a+u Architecture and Urbanism Magazine

Hideyuki Nakayama Curves and Chords

A home office for a married couple in Tokyo. The 7.5-meter-high interior space is divided vertically by slabs placed at ten different heights. It is structured so that privacy increases from low to high levels. The building is designed as much as possible to not define specific uses, so that a floor can become a counter depending on how things are placed on it, for instance.

A variety of ideas comes together evenly with the building’s layered floors, and various furniture materials and colors.

Looking up, one sees the orthogonal hatching formed by the joists of the slab decks and the straight chords of their edge girders, as the light from the skylight above reflects off the white walls illuminating every corner of the building. The interplay between the joists and the decks creates openness and differences in functionality on each level.

The largest slab girder is 12.2 meters long. The structure makes use of “hyperbeams” (fixed exterior dimension I-beams), and those with expected high deflection were cambered at the factory.
The floor can also be used as a desk. In order to create legroom, the girder is offset 350 mm from the edge. In addition, the composite slab deck is 25 mm thinner than typical and is varied in area and span.