Japan Sustainable Building Database

Project Outline

This is a house for a family of five (a husband, wife, two children, and a grandfather) . The site is located in a new residential area within an academic town in a suburb of Kitakyushu. A long dirt floor space, which is open to the ceiling of the second floor, is laid from the road in front of the north side of the house to the vacant lot on the south side. Rooms are placed on the east and west sides of this dirt floor. The "dirt floor" has two functions. One is a three dimensional "opening" connecting the empty lot on the south side and the road on the north side and an alley-like space passing through the house. It lies between the bright east-side room area and the west-side area, including the water section and the bedrooms with a relatively small frontage. It separates the areas comfortably. The family members must go through this space whenever they move for daily activities (to the water section, for example) and go to their own rooms. The other function is a buffer in the indoor environment. In winter, it collects and stores heat (like a greenhouse) when the solar irradiance is high, or serves as a buffer between the inside and the outside when the solar irradiance is low. In summer and the intermediate seasons, the dirt floor facilitates ventilation and drafts and performs passive cooling using its thermal capacity.
Such a passive approach is used to realize a comfortable indoor environment with minimum reliance on air conditioning. The family members feel weather and environmental changes day by day and minute by minute and adjust the room temperature and solar radiation accordingly. As for architectural aspects, fittings, which can be opened and closed according to the mode, are provided in the wall of the dirt floor (the boundary between it and the rooms) for passive and active control of solar radiation performance. Compared with the airtightness of the exterior wall, that of the walls of the dirt floor and the living space is much lower. These walls are just like a "breathing film" capable of controlling air freely.

Basic Information

[CASBEE rank]	S  ()
[CASBEE tool used]	CASBEE for Home (Detached House) (2007 edition)
[Location]	Kitakyushu, Fukuoka Prefecture
[Completion date]	November,2007
[Site area]	225 m2
[Total floor area]	164 m2
[Structure]	Wooden architecture
[Floors]	2 floors above ground
[Owner]	Yasuyuki Shiraishi
[Designer]	Inter-Space Architects/Manabu Okochi + Momoyo Goda (URL: http://www.inter-space.co.jp/)
[Environmental planning adviser]	Shiraishi Laboratory, The University of Kitakyushu
[Contractor]	Imamura Komuten

Information for visitors

Not permitted

Publication

N/A

Awards

• 3rd Sustainable Housing Awards, IBEC Chairperson's Prize (Institute for Building Environment and Energy Conservation, 2009)