Yvette Leeper-Bueno and Adrian Bueno’s home, on West 112th Street in New York, is recognizable by its two-story bay window angled to bring light and views into the dark, narrow structure. Seemingly a single, seamless unit, the stair is composed of two elements—treads and mezzanine—and held in place by two distinct strategies: The stairs are welded to, and cantilever out from, a series of steel tubes concealed in the walls; the mezzanine is attached on one side to a steel beam, and hung at two other points from rods attached to the roof structure. Photo by: Adam Friedberg