All the rooms of this renovated Tokyo house by Japanese studio Naf Architect & Design are connected to a wooden box at its centre.

The architects liken this connecting room to an electrical switch box.

It contains staircases leading up and down, an entrance from the house into the client's chiropractic surgery and a small seating area.

Narrow grooves between each of the wooden slats let light filter inside and provide space for hanging picture hooks.

The living and dining room is located on the first floor just above, where the the roof of the box forms the surface of a kitchen worktop.

See more stories about Japanese houses on Dezeen here.

Photography is by Toshiyuki Yano.

Here's some more information from Naf Architect & Design:

Switch Box in House

This is a total interior renovation project of an existing house, installing a box made of deck lumber in the middle of the house.

The existing house is 17 year-old, two-story, 4-bedroom wooden structure on top of semi-underground garage. It could serve as home, but we could not see how and for whom the room layout was made.

New owner of the house is a family of three; a couple with a child. Installed in the center of the house is a hall-like space made by a large box which gives a doorway to chiropractic clinic run by the wife, to the bedroom of the couple, to the entrance of the house, to living and dining room upstairs