Having secured the commission through a limited competition, the client's brief was to design a passively ventilated headquarters building for the Aldwyck Housing Association. Working closely with specialist engineers, Rybka Battle, we designed a building which provides 3,500m² of office accommodation within the 12m wide open floor plans, either side of a fully glazed atrium. The principle of the development is to allow cool night air to infiltrate through the high level windows and cool the exposed coffered concrete soffits. This concrete mass acts as a cooling sink convecting cool air into the spaces below during the day. Warm air is also drawn across the floor plates to the central atrium and expelled at high level through the fully ventilated wind towers.