Located on a steeply-sloped site in a residential neighborhood of scattered houses, razor-thin alleys, and tightly packed apartment houses, Portland-based Architecture W’s M House doesn’t have a lot of room to breathe. That’s not surprising, considering it’s located in ultra-dense Nagoya, Japan. So the task for firm principals Brian White and Michael Weenik (who lives in the house with his family) was to give it the illusion of lots of space. The restrained, box-shaped house, clad in a thin pattern of corrugated metal, does indeed feel spacious, thanks to creative siting, massing, and lighting.

The first major space-maximizing move was a surprising one. Despite the inviting mountain views to the north, the firm cantilevered the house (via steel trusses) 15 feet over an adjacent alley to the south, providing a place for parking and for Weenik’s son to play. On this newly-created plinth, the firm built a small, concrete-lined reflecting pool, filled with lilies and set with elegant square steps. Underneath, the architects fit an underground apartment for theWeeniks’ in-laws, a common concession in a country where older parents almost always live with their children.

Above the cantilever, there’s an airy living area clad with exposed concrete walls and floors, enclosed on both the north and south facades by floor-to-ceiling sliding glass walls that open completely to the distant mountains, not to mention the sun and breezes. The north-facing elevation feels almost impossibly open because it has no railing (building rules are not as strict in Japan). Light pours in, thanks to a glass-enclosed yellow stairway leading to a large, top-floor roof deck and a dramatic circular skylight. Space in the open-plan main space is used in a familiar Japanese way. One single white wall, beset with built-in plasterboard cabinets, contains almost all of the house’s storage space, including a Murphy bed.

White and Weenik had worked together in Japan for the San Francisco firm K+D before starting their small practice—with footholds in Portland, Nagoya, and Tokyo—in 2001. White said they like to bring the best of Japan and the U.S. to their work. The American touch includes bits of nature like the reflecting pool and the wide-open expanses, and the Japanese touch comes from the superb craftsmanship and concrete work (thanks to highly trained local builders). The overall effect, White suggests, is smart yet serene because of the house’s simplicity. “Why get too tricky? This works pretty well,” he said.