression • Do not require a secondary finish • Faster connection period using pre-cast • Variety of surface finishes can be achieved The disadvantages or limitations offered from the aid of concrete frames include: • Support is initially required • Cranes are required • Presence of poor strengths on tension • Require highly skilled workforce to assemble   Other than looking at some of the disadvantages above offered from the use of having concrete frames being a possible method of frames being used for the Darrick Wood School, overall, whilst referring to some of the interesting advantages and features that concrete portal frames have to offer from the above, if the option of steel frame portals are to be further pursued by the discretion of the client of the Darrick Wood School, the steel frame portal will consist of beams and columns and may be composite in design, which means they can contain concrete floors and steel supporting beams, that is a mixture of  two technologies, therefore there’s an alternative on "best of both worlds" being present

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which would be a good option for the client to procure depending on what is more efficiently feasible and easier for them. Alternative roofs With regard to currently required for the roof of the Darrick Wood School, a pitched roof  has been chosen to pursue. As much as going ahead with the pitched roofs, several alternatives may be possible to use along with the choice of the Darrick Wood School, these are further illustrated below whilst being identified where possible plus and negatives will be illustrated. These are additionally going to be illustrated with firstly fi rstly covering the choice of using pitched roofs along with the project and what it may offer. Pitched roofs With pursuing to this roof, these can take much form including flat, mono-pitch, m ono-pitch, gabled, hipped, or accommodating multiple pitches and features. As researched, traditionally, these roofs have been built by carpenters on site using large sections of timber with features being created as work proceeds. To come to an acknowledgement on how the roof arrangements will take place for the Darrick Wood School, more recently, the use of  trussed rafters has meant that the roof is would be crafted using a series of manufactured triangles of frames to create the roof in pieces that are then assembled in situ. The use of  trussed rafters however being used on the Darrick Wood School will offer and result in possible improvements in the standard of workmanship and thermal performance which is basically leading the Darrick Wood School roof itself having the ability of a material to retain heat within the structure. Therefore this may be a good sustainable aspect of the pitched roof being used. Additionally the other advantages this type of roof would offer to the Darrick Wood School is having the use of smaller, more economic sections of timber  will enable roofing made more affordable and feasible for the client. Flat roofs With regard in using this type of roof for the Darrick Wood School, these can effectively count as being a cheaper option to use in comparison towards using pitched roofs which have been previously mentioned above. However these types of roofs may not be suitable for the Darrick Wood School due to flat roofs which by risk ri sk would be constructed incorrectly for any type of reason, will suffer from the result of a great deal of  condensation, therefore the cheapness of the flat roof construction will possibly be better  for the use on smaller contracts, such as small extensions to domestic buildings. Furthermore however, if the flat roof alternative was to be pursued by the client of the Darrick Wood School due to its cheapness, to avoid any problems occurring, the use of 

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large sheet materials or rolled aluminium profiled sheeting with correctly positioned vapour  checks will be more successful for the Darrick Wood School. Additionally as previously acknowledged, the performing of vapour checks with the Darrick Wood School would involve impermeable barriers or membranes used to prevent moisture passing through the of the Darrick Wood School's structure.

Short-span and medium-span roofs With the result of using this type of roof, again this type of advantages in being good in relation towards cheaper costs being included which would benefit the Darrick Wood School client with this type of roof as much as the use of deploying flat roofs previously being mentioned above. If this type of roof is possibly chosen to go with for example, usually short-span roofs can be made from timber, whereas longer-span requirements will need stronger members made from either steel or concrete. Overall with regards for the client to choose the best roof possible for the Darrick Wood School, the client will need to be aware of a few precautions. The span of the roof will be dependent on the rood loadings and the use of the building. Generally the client must be aware that the wider the span of the Darrick Wood School area, the deeper the beams are required in order to carry the load. Alternative forms of construction Traditional form of construction Traditionally built buildings are labour intensive and require most of their construction to be built on site. If the Darrick Wood School goes with this option, this will lead into making the process of construction expensive and difficult to monitor for quality control. This is a major  disadvantage for the Darrick Wood School as there will need to be various tradespeople being required to work onsite such as ground working crew, a bricklaying gang, several  joiners or carpenters, roof tilers/slaters, plasterers and then then the services engineers, engineers, such as plumbers and electricians to fit out the interior services. The project will also require materials being delivered to site which then have to be stored ready for use.

