The 43-story head office is the first of what Nikken calls its “third generation” high-rise buildings, wherein design cosiderations include a substantial concern for the enviroment. In these Nikken buildings such concerns significantly shape the structural system an the overall form. Housing the headquarters of the well-known Japanese electronics giant, the building, as it soars upward, becomes narrower by two setbacks. The resulting shape ensures longer hours of sunshine to the surrounding area.

The designers also took advantage of the relatively generous site and surrounded the building with a “forest” of planted trees and greenery. Moreover, recognizing that high-rise structures create considerable wind turbulence at street level, the architects designed a large urban window: the building is pierced by a 42 meter wide and 15 meter high opening above the twelfth floor, after which the structure narrows. This solution could only be achieved with a large-span structural system. The super frame, applying box-like super columns and truss beams at every tenth level, concentrates the vertical load of the structure at its two shorter sides, wherein the vertical circulation, elevators and stairways, is also arranged.

This structural system, along with de “urban window”, allowed for the inclusion of a large atrium within the lower section of the building: this 45 meter high and 30 meter square atrium is outfitted with a same-size, crystalline skylight. In good weather teh skylight can be rolled away, opening the space below, which is protected in case of rain by the upper section.