Photo: Hiroyuki Hirai
This long rectangular site (9 meters by 19 meters), with its short side fronting on the road, has an elevated ground level of 2 meters. There is a large cherry tree which designated to be preserved at the south corner of the site. The work space for the dentist is located in the basement level and the living quarters are distributed on the first and the second floors. The rectangular floor plan (7.6 meters by 18 meters) is divided lengthwise into two parts-the southern half to be used as exterior space and the other half as interior space-and all the rooms are aligned in the longitudinal direction to share the view of cherry tree with every room. The client wanted reinforced concrete construction for his house, but since the poor ground condition would have required pile foundations, and in view of the resulting issues of cost and the limited construction period, this type of construction could not be used. The building was made as light as possible using the minimum amount of reinforced concrete construction and with the floors construction in wood. The concrete portions of the structure include the two parallel walls which define the front and rear sides of the house (18 meters apart) and the circular core structure-with laminated wood joints spanning between these concrete elements. With the minimum use of solid walls, the sense of spatial openness is optimized by the use of glazed walls. A 3-story-high ivy-covered screen which defines the southern boundary ensures the required privacy and allows ventilation and filtered natural light. On the north facade the glazed openings are fitted with hollow polycarbonate panels filled with granulated styrofoam.