Japan Post Office

Architecture
JAHN, Chicago/USA (design architect) & Mitsubishi Jisho Sekkei Inc., Tokyo/Japan (general planner)

Planning time
2008 − 2009

Construction time
2009 − 2011

Services by Werner Sobek
Structural engineering of special structures (WP 1 − 5 acc. to § 64 HOAI)

GFA
206,000 m²

Client
Mitsubishi Jisho Sekkei Inc., Tokyo/Japan

Photography
Rainer Viertlböck, Gauting/Germany

Awards
BCS Award (Building Contractors Society) 2015
AIA Chicago Distinguished Building Award 2016 – Citation of Merit

The redevelopment of the historic Tokyo central post office included a 200 m high tower rising out of the renovated historic building. The special structures comprehend a 39 m wide triangular atrium skylight, the entrance canopy, as well as several screens located in the north and west facade. Among these the most challenging one is the north facade top screen, which is 31 m high and 61 m wide. The screen is characterized by three asymmetrical folds lines and, despite the high degree of transparency, has to withstand tornado winds up to 8,5 kN/m² as well as earthquake acceleration up to 120 % of the earth gravital acceleration. In 2015, the building was awarded the 56th BCS Award of the Japanese Building Contractors Society.