Japanese architect Kentaro Ishida has completed a steel-plated house on the outskirts of Tokyo, featuring an asymmetric pitched roof designed to maximise sunlight for residents (+ slideshow).

Ishida – who set up his studio KIAS after working for Shigeru Ban and Herzog & de Meuron – gave U House a tall pitched roof to allow daylight to filter down to a strip of garden between the building and its neighbour.

This upper portion of the 190-square-metre residence is covered in horizontal bands of galvanised steel – a popular cladding material for houses in Japan.

"The house sways its roof away from the neighbouring building in order to provide more daylight to the narrow garden below," explained Ishida.

"We believe this formal imperfection gives softer spatial experiences that can also be seen in Japanese traditional houses."

The structure has a concrete base made of up of two boxes, featuring slatted timber doors. The walls are imprinted with a stripy pattern left behind by the wooden formwork used in the casting process.

An entrance hall with grey flagstone floors and floor-to-ceiling glazing is set between these two textured concrete volumes. This space opens out to the garden.

This arrangement separates a double garage on one side of the ground-floor plan from an en-suite master bedroom on the other.

The bedroom window is positioned low in the wall to allow residents to enjoy views of a rockery from bed.

A wooden staircase ascends from the entrance hall to the first floor, where a combined living and dining area is set under the lowest part of the roof.

A kitchen sits on the other side of the stairwell, forming a buffer between the primary living space, a study and bathroom.

Up another flight of stairs on the smaller second floor, a guest suite is positioned beneath the irregularly pitched roof. A glazed wall separates this space from a sunroom with an angular skylight.

Spaces throughout feature light wooden floors and furniture, and a combination of white-painted and raw concrete walls.

"The combination of soft and hard materials, and various spatial proportions creates richness for the owner to enjoy each and every living place throughout the seasons," said the architect.

Other steel-clad houses in Japan include a residence with a tilted roof that is designed to look like an open box, a grouping of gabled towers that join to form a single house and a two-toned home with a bulky metal-clad base.

Photography is by Toshiyuki Yano.

Project credits:

Architect: KIAS
Project team: Kentaro Ishida, Yuji Ito and Miyuki Kakizawa
Structural Engineer: Takashi Manda
HVAC Engineer: Chiku Engineering Consultants
Construction: Ogawa Kensetsu