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Office · Edogawa, Tokyo · Office conversion

Triangle-Roof Office — Edogawa: a ready-built house turned office

On Ring Road 7 in Ichinoe, Edogawa, Tokyo, Motoharu Akiyama Architects converted a typical ready-built house with a gable roof, balcony and ALC walls into a 128 m² office, without a major remodel. Elements were taken apart and rebuilt so that a closed collection of private rooms became an open space facing outward.

Location Ichinoe, Edogawa, TokyoCompleted July 2018Floor area about 128 m²Design Motoharu Akiyama ArchitectsConstruction Suiko
The building
The building

Concept

From house to office

White, neutral interiors remove the warmth and domestic feel of the house. A band of windows, typical of offices, separates the roof, so a geometric mass seems to float above the gable.

The eaves were cut and a new roof added for a sharper shape; the balcony was lowered and capped with stainless flat bar.

The building
The building
The building
The building

01 · Scale

Taller rooms

The ground floor ceiling was raised to 2.7 m and the upper floor follows the roof pitch, changing the low scale of a house to the open scale of an office. Downstairs are a meeting room and storage; sliding doors open the meeting room to the entrance hall.

The entrance hall
The entrance hall
The stair
The stair
A meeting room
A meeting room

02 · Street and houses

Two faces

The east side, on the busy ring road, is a symbolic face for the company; the west side, facing houses, has a fence of selangan batu wood for warmth. Upstairs, the one-room office is divided by partitions so people sense each other everywhere.

The workspace
The workspace
A meeting room
A meeting room
The guest room
The guest room
The workspace
The workspace
DesignMotoharu Akiyama Architects
PhotographyNaohito Sakuma / Motoharu Akiyama
SourceTECTURE, “三角屋根のオフィス”, re-reported by WALL ↗
PublishedOctober 2026
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