Wraxall House in Wiltshire was converted from a listed cart barn to provide living and working accommodation for two adults. The design exploits active and passive mechanisms to minimise energy consumption. The main facade, facing due south, maximises winter solar gain and controls summer gain using motorised external louvres; all glass is low-E coated. The stone superstructure has been restored and left exposed to exploit its high thermal mass. Additional heating is provided via a wood-burning stove and an oil-fired boiler supplying underfloor heating circuits. High levels of insulation have been achieved in the floor, roof and external walls. The structural engineer was Mark Lovell Design Engineers. Contract sum was £115,000.