Mountains & Opening House / EASTERN Design Office

© Koichi Torimura

Architects: EASTERN Design Office
Location: Takarazuka, Hyogo, Japan
Client: American Club International Co, ltd
Structural Engineering: Hojo Structure Research Institute
Constructor: Fukasaka Co., Ltd
Site area: 711.46 sqm
Total floor area: 361.84 sqm
Project Year: 2009
Photographs: Koichi Torimura


This building is a design room for a Japanese sneaker brand as well as a residential house. The site is in Takarazuka-city of Hyogo Prfecture. It is located in an exclusive residential district that commands an entire view of the Osaka Plain. The architecture is built on the slope of a hill with an elevation of 330 meters. The level difference of the site is 8 meters.

sections 01

Taking advantage of the slope, one of the characteristics of this site, an architecture which suits the desires of two persons is built.
A. To be warmed up. A lower floor, a house, invisible in a mountain.

1. The site has an 8 meter difference in height. 8 meters is higher than a two-story building. The lower floor is in the ground of the slanted site. It is invisible from the upper road.
2. There is a bedrock layer 1.5 meters beneath the ground surface. It is so hard that even a shovel car could not crush it. Dig to the bedrock and the foundation is supported by this bedrock.
3. Build two mounds using the soil dug. Insert a residence between these two mounds.
4. Built on “a new topography-mountain”, all parts of the building are close to the earth. The mountains are designed to emphasize the slope.

© Koichi Torimura

An exclusive residential area on a hill features a good commanding view as its sales point. Development of this kind of community is planned in a similar way with no individuality. We consider this phenomenon as “a loss of topography”. We have dreamed of a mountain whose slope was scraped away. The lost mountain is designed into this architecture.
Architecture is not built on a site where the slope is flattened. By contrary the angle of the slope is increased, which results in two mounds. Between these two mounds a living space is built, and the upper story floating on these two mounds is a design room.

© Koichi Torimura

B. Flying. An upper floor, a design room

1. Observe the Gulf of Osaka, high-rise buildings, Kobe port, Kansai Airport, Itami Airport, and shadowy blue mountains.
2. The land originally slanted at an angle of 18 degrees. Mounds are built there to let the slope undulate.
3. These mountain waves are topography where no previous topography existed. The upper floor was designed to float on these mountain waves.
4. We have designed the form which passes over the waves. Is it a dream of a long-distance ship going over high waves or is it a dragon?

© Koichi Torimura

The dream of this architecture is like a voyage setting out.
An 18 meter-long terrace. The sea and a range of mountains 60 kilometers away can be observed. When standing on this terrace, rows of other houses in this area are out of sight. This is the way we have arranged this architecture and its openings.
You can get a sense that your body is slightly floating. It is our intention to give the sense of being on a deck of ships, but not in the house. The design room on the upper floor of this architecture is a ship.

first floor plan

The plan is designed in L-shape. The edge protruding greatly from the slope is an opening that swallows the outside. Straight eaves run amidst the curvilinear forms of the topography. The eaves project in a powerful manner not to be beaten by the inherent force of the topography. They are thin, thick, short, long and carved.
To be protected by the house, yet at the same time have the feeling of flying away. Making two extremes into one. This is realized in the architecture in the corresponding forms of the upper and lower floors.

© Koichi Torimura

It is a cave and also a nautical form.
It is flying away, yet it is anchored.
It is drifting, yet it is homely.
It is sky, and it is Earth. It is far, yet it is near.
1.5 meters beneath the ground surface is hard bedrock. The foundation is raised on this bedrock. For this, the excavated earth was used and the red curving line was designed to achieve this. In other words, by heaping up the excavated soil, a new undulating mountainous topography is built. The lower floor is built under the mountain.
The form which runs over the mountains is the upper floor. The corresponding upper and lower floors are made into one form.

sections 02

This is a slope when architecture is erased. The architecture of the “house” is a “mountain.” The plan for this slope is to shape the mountain structurally, but that goal was to let people feel the uninterrupted flow of the curves that define the mountain. Let the people have a sense of closeness to the wave-like mountain. A small change to the curve will lead to a loss of balance, affecting the way openings should be designed, the mountain, and the entire architecture will also have to be change its form. However at this moment not even one person felt unnatural when standing on this undulating slop.
A person standing on a slope. A person crouching on a slope. A person flying off a slope. Only on a slope can people look back on the road they’ve climbed and, also can look at the way they will go from now on. It can be called a visional place that inspires people.