Urban green and concrete – A futuristic, wild treehouse in Tokyo

Japanese architect Akihisa Hirata has completed a multi-story residential building in Otsuka, a district of Tokyo, that further expands his vision for connectivity between nature and architecture. It looks like a concrete treehouse and presents an interesting way to secure and redevelop urban greenery in the city. The residential building is located on a deep but very narrow site and is characterized by an asymmetrically structured structure.

Looking for a balance between nature and city life

The building's design is inspired by the structure of a tree. The concrete volumes are stacked to create several terraces and cavities in which the plants and trees are accommodated. This construction method led the architect to call the project the “Tree-Ness House.”

“Like a tree, we tried to create an organic architecture through a hierarchical combination of different elements such as plants, cavities and concrete boxes,” said Hirata. “The stem and leaves differ in appearance but are very similar in basic structure – their interrelationship creates a kind of layered organic structure,” he continues. “It is possible to create an architectural logic of floor order that has a similar structure.” The concept seeks to further develop this new architectural principle, with the intention of bringing urban greenery back into the city and creating a complex ecosystem.

Bringing urban greenery into harmony with exposed concrete

The openings in the facades are lined with a frame of white concrete, which Hirata calls “folds”. These folded shapes house functions such as window sills, tables, stairs or doors, creating an ambiguous relationship between indoor and outdoor spaces. “I intended to create a futuristic and wild architecture that awakens human animal instincts, blurring the line between inside and outside,” said the architect.

Although it is primarily a residential building for oneMulti-generational familyThe concrete treehouse also contains commercial spaces on the lower levels. A few stand-alone apartments and an apartment for the family's grandmother occupy the first floors above the ground floor, with the main apartment spread over several levels.

There is parking on the ground floor of the building, an office at the front with a gallery at the rear of the building.

A central space was created in the middle of the building, providing a visual connection between the different levels. From there you also have a view of the sky. Large windows and glass walls allow daylight to penetrate the rooms. Exposed concrete is used for both the facade and the majority of thefloors and ceilingsused inside.

In some areas, materials such as wood and leather are used to create a warmer tone and better texture. A small home office is lined entirely with wood, while a small corner room features flooring and a bench covered in brown leather.

Many of the rooms have balconies that invite you to linger. Planters create even more atmosphere and also serve as privacy screens. An external staircase leads to a roof garden that offers expansive views of the city skyline.

Architects:Akihisa Hirata
Ort: Toshima, Japan
Projektarchitect: Yuko Tonogi
Design Team: Kohei Oba, Masatoshi Sugiyama
Usable area: 331.38 m²
Project year: 2017
Photos: Vincent Hecht