This house is composed of a simple diagram: two tubular spaces interwoven within a slender volume measuring 4.5 meters in width and 21.5 meters in length.
The design theme is to explore and express the spatial richness inherent in such narrow proportions.

The two tubes are painted white and blue. The white tube runs the length of the second floor, bending slightly in plan. It contains the living room and balcony in a linear arrangement and functions as an open, outward-facing space. In contrast, the blue tube extends from the first floor to the second, varying in cross-sectional shape as it rises. It includes a Japanese-style room, bathroom, toilet, study, children’s room, and bedroom—forming a relatively enclosed and private space.

Each room in the blue tube can be separated by sliding fittings to form individual enclosed rooms, but when all fittings are retracted, the entire interior becomes a continuous, unified tubular space.

The ends of the two tubes house spaces intended for extended occupation—such as the living room, Japanese-style room, and bedrooms. The central area, where the two tubes overlap and intertwine, serves as a circulation zone with an entrance, stairs, and ramps. This zone is designed to maximize visual connectivity from the main rooms, allowing one to fully experience the depth and richness of the narrow yet elongated space.

As one's viewpoint shifts through the central circulation area, various spatial qualities emerge—front-to-back depth, vertical continuity between floors, lateral expansion, and transitions between open and closed areas. These layered spatial experiences highlight the subtle complexities and richness achievable within a slender architectural form.