28 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 1 Showell Court, Wolverhampton Contributed by Paul O’Driscoll Wates Living Space paul.odriscoll@wates.co.uk Name of project: Showell Court Town or city: Wolverhampton Brief description: 64 apartment extracare home with communal facilities including sensory garden. Total cost: £7.2m Average cost per unit: £114,286 Principal partners: Wates (constructor), Pozzoni (the architect), DWP (services engineer) Stewart & Harris (structural engineer) Hemsec (the system provider) and Accord Housing Association (client). Completed: October 2009 Length of time to build: 60 weeks (further time would have been saved but for tolerance problems with precast concrete planks) Estimated time using traditional methods (from start on site ): 70 weeks Briefl y describe the construction method The offsite method involved the use of structurally insulated panels (SIPs) and precast concrete fl oor planks and stairs, externally clad in traditional brick work and look-alike copper cladding with a structural steel transfer slab with communal facilities. Erected using forklift. Why was this method chosen? Due to limited design available at tender we needed to delay the start on site to allow a fully co-ordinated scheme to be provided whilst still maintaining the critical end date for Accord. Changing from traditional to SIPs with precast concrete (PCC) planks allowed more time at the front end to complete the design and Accord’s brief. The use of PCC planks and SIPs also avoided the issues of overheating and excessive cooling plant often required with standard timber frame. Were there any additional/ unusual approvals needed and what were they? The SIPs and precast concrete fl oor were unusual and therefore an engineer was used to ensure that this composite system worked structurally. The engineer worked closely with the SIPs manufacturer and the pre-cast plank company on behalf of Wates to ensure this innovative structural solution met current regulations. We also needed to agree a new suite of bespoke Robust Details with Building Control and NHBC as this was the fi rst time this system had been used for residential developments. How did costs compare with traditional methods? Slightly more expensive for construction materials, however the preliminaries saving covered this extra cost. Would you use this method again? Yes What are your reasons? Speed and ease of build and because it provides a higher thermal mass which reduces overheating. Other comments on offsite manufacture for housing construction? The offsite components were a good quality product, manufactured in a quality environment. We still suffered design issues and perhaps if the use of BIM was employed, these design/sizing issues may have been prevented.
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