- Design Team : Izumi Kozasa, Naoko Okumura
- Supervision : IN STUDIO, Izumi Kozasa, Naoko Okumura
- Structural Design & Supervision : Studio Stem, Mikio Nakajima
- City : Yokohama
- Country : Japan
Text description provided by the architects. The house stands almost at the top of a hilly residential area 10 minutes by train from Yokohama. Originally developed in the 1950s as Futamatagawa New Town, the land is laid out along the topography in regular rows of similarly sized residential lots. In addition to being a first-class low-rise residential area, the land is subject to strict diagonal restrictions starting at 5m on the north side. These land divisions and regulations result in a hilly area covered with small detached houses. This is a common hilly residential area that is repeated in other parts of Japan.
However, the method of construction of retaining walls to cope with the difference in height, the construction of front gardens and garages, and the external shape and materials of the houses are left to the owners of each lot. In the new town, there is a strong sense of uniformity and a sense of the power of the planners, but here there is a peaceful atmosphere in which you can feel the lives of the residents.
A couple with a small child decided to buy this land and build a house on it. The budget for the building was 19.5 million yen including tax. As a designer, I felt that the new house should be part of this townscape, and being aware of the family's budget, it seemed best to use a wooden house with two floors as a basis, and to make some changes to get the best out of the hillside. We wanted to pick up the advantages of a space that is completely wrapped in the hillside and looks up to the sky.
The first step was to create a house-shaped volume at the full limit of diagonal lines, with the facade set at an angle to avoid the existing retaining wall and external staircase. The terrace overlooks the valley of the hill and shelters the garden and the entrance. The view of the hillside from the terrace, with its houses and trees, is a reflection of the place where we live, while the sheltered garden is a continuation of the hillside ground.
Secondly, the slab of the first floor was made thinner and raised as far as possible, suspended by wooden posts. This allows the first floor to be lifted higher and closer to the sky than the house opposite, which is on a lower level, and the ground floor to look up at the sky with a ceiling that is not so high that it is felt.
In addition, the windows are made full-height and the interior is made up of repeating strips of the wall. This allows skylight to reach the back of the ground floor from all directions, and intermittent views of the outside light allow the atmosphere of the outdoors to permeate the interior.
Finally, on the level between the first and first floors, a landing with a desk and a utility room are placed to mediate between the floors, contrasting the small scale of the landing with the large scale of the living room. The wooden ceiling in the living room and the slab in the earthen floor are extended both indoors and outdoors so that the interior and exterior enter into each other and extend out into the garden and the hillside. The result is a house with a pilotis-like ground floor leading from the slope of the hill and an observatory-like first floor overlooking the hill.
The design of this house was about a family's search for a house that would allow them to live in today's world, to feel free and rooted in the land, but also to find a type of house that would be repeatable due to the general nature of the land in a typical new town and the general nature of the budget, which is more like a built house than a luxury house. It was also a question of It is my hope that this project will become more widespread if it is possible to create a space for living in today's world through the transformation of a wooden duplex without special forms, plan types, or construction methods.