四万十の家 House of Shimanto

Shimanto Town, Tomioka-gun, Kochi Prefecture. The Shikoku Mountains lie to the north, the Pacific Ocean to the south, and the clear Shimanto River flows through the center of the town. The area is a plateau, but it is also a basin surrounded by mountains, and the Shimanto River runs through it, making it prone to fog. The phenomenon is most noticeable from summer to autumn, and rainfall is heavy throughout the year.  
The house is located on a corner lot on a two-way road in a spacious rural landscape.

Although it is a beautiful setting, the following conditions had to be properly addressed in order to build a house here: "heavy rainfall" and "a national highway facing north. The two conditions were "heavy rainfall" and "the national highway facing the north.
In the case of heavy rainfall, we sought ways to avoid damage from heavy rainfall.

This was a primary concern because the area receives a lot of rainfall. The national highway has a lot of traffic during the daytime, and the noise from passing cars and the eyes of drivers are problematic.
The question was how to provide a comfortable living environment while protecting the daily living environment in the face of these site conditions. This project started with this issue at the core of the design.

First, as a countermeasure against heavy rainfall, the roof was designed to be as simple as possible to prevent rainfall, and the overall plan was developed step by step so as not to interfere with the drainage plan inside and outside the site.

The view and noise from cars were solved by closing the building to the road on the north side and opening the frontage to the south side. The rooms are arranged according to a clear structure, and at the same time, we paid attention to the exterior design.

We wanted to express a functional and unique character that blends in with the landscape but is not banal. In order to link the elongated nature of the site's surroundings to the interior, the sloping roof shape was utilized to ensure high ceilings. High sidelights were used to provide ventilation, ventilation, and lighting.

Air circulates with the flow of the wind, improving indoor comfort. In addition, even on cloudy days, the brightness of the interior can be dramatically improved by bringing in natural light from a high position.

The large openings on the south faces of the living room and bedrooms provide a line of sight that extends from the interior to the outdoors. The floor is also equipped with flexible sliding doors that can be opened and closed as needed. The line can be drawn softly according to the adjustment of cold and warmth and the way each family member spends his or her time.

Gently dropping one's gaze from the raised ceiling, one can look out over the spacious interior. The south side of the house is visually connected to the tranquil countryside beyond.This continuity creates a sense of spaciousness.

The exterior design is also based on the concept of "connection," and expresses a sense of continuity with the land, as if there were a small mountain in the midst of the tranquil rice paddies.

Shimanto Town is a national cultural landscape district. The forests, where the Yairochou butterfly flies over, the clear Shimanto River, and the scenic Komuro beach. The mountains, rivers, and ocean - this area, nurtured by abundant nature, is endlessly generous. In this project, we were continually impressed by the unpretentious gentleness and strength of this land.
We have also been deeply considering "what the building should look like there," not only now but also in the future.

Buildings accumulate years together with nature. Natural scenery moves people's hearts because the more time passes, the more it matures.  The true value of a building is in how it matures and deepens with the passage of time.

Buildings become old as time passes, but the meaning of their existence evolves. We have approached this project with this in mind. This pursuit is the core of our consideration of the "significance of design," and it is something that is always present in the foundation of our work.


  • Completion 2012.03
  • Building site Tomioka-gun, Kochi
  • Principal use private residence
  • Photo Nacasa&Partners


  • 2014 2014.01architecture culture No.392(韓国)
  • Minimalissimo
  • Looksee
  • archdaily
  • arthitectural
  • Doums