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Office · Chiyoda, Tokyo · AI

Idein — Chiyoda: a pond to sit in on the second floor

Idein, an IT start-up, moved from one 500 m² room to a three-storey building of about 60 m² per floor after office use fell to 10 or 20 per cent. Takayuki Kuzushima Architects shaped the floors with 40 cm steps finished in mortar with rounded edges, like ground shaped by land and water.

Client Idein Inc.Location Chiyoda, TokyoCompleted December 2021Floor area about 183 m² (3 floors)Design Takayuki Kuzushima ArchitectsConstruction Cosmos More
The meeting space
The meeting space

Concept

Body scale

The aim was an office that a café or rental office could not replace: a place where people really gather. Its plan is made by the scale of the body rather than by numbers of seats.

People sit on the steps, which also divide areas gently and become small stands.

The open meeting space
The open meeting space
The open meeting space
The open meeting space

01 · Ground floor

A lab open to the street

The ground floor keeps the old floor level with three doors, making a lab connected to the town. AI cameras and monitors collect data every day. A raised area at the back holds a big bookshelf, a screen, a mini kitchen and a sound booth.

Inside
Inside
The workspace
The workspace

02 · Upper floors

A pond and a bench

On the second floor, a step shaped like a pond is ringed by counter desks and work tables; its carpeted bottom lets people sit on the floor and stretch their legs. On the third, a bench-like step around the meeting table separates booths and meeting space and becomes seating for presentations.

The workspace
The workspace
The workspace
The workspace
The meeting space
The meeting space
The meeting space
The meeting space
CompanyIdein Inc. ↗
DesignTakayuki Kuzushima Architects
PhotographyTakayuki Kuzushima Architects / Shingo Kanagawa
SourceTECTURE, “Office Idein”, re-reported by WALL ↗
PublishedOctober 2026
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