Tachikawa City Hall Tachikawa-shi, Tokyo


Ideas for the project were solicited from the public in a design competition. The accepted proposals included low-rise large-span form, open ceiling, rooftop greenery, parking garage with isolation layer, and use of precast concrete (PC) for the building frame. The design work was carried out jointly by local citizens, the municipal government, and assembly, in an open process resulting in an original, unique design.
As a core feature of the overall design, ecological measures have been incorporated from many different standpoints of the building operation. For example, the impact of external heat is reduced by rooftop greenery, canopies, louvers, and other means; a building frame thermal storage air conditioning system makes use of night purge ventilation; localized air conditioning is adopted; and natural energy is used to the extent possible.

Structure PC
Floors 4F/B1F
Total floor area 25,981㎡
Completion Mar-10
Award Mar-10
Note Designed by a design collective of Masamitsu Nozawa and Yamashita Sekkei