Tatsumi Apartment House

by Hiroyuki Ito Architects

Client Hiroko Abe
Awards RIBA Award for International Excellence 2018

Tatsumi Apartment House is a 10-storey tower on a 7.5 x 5 m plot containing two commercial floors, six studio flats and a top floor duplex. It is an ingenious and highly efficient use of a tiny site where every inch of space is employed in plan and section. Whilst families tend to move to suburbs, it caters for a young demographic who wish to live in the city centre. An exemplar of micro living where architecture, engineering and furniture design combine.

The building is organised structurally around six columns and three beams creating a stepped section, which divides the small floorplate into places for cooking, eating, sitting and sleeping. A structural logic based on lightening loads as you ascend the building, for seismological reasons, creates a variety of different steps, niches and ceiling heights, making every flat unique.

Internally the apartments are meticulously detailed and proportioned to take account of varying activities, in particular incorporating the Japanese tradition of sitting on the floor. House becomes furniture, domestic functions are part of the structure and architecture. It successfully makes links with traditional Japanese architecture and concepts of space.

Windows are carefully placed to make the most of views out, each space has natural light from four sides and views on two sides, which with the changes in floor and ceiling heights make each flat feel spacious despite the 35m² footprint. The architect has seen this as a prototype now being expanded into different projects.

A rich multi-layered project, it makes a positive contribution to Japan's ad-hoc cityscape.

Date of completion April 2016
Location Tokyo, Japan
Cost Confidential
Internal area 352 m²

Contractor Sanyu-Kensetsu co.