Toranomon Hills Towers, Tokyo

The Toranomon Hills Tower, one of Tokyo’s tallest skyscrapers, is flanked by two impressive new companions: an office tower, 36 stories and 185 metres high, and a residential tower, Japan’s tallest residential skyscraper at 54 stories and 220 metres high. A green, publicly accessible plateau connects all three high-rise buildings at the first above-ground level. ingenhoven associates is the first German architectural firm since 1895 – since the headquarters of the Japanese Ministry of Justice by Berlin architects Hermann Ende and Wilhelm Böckmann – to build again in the Japanese capital.

The central design element is the rich plant life that interweaves the skyscrapers with their environment. The two new towers integrate well with the surrounding neighbourhood, respecting the taller central tower while presenting their own contemporary urban response. They reflect the greenery of the adjacent parks and gardens of the historic Atago Shrine, a Shintō shrine dating back to 1603. The towers fan out towards the ground-level zone in stepped terraces with a public green plateau above the plaza at street level. The plateau is reserved for pedestrians and links all three towers together, providing access to the cafés and restaurants in both new high-rises, along with shops, a large lobby, and coworking space in the office tower. Benches invite visitors to linger and enjoy the exercise areas and tranquil fountains – a place of balance with zones of calm amid the rush of the largest city in the world.

The towers are designed to accommodate possible earthquakes and typhoons, for example, through appropriate building component dimensions. Like ancient temple buildings, the high-rises are structurally configured to passively dampen seismic vibrations. Both towers are characterized by decks finished in white, powder-coated aluminium, which serve as sunshades and balconies. In the residential tower, each of the 550 condominiums and serviced apartments has its own balcony. Shared facilities include a spa, pool, guest rooms, fitness centre, and childcare. The protruding decks also include space for the greenery planted up to the seventh and eleventh floors, respectively. These plants were selected according to their location on the buildings in terms of elevation and wind exposure. Trees and shrubs were planted up to the second floor; for the levels above that, shorter plants were chosen. The office tower also has a rooftop garden. The total green area of the ensemble is approximately 7,800 m2 and includes numerous tall trees. This achieves a green replacement rate of 64.5% and a CASBEE “S” rating – the highest level in this classification. With a new metro station on the Hibiya Line on the lower level, plus an express bus station providing transit to both intercontinental airports, the new towers are optimally connected to the public transport system. The Toranomon Azabu Dai complex is the largest urban development project by Mori Building and was initiated by Minoru Mori (1934–2012), a notable Japanese businessman and president of Mori Building, one of the largest private real estate developers in Japan. The name “Toranomon”, Japanese for “Tiger Gate”, recalls the southernmost gate of the Imperial Palace that once stood at this site, which was demolished in the 1870s. Today a lively district is being built here in the heart of the Minato district in Tokyo’s southern centre, with apartments, offices, a hotel, school, sports facilities, and more.