WOODLAND WONDER
CASE STUDY
CONSTRUCTION IN PROGRESS
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1 The Isoquick EPS foundation system wraps the entire raft foundation in insulation to eliminate any thermal bridges; 2 laying the 250mm reinforced concrete slab; 3 installing I-beams for the stick-built timber frame system; 4 Green Building Store Progression windows installed into the timber frame system; 5 airtightness detailing around windows; 6 external wall build-up includes a Siga Majvest façade membrane, a 50mm ventilation zone, and 2x20mm Douglas fir cladding.
28 | passivehouseplus.co.uk | issue 29
another Herefordshire-based passive house specialist, Mike Whitfield. In 2005, Whitfield was the main contractor for the Duchy of Cornwall on the conversion of two barns into Architype’s office, a project that won the 2007 RIBA sustainability award. He has completed around 15 passive houses over the last decade and is now working on a low energy building to mark Prince Charles’ 70th birthday. On the Fishleys development, Whitfield took charge of the build on site after Architype had completed the plans. He liaised with the engineer and spoke almost every day with Liz, who was working from home. Whitfield suggested all kinds of small details, such as an oak door with oak latches, which added to the beauty of the home, although in other matters, the couple preferred to find their own more cost-effective options. Groundworks lasted from summer 2015 until the end of the year and then building work began in January 2016. Whitfield’s team had the whole wooden frame watertight using I-beams in March despite torrential downpours and high winds at the beginning of February. The house was waterproof after eight weeks and the couple were able to move in by November 2016. All the framework was built on site as Whitfield prefers not to use prefabricated panels. “It’s more expensive to use prefabricated as long as you have the expertise to do it efficiently yourself. But if you have inexperienced carpenters on their first passive house, a factory product might be easier,” he says. “Another reason we prefer to build it ourselves is it gives us greater flexibility to start and finish when we want. In the time we were waiting for factory frames to arrive we might have built half of the structure. Having said that, as our workload