Y-shaped wooden columns support rooms and lofts at different levels inside this family house in Matsudo, Japan, by Hiroyuki Shinozaki Architects (+ slideshow).

A total of eight columns stretch up to the roof of the house, overlapping one another to support a spilt-level first floor containing two bedrooms and a traditional Japanese room, as well as three separate lofts overhead.

The living room, dining room and kitchen are all located on the ground floor and are loosely separated into different zones by the gridded layout of the columns.

"Although the whole house is just one space under big roof, it is divided loosely with Y-shaped frames and floorboards," said Hiroyuki Shinozaki.

"I hope that the family uses the structure of the house in their daily life," the architect added. "For example, people hanging pictures and figures from Y-shaped frames and marking the height of their child on it. And they will leave the trail of their life on the house like a well-thumbed book."

A wooden staircase leads up to the split-level first floor, while ladders connect each of these rooms with the lofts directly above.

Flooring and furniture throughout the house is also wooden, matching the timber columns.

The roof of the house runs parallel with the angled wooden braces, as do the windows on the gabled facade.

An L-shaped terrace is positioned at the back of the building and wraps around the rear of the dining area.

Hiroyuki Shinozaki has completed two other houses named after letters of the alphabet in the last year. House K features a skinny west wing, while House T has huge rectangular holes in the walls and floors.

See more architecture by Hiroyuki Shinozaki Architects, including a cafe filled with courtyard gardens.

See all our stories about houses in Japan »

Photography is by Fumihiko Ikemoto.

Here's some project details from the architect:

House H

Client: family
Location: Chiba, Japan
Site area: 161.82 sq m
Built area: 64.02 sq m (39.56%)
Gross floor area: 115.41 sq m (71.31%)

Completion date: Dec 2012
Structure: Wood Flame, 2 story
Maximum height: 7.96 m

Project Team: Hiroyuki Shinozaki, Sota Matsuura, Tatsumi Terado Structural Studio
Structure engineer: Tatsumi Terado Structural Studio
Contractor: Hirohashi Komuten Lo.,Ltd.

Above: site plan

Above: ground floor plan - click above for larger image

Above: first floor plan - click above for larger image

Above: long section - click above for larger image

Above: cross section one

Above: cross section two

Above: east elevation

Above: north elevation

Above: west elevation

Above: south elevation