Mountains & Opening House designed by Japanese studio EASTERN design office for a Japanese sneaker brand as well as a residential house. The house is located in Takarazuka-city of Hyogo Prfecture, Japan, having an entire view of the Osaka Plain. Due to its site condition, the house has been designed and developed based on the concept of being underground for getting warmth and flying like a bird.

Two mounds are made on a slope. This is the "topography" of the house. The house is "in the mountain." We have designed a floor to float on top of these mounds. There is an office inside it. It is a design room for the maker of a Japanese sneaker brand, Dragon Beard.

EASTERN design office

Mountains & Opening House, image courtesy EASTERN design office

Mountains & Opening House, image courtesy EASTERN design office

+ Project description courtesy of EASTERN design office

Mountain/Opening

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.

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 underground in the warmth of the earth.
B. To fly like a bird.

Mountains & Opening House, image courtesy EASTERN design office

A. To be warmed up. A lower floor, a house, invisible in a mountain.

• 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.
• 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.
• Build two mounds using the soil dug. Insert a residence between these two mounds.
• Built on "a new topography-mountain", all parts of the building are close to the earth. The mountains are designed to emphasize the slope.

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.

Mountains & Opening House - diagram, drawing courtesy EASTERN design office

B. Flying. An upper floor, a design room

• Observe the Gulf of Osaka, high-rise buildings, Kobe port, Kansai Airport, Itami Airport, and shadowy blue mountains.
• The land originally slanted at an angle of 18 degrees. Mounds are built there to let the slope undulate.
• These mountain waves are topography where no previous topography existed. The upper floor was designed to float on these mountain waves.
• 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?

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.

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.

Mountains & Opening House - diagram, drawing courtesy EASTERN design office

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.

Mountains & Opening House - diagram, drawing courtesy EASTERN design office

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.

Mountains & Opening House - diagram, drawing courtesy EASTERN design office

Putting the ideas of a "slope" into order. The correlation between rising and falling(?up and down) , crossing far and nearby nature. The multifarious worlds that people can sense in a place called "slope"

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.

Haven't you ever had the experience of gazing far into the distance, all alone in a spot on a grassy slope where adults will surely never come?

+ Description of technique and material

Deck on the Mountain

The Material of the Mountain
The outside (exterior) mountain is formed into a mound by piling up soil excavated from the slope. The surface of the mound is a type of raw material made from crushed marble called "Kansui". Glittering fragments of crushed marble on a whity surface shine brilliantly. There are two white mountains. The living quarters are inside the white mountain while atop the white mountainous wave is a deck.

One of the two white mountains functions as a structural support for this building, while the other mountain conceals the bathroom. These two mountains are also set into the living spaces of the residential quarters.

The Structure of the Deck
The framework of the upper floor is steel and the lower floor is reinforced concrete. The upper floor evokes a sense of being on the deck of a boat and in order to achieve this feeling architectural columns and walls are designed as to make one unaware of their existence.

Entering the house from the northern road, a 14meter wide opening and the 16.5 meter x3 meter terrace outside create the feeling that your own body is floating in the scenery. This is a deck.

To achieve this, we used two different methods.

1. Revaluation of the trusses
2. Concealing the structural members in the curves

1. It is not immediately apparent; however, since horizontal slits were cut into the northern wall, trusses were set into it. It is like the structure of a bridge. Bridges are set into the upper part of the horizontal slits which allow the floor to float in the air while concealing the structural device.

2. Columns are in the curves forming the openings and this also is concealed. The curves of the openings respond each other with the curves of the mountains. A fantasy created by the repeated curves appearing over and over again.

Living Space + Opening + Mountain
The lower floor fully utilizes the slope of the mountain. The hidden areas become mountains? while the areas that is required light become valleys. These rolling undulations are all part of the design.

Two Horizontal Eaves
The upper and lower floors are used in different ways. The upper floor is a design room. The lower floor houses residential quarters. That is there are public spaces within the residential quarters. The demand of how the spaces should be is different; therefore, the structure is also different.

Taking balance to unify the upper and lower portions, the curves of the mountain are made continuous with the curves of the openings. There are two thin iron plate eaves on the openings: one with the length of 14 meters on the upper floor and the other with 16.5 meters on the lower floor. The thickness of the iron plate is only 9mm. The straight line of these two eaves emphasizes the expansive spreading horizontal width of this house. Consequently, this makes you forget that the house is on a sloped site.

Blue and White
The overall whiteness is not just a general white coat of paint. It is white mixed with blue. This is because we want white that corresponds with the blue sky. In addition, we intend this white to reflect the light of fragments of marble scattered in the raw material which covers on the surface of two newly built mountains.

Mountains & Opening House - Basement floor plan, drawing courtesy EASTERN design office

Mountains & Opening House - 1st floor plan, drawing courtesy EASTERN design office

+ Project credits / data

Project: Mountain & Opening House
Location: Takarazuka Hyogo Japan
Usage: Office ,House
Site area: 711.46 m2
Total floor area: 361.84m2

Architect: EASTERN design office
Client: AMERICAN CLUB INTERNATIONAL CO, LTD
Structural Engineering: HOJO STRUCTURE RESEARCH INSTITUTE
Constructor: Fukasaka Co., Ltd
Photographer: Koichi Torimura
Completed: December 2009

+ All images and drawings courtesy of EASTERN design office