Prefabrication form of construction  As a result from previous acknowledgements, acknowledgements, prefabrication involve involves s manufacturing and constructing components such as toilets facilities and components and window frames fr ames in a factory. The components are then taken to the site where they are assembled. Using

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prefabricated components as much as defining in further detail relating to the Darrick Wood School project, will reduce time spent onsite in comparison towards applying the traditional method of constructing everything onsite from scratch. Furthermore, prefabrication components improve quality of the finished fini shed project and speeds work onsite.  As part of a modern alternative from traditional forms of construction, construction, the Darrick Wood School group B contractors as much as the client are most likely to go with this option as a form of construction. In recent times, there has been a shift towards prefabrication of  single or multiple components. As a result to the performance of the construction for the Darrick Wood School, this form of construction will increase the speed of erection onsite for the completed units and will also result in improved performance based on the high quality of materials and workmanship. A high level of control can be maintained in workshop conditions and the completed components taken to site for assembly.  As much as the Darrick Wood Wood School client and the group B contra contractors ctors going with the going along with prefabrication forms of construction, acknowledgement is to be made that the success of prefabrication within the construction process depends on the following: A well designed construction site layout l ayout - This typically will rely on the construction manager having detailed knowledge of the operations and the layout of the construction site to ensure that each component is integrated at the appropriate time. Correct sequencing of the construction works - This will rely on the designer and construction site manager working together to ensure that the correct plant and components are delivered to the site in the right sequence. Use of prefabricated components wherever possible - careful consideration of the structure and the design brief will enable the designer to identify all components of the Darrick Wood School project are suitable for prefabrication. The construction site manager  should be consulted as they are also likely to have detailed information on the practicalities of delivering large items to the site and whether it will be feasible to assemble and install large items on site. Use of plant at all stages of construction - wherever possible, skilled craftspersons should use machinery to help them assemble and install components correctly. The reduction or elimination of as much physical labour as possible is a key feature in improving the economic viability of prefabrication the Darrick Wood School project. Advantages and disadvantages of using prefabrication form of construction

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If this form of construction is to be used with the Darrick Wood School project, the components such as door frames and many more are now frequently made offsite and will be taken to the Darrick Wood School site for installation and assembly rather than being built in situ. This prefabrication of components has not been restricted to non-load bearing elements, and for the Darrick Wood School where it most possibly will be pursued to be a steel frame building, standard forms of structural steel sections can be cut, bent and shaped to specifications, then taken to the Darrick Wood School site and placed on prepared slabs and linkages to assemble the building in sequence from the ground upwards.  As previously mentioned, while there there is expected to be significant improvement improvement with the standard of workmanship and the speed at which the Darrick Wood School project will be using prefabricated components can be built, there are some limitations to the use of  prefabricated elements that both the group B contractors and the Darrick Wood School client need to be aware of. These will include aspects such as all components not being likely to be built offsite and there will always be need for some minor alterations as work proceeds. This is especially true of instances where the design of the Darrick Wood School project would be agreed in advance. If any aspects of the Darrick Wood School design need to be changed for example, then it may be easier to make any alterations required onsite while work is taking place. However if this is the case with the Darrick Wood School project, the client will need to be informed as much as the group B contractors are able to contact and communicate changes to the workshops and other  subcontractors can these changes be made if the project is to rely on prefabricated elements. Furthermore however, if the Darrick Wood School project is involved with the whole building being completely prefabricated that is, taken to the site and fully assembled and lifted in position using a crane onto a prepared base, variations are possible, although care must be taken to ensure that the removal of or amendment to any component does not adversely affect the structural integrity of the building.

References Brett/Provian Construction. 2011. Brett/Provian Construction. [ONLINE] Available at: http://www.brett.co.uk/provian_construction/about_construction.htm. http://www.brett.co.uk/provian_con struction/about_construction.htm. [Accessed 17 November 2011].

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Topliss; Hurst; Skarratt, S.T; M.H; G.S, 2007. Construction Building Services Engineering & Civil Engineering. 1st ed. 2007: Heinemann.

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