Designed by Japanese studio Tato Architects, the rationale for the eclectic layout addresses the family’s desire for seamlessly linked interior spaces that facilitate a sense of closeness. Scroll ahead to see how this one-room dwelling has been built on various levels, all connected by a spiraling sequence of wooden steps and platforms.

“The client requested that the members of the family can feel close to each other regardless of where they are in the house,” says Yo Shimada, founder of Tato Architects.

The family of three was looking to create a space that was as transparent and open as possible, so they did not want any private rooms or covered storage areas in the house.

“The spatial structure that is constructed by repeating a simple autonomous system is similar to an ‘echo chamber’, which amplifies the innermost lifestyle of the client, and conveys a sensitivity that expands without limit,” explains Shimada.

The 535-square-foot building has an interior volume that’s about the same scale as a two-story house. Within this volume, Shimada has created a series of 13 angular platform floors that serve as multi-functional zones. This has resulted in the creation of close to 1,018-square-feet of usable floor space spread across the different levels.

Each platform is positioned 2.3 feet above the platform below it, and the difference in height allows the floor surfaces to have multiple purposes, as they can serve as shelves, tables, or seating.

The floor on the entrance level—which accommodates a coat rack and bike storage—spirals upward along two sides of the space, and converges at a central living area before separating and ascending toward the main bedroom and bathroom at the top of the house. From there, steps lead to two rooftop terraces.

“By using this combination of two spirals, we were able to create multiple paths inside the house that allow different room compartments so the home can accommodate changes in the lifestyle of the client,” states Shimada.

The framework that supports the 13 floors was constructed with steel to conform with local fire regulations, and the platform floors were made of steel beams.

The lower six floors are raised on 0.25-feet-high square steel pipes, while the seven floors on the top are suspended from the roof beams with 0.07-feet-long steel rods.

A short set of timber steps with black metal frames connect each of the platforms, and bring a sense of warmth to the white, minimalist interior.

Once the family moved in, they began filling the various platforms with their furniture and possessions, creating an eclectic and highly personalized space that will expand organically as their lives unfold.

Project Credits:

Architecture: Tato Architects

Builder: Seiyu Construction Company

Structural engineering: Takashi Manda Structural Design