While conceiving this Toyko home, Nendo founder Oki Sato sketched an immense staircase cutting through a cuboid building. This gesture gave the Stairway House its moniker—and the final product barely differs from the sketch. The residence by the multidisciplinary design studio combines poetic thought, simple gestures, and precise execution.

Each of the projects in Sato’s oeuvre—which runs the gamut of objects, branding, furniture, and architecture—contains a good dose of wit. As such, this house may be minimal in form, but it is certainly not austere. Using uncomplicated expressions simply helps Sato communicate his messages clearly.

The Stairway House was designed for Nendo’s chief operating officer, Akihiro Ito. He lives here with his immediate family, his parents, and the latter’s eight cats. The home nestles within a dense residential suburb, and the architecture both distinguishes and integrates the project within its site. From the street to the north, the house is a bone-white, windowless box—an aberration in the neighborhood of nondescript dwellings.

From this vantage, the home’s exterior does little to suggest the scale and identity of conventional residential architecture. However, at the south side, the house opens up with an entirely glazed facade. A rigid white grid delineates the home’s three stories.

This one-sidedness is deliberate, and it provides the interiors with ample daylight and views of greenery. The home is set back from the boundary to preserve a persimmon tree that has stood on the grounds for generations

In the forecourt, a large, ashen staircase rises from the earth, cuts through the glass facade, and continues into the house. The stairs are directly aligned with a long lane at front of the site, which provides the house with a deep view into the neighborhood.

Inside, the staircase terminates at a skylight, establishing a strong indoor/outdoor relationship that is exhibited throughout the building. “The idea was to connect the upper and lower floors, as well as the inside and outside of the house. I wanted this connection to be gentle, so I developed the step-like object,” says Sato.

The staircase is a dominant feature in the home, and it has multiple functions. The steps that extend outside the house serves as outdoor furniture, where the family can sit and contemplate the neighborhood’s comings and goings. The filigree of surrounding trees contribute pleasant shade for this activity.

For the feline occupants, the staircase is a playground, culminating in a lavish, sun-washed roof deck. For the elderly mother, it is an unconventional spot for potted plants where she can indulge her gardening hobby without having to step outside.

A plaster finish gives the staircase a homogeneous quality, so that it reads as a singular object. The rest of the interior is kept simple, with a monochromatic tonality, however oak floorboards warm up the space and keep it from feeling sterile.

The first-story study is a dynamic double-height space with a full view of the grown trees in the courtyard. The Twig armchair designed by Nendo for Alias has an equally vertical design language.

Unlike conventional houses, there is no front door in sight. The occupants enter the house via a subtle opening at the side of the staircase, which connects to the parents’ first-story abode.

Storage and services are tucked under the staircase, while a secondary flight of steps hidden within its larger counterpart leads to the younger family’s living/dining room and study on the second story, and bedrooms on the third.

The central volume functions like an atrium, funneling light and breezes throughout the house. Here, the staircase functions on both a symbolic and pragmatic level, providing an alternative—and fun—mode of traversing the house vertically.

During the day, the staircase appears to disappear when viewed from outside due to the glazing’s reflectivity. At night, the box glows and the staircase appears to quizzically end in a square of light at the roof, which perpetuates its otherness.

While many architects look to grandiose gestures as an end in themselves, the dynamism in Sato’s architecture stems from reevaluating basic components.

“I see design as being not about objects themselves, but the spaces between them. I’m inspired by overlooked things—like the gaps between floorboards. When you see normal things in a different way, they seem nonordinary,” he mentioned in a former interview.

Sato’s study and use of proportion, shape, and structure over superficial decoration reflect his keen understanding of human habits. The end result modifies—in both subtle and bold ways—the way occupants interact with space, adding a spark of the extraordinary to the humdrum activities of domestic life.

Related Reading:

When It Rains, This Japanese Home’s Concrete Deck Becomes a Reflecting Pool

In This Tokyo Home, a Dramatic Design Feature Takes Center Stage

Project Credits:

Architect of Record: Nendo / @nendo_official

Design Team: Oki Sato, Ishibayashi Noritake, Tsubasa Shindo, YSLA

Builder: Mizusawa Komuten Inc

Structural Engineer: yAt Structural Design Office LLC

Landscape Designer: SOLSO

Lighting Designer: ModuleX Inc.