This is the project that the client returned to the birthplace after the retirement and rebuilt an old house. He requested sunny one-storied house with good ventilation. But there was a problem that an erstwhile quiet green residential area was changed into densely built-up area, and moreover neighbor's concrete block wall surrounded his flagpole shape site. And there was a sense of being oppressed.So we tried the design “Shakuhei”(=Borrowed wall) to turn this bad condition to the advantage. Incorporating beautiful landscape is usual method at "Shakkei", but this project "Shakuhei" is a trial to incorporating neighbor's ordinary concrete block wall. Therefore, we dared to make the house with a concrete block wall. Firstly, we cut this site into pieces on a cross with concrete block wall. Secondly, we put one roof over the top of the wall.As a result, in all rooms we obtained scenery that our wall and neighbor's wall are seen at the same time. In a word, it is felt that neighbors' walls are own walls. And we feel this house compact but large, because each rooms have a garden. Further, we got a sense of unity and a reflection effect by painting neighbor's wall white with their consent. However, we want not only to borrow the wall from neighbors but also to build the relation of win-win. So that, we secured the neighbor's sunny space with good breeze by making the flat roof terrace and painting it white.Fill-up concrete block structure (=for retaining walls) makes it possible to secure horizontal force by even if it is a straight joint. We planned efficient air conditioning in consideration of loop space. The air-conditioner blows air into air loop duct after taking return air from the center of the house. The air inlets are familiar screen blocks in a Japanese town. And the air outlets are simple holes but manual regulation of air volume is possible.