Credit: Wiel Arets Architects

Amsterdam-based Wiel Arets Architects (WAA) completed the A' House in Nishi-Azabu, a dense residential suburb outside of Tokyo characterized by low-rise houses and narrow streets. Enveloped in raised glass, the approximately 1,460-square-foot structure features oversized windows that can be extended by sliding the exterior wall-mounted segments along a track. Each window is multi-layered with two separate types of glazing: one that is transparent and one that is semi-opaque—the same finish as the entire exterior—so that residents can regulate the flow of natural light and their privacy. When the windows are shut, they cast a lustrous light within the interiors. Consisting of five stories, the narrow space is brought together by a spiral staircase.

The master bedroom, located on the top story, features a small, open-air terrace, accessible by sliding an opaque glass door. Another sliding glass partition, when it is retracted, opens up an expansive view to the neighborhood’s nearby park. The infrastructure is built of concrete, helping to achieve local regulations for earthquakes.

Due to the tight constraints the house is especially slender. To create a site that does not impose on its context—and have enough space to park a car—the designers integrated another fold into the southern façade at ground level.