Green Orchards is a new build private house on a rural site in the West country, constructed to the highest standards of energy efficiency.
The client brief was for a building which would be zero carbon with respect to heating, lighting and ventilation. As the building is partially earth sheltered, cutting into the natural topography, a hybrid construction system was developed to suit the differing requirements of the upper and lower floors. Various construction options were considered comprising a number of heavyweight and lightweight building systems, judging these options against budget, buildability and energy performance. The final solution agreed comprised a reinforced concrete lower storey with an upper floor of timber frame construction.
The design focused on providing a clear strategy for insulation and air tightness. Where it was not possible to design out thermal bridges in the concrete, careful use was made of cast in thermal breaks. In some locations bespoke details were designed by Fluid as no proprietary product was available. The ground floor concrete “box€ was heavily insulated externally and left substantially exposed internally as coupled thermal mass. On the upper floor jumbo studs 250mm deep and timber fibre board were used for walling, with 400mm deep I-joists for the roof. Both were insulated with blown in Warmcel cellulose insulation, avoiding high embodied energy materials.