The house, which is square in plan, is subdivided by a tartan grid in a 600mm module (the width of three velux standard windows). Servant spaces are restricted to the central cruciform area. The houses have pyramidal roofs which are independent of internal structural members. They are supported by two-storey central laminated-timber post-and-beam structures and the external walls. Roof space may be inhabited or left vacant, and rooflights fitted where required. The relatively small external wall area makes the buildings energy efficient, and the southern side has a double-height glazed space to make use of passive solar gain.