Resembling the deck of a ship, the sloping roof over this house near Tokyo accommodates various functions – sitting, cooking, dining, showering and sunbathing. The single-storey building has a strict layout with rooms divided from the living area by sliding partitions. A skylight in every room allows ladder access to the roof deck. The south face of the house is fully glazed, affording a view to a small garden, whereas the street front is virtually closed. The roof structure consists of a grid of 105/105 mm timber beams. With a double layer of plywood on both faces, it acts as a rigid diaphragm, which allowed the depth to be kept to a minimum and ensured an elegant appearance – without balustrades.