A triangular courtyard slices through the centre of this woodland retreat in Nagano, Japan.

Architects Kyoko Ikuta and Katsuyuki Ozeki designed the house, which is named Forest Bath.

The triangular void separates the house into three sections, comprising a living room at the centre, a bedroom in the west wing and a bathroom in the east.

A wall of glazing separates the living room from the courtyard, while the surrounding walls frame a view of the trees and sky.

Some other woodland houses in Japan we've featured include one composed of five connected cottages and another with gabled concrete walls - see more projects from Japan here.

Photography is by Tomohiro Sakashita.

Here's some more information from Ikuta:

Forest bath

This is a summer house situated in the forest. In this house, by "digging a triangle plane into a house figure", the view extending obliquely upward was gained. Since the site is comparatively flat, a specific view does not open, like hills, but the big Japanese larch which has grown over ten meter is beautiful. Because the views of the larch branches cannot be caught by adopting horizontal openings, we considered catching it by the opening in a slant direction.

Wooden shade is reflected in the center room dug by the triangle from a high position, and it changes every moment as time goes by. A natural expression is translated and expressed in forms, such as the shade of a tree and light, on a white canvas. Moreover, a sense of distance with trees is adjusted depending on how to place yourself, and it provides a spatial experience filtered with depth.

On the other hand, the rooms of both wings are contrastively darker than the center room, and they are illuminated by the wavering light coming from the center room. Through the low eaves, the view enters the space which leads to the bottom grass of the woods.

Click above for larger image

Project title: Forest bath
Location: Nagano, Japan
Use: Summer house
Completion: 2010
Steel construction
Land area: 590.94㎡
Total floor area: 71.37㎡

Architects:
Kyoko Ikuta / Kyoko　Ikuta Architecture Laboratory
Katsuyuki　Ozeki / Ozeki Architects & Associates

Structural engineering: IIJIMA Structural Design Office
Constructor: Daiichi kensetsu