Plymouth University. BREEAM Excellent rating. STA MEMBER Stewart Milne Timber Systems CLIENT. Plymouth University. MAIN CONTRACTOR BAM Construction

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1 Plymouth University BREEAM Excellent rating In February 2011, work started on Plymouth University s first on-campus combined student and medical staff accommodation at the Knowledge Spa, Royal Cornwall Hospital. The bespoke 8.5 million sustainable development will benefit Cornwall s future doctors, dentists and other frontline health professionals at the county s premier health education hub. With Plymouth University s award winning reputation for sustainability, the 232 bed development comprises seven blocks of four storey units, arranged as a series of self contained four and five bedroom flats. The blocks are arranged informally around a central landscaped area, with materials such as timber frame, Siberian Larch rain screen cladding and a low pitched standing seam zinc roof selected to complement the woodland surroundings and to create an entity distinct from that of the hospital. Well experienced in completing large scale developments to meet BREEAM Excellent and Outstanding levels, Stewart Milne Timber Systems was selected to provide the timber build system. Working with main contractor BAM Construction, Stewart Milne Timber Systems used a fabric-first approach in order to meet the required U-value of 0.2W/m 2 K, by providing a semi closed pre-insulated panel system. STA MEMBER Stewart Milne Timber Systems CLIENT Plymouth University MAIN CONTRACTOR BAM Construction ARCHITECT Burwell Deakins & Grainge Architects ENGINEER Hydrock TECHNOLOGY Semi-Closed Panel Timber Frame

2 Key Drivers Achieving BREEAM Excellent rating Quality assured off-site manufacture significantly simplifies construction, resulting in less on-site waste (as much as 20-40% less) when compared with other construction methods. Timber Frame promotes greater efficiency and supply chain integration and brings predictability and greater control to the construction process. The timber used is naturally renewable and responsibly sourced from managed forests - with full Chain of Custody. Even taking into account transportation, it is carbon neutral. Timber also reduces the embodied carbon dioxide of a building when used instead of more energy intensive materials. This can be up to six times lower than masonry. For every cubic metre of wood used instead of other building materials, 0.8 tonne of CO ², is saved from the atmosphere - with the average timber frame home saving around four tonnes. Building in timber frame makes it easy to achieve a high performance building fabric by maximising thermal performance and minimising air leakage. This Fabric First approach is a low risk, cost-effective way to achieve higher levels of BREEAM 1. Sustainable building was fundamental to the project, and a key aim was to achieve BREEAM Excellent rating. The development was driven by the desire to avoid an institutional feel or appearance. Note 1 - BREEAM - Building Research Establishment Environmental Assessment Method is the world s leading assessment method and rating system for buildings. BREEAM sets the standard for best practice in sustainable building design, construction and operation. It encourages designers, clients and others to think about low carbon and low impact design, minimising the energy demands created by a building before considering energy efficiency and low carbon technologies. 2

3 Business Perspective Partnership was crucial and Stewart Milne Timber Systems (SMTS) worked closely with the team from a very early stage. SMTS engaged with the design team from the outset and were in continuous dialogue with BAM Construction between December 2011 and April 2012 to ensure a design freeze the last stage at which a design can be altered - in line with the overall programme timetable. SMTS believe that such close working and attention to detail at the front end of the project is time well spent and ensures that the project runs smoothly thereafter. The similarity of the block layouts led to the drawing approval process and co-ordination of the buildings becoming very slick as the project progressed. Key Design Drivers Creating a sense of home is one of the key concepts that drove the design of the residences for the University of Plymouth at Truro. Set amongst the existing landscape, the residences will be both a place for engagement and of tranquillity. A cluster of simple and robust forms create a degree of privacy while at the same time encouraging a sense of community and a usable external environment. Within each house, dual aspect living arrangements allow for well-lit spaces, with communal areas promoting interactivity and communication. By repeating the building forms and using a sustainable timber construction the scheme implements environmental and low energy strategies. 3

4 Design Concept/Structural Philosophy Timber frame projects were relatively new to this division of BAM Construction, so partnership was crucial. Stewart Milne Timber Systems worked closely with the team from an early stage, engaging with the design team from the start and were in continuous dialogue with BAM Construction to ensure a final design in line with the overall programme timetable. This is time well spent and ensures that the project runs smoothly thereafter. 4

5 Onsite Story With speed of build a vital aspect of the project, Stewart Milne Timber Systems utilised offsite construction to achieve the necessary requirements, allowing the timber systems for all seven blocks to be completed in just 16 weeks. The pre-insulated panel build system and a pre-fabricated cassette floor helped to meet the tight build programme. Stewart Milne Timber Systems also fitted an acoustic floor system and the stairs for the project, which streamlined the supply chain process and helped to further speed up the construction process. For developers, it is imperative that student accommodation projects are delivered on schedule because missing term deadlines could have major implications. Speed and predictability of build are essential and due to offsite construction, timber frame is one of the best materials for delivering large scale projects fast and effectively. 5

6 Cost, size and type of system VALUE: 8.5m bespoke medical student residential accommodation SIZE: 232 units PROJECT DURATION: 16 week timber frame erect programme A semi closed pre-insulated panel has been specified to provide the required U- value of 0.21 W/m 2 K for the walls. The specification was a reflective breather membrane on to a 9mm OSB racking board, fixed to a 140mm panel with 120mm urethane insulation factory fitted into panels. A pre-fabricated cassette floor was also used to achieve tight build programme on site. Pre-formed trussed rafters were supplied to form the pitched roofs, to assist the speed of build and to accommodate the plant loadings of equipment that was placed in the roof void as well as solar panelling to all roofs. Building Performance The building had to perform to a standard of BREEAM Excellent. Thermal performance was a U-value of 0.21 W/m 2 K for the walls and an air tightness 4/5 ACH was achieved as an air leakage factor by using a pre-fitted air barrier at the floor level (to continue air barriers from the walls to the levels above). Co-ordination of building services was undertaken at an early stage and SMTS were able to design pre-formed service holes and voids into the internal and external walls to assist the follow on trades. 6

7 Project Testimonial One of the key factors in Stewart Milne Timber Systems being selected to provide the timber system solution was that they had experience of working on large scale projects to meet BREEAM Excellent rating. Along with the company s excellent reputation in the industry and the cost benefits they could provide through their one stop shop approach, Stewart Milne Timber Systems was the ideal choice for this project. Dave Roper, Project Manager, BAM Construction 7

8 Falcon House Curbridge Business Park Downs Road Witney Oxon OX29 7WJ t: e: DCCS-04/2014 Head office Structural Timber Association The e-centre Cooperage Way Alloa FK10 3LP t: f: