INTERSTICES 11

Tree-ness House
Otsuka, Tokyo

Akihisa Hirata Architecture Office 

The intention of this project is to develop the potential for a nature-like architec-
ture explored in our previous work, but the approach is developed further here. 
A tree consists of different parts such as roots, a trunk, branches, leaves and 
flowers, but these parts are not totally independent. The trunk and leaves differ 
in appearance, but are very similar in their basic structure – their inter-relation-
ship creates a kind of nested or layered organic structure. It is possible to create 
an architectural logic that creates a similar organically layered and “tangled” 
structure. The design seeks to develop this new architectural principle, with the 
intention of creating a complex ecosystem connected to the city.  



133

This building is a residential complex with spaces for commercial ten-
ants and is located in the Otsuka district of Tokyo. The site is narrow 
and deep, thereby defining the building as a narrow volume. In contrast 
to typical buildings that are simple stacks of floors, this design employs 
an organic layering system. It draws in elements not typically included 
in architecture, such as the street and other exterior spaces, generating 
fully three-dimensional spaces. Much as a tree defines various spaces in 
the air, this design creates for its occupants a “tangled” space character-
ised by ambiguous interior-exterior relationships.



INTERSTICES 11

BOXES: Boxes are composed into a layered volume that includes numerous voids. 
Within this volume, internal boxes define enclosed spaces like bedrooms and ex-
ternal boxes create terraces; more open interior spaces are defined with the voids 
by glass walls. 

PLEATS: The openings in the boxes have been pleated, creating an ambiguous 
relationship between inside and outside. 

PLANTS: Greenery is planted around these pleats, resulting in three-dimension-
al gardens around the building’s perimeter. The arrangement of functional vol-
umes and voids, openings, and greenery integrates and entangles the building 
into a single organic whole. 



135