OMA’s Toranomon Hills Station Tower: a study of contemporary architectural collaboration

Due to be completed in 2023, Tokyo’s Toranomon Hills Station Tower will be one of the world’s largest urban hubs for transportation, hospitality, business and retail. Architect Shohei Shigematsu, director of OMA’s New York office, spoke on Tuesday at our Brainstorm Design conference in Singapore, introducing the vision of a building that responds sensitively to urban context.

‘Often this kind of conference is where architects present their work. That’s a one-sided [point of view]. So I’ve brought the client on stage too,’ he said. He refers here to Midori Omori, senior general manager at Mori Building Co., the leading developer in Japan. Mori has a track record of commissioning overseas architects - previously Cesar Pelli and Kohn Pedersen Fox – which Omori admits has baffled many people. Foreign collaborators can be ‘egoistical, stubborn, and out of control’, she has been told, so what makes them worth their while?

‘Discussion,’ she offers. OMA, who were awarded this project in 2016 following a design competition, stood out for their eagerness to converse with Mori and find out what exactly they are looking to achieve - in this case, a building that would complement its densely developed neighbourhood, rather than exist as an isolated entity. ‘An a la carte approach to architecture, rather than a bento box one,’ offers Shigematsu.

Having gone through multiple proposals that were sent back to the drawing board, both architect and developer agreed on a building with public space at its core (aligned along a vertical axis, and visible from many vantage points thanks to the building’s gently contorted form). A new metro station underneath spills into a grand plaza and concourse, the first of its kind in Tokyo. Adding to the building’s appeal is an infinity pool on the roof, with views of the Imperial Palace.

‘I shared the bento box analogy with [the Mori team] before we entered the competition - which is a bit risky, as it could have been taken as criticism,’ Shigematsu continues. ‘But this actually resulted in a shared take on how we can advance our design, by observing the changes in the world right now.’

From competition to completion, the Toranomon Hills Station Tower project will take seven years. Mori believes it is time well spent. ‘I learned from Roppongi Hills (another Mori project, by Kohn Pedersen Fox) that deep conversations lead to buildings that people really want to visit, work in and live in. Knowing people’s wishes and giving them form is the true power of design.’

For now, both architect and developer are continuing to find out people’s wishes. ‘We’re still hearing ideas about how to position its facility and programming,’ says Shigematsu. ‘It’s a work in progress.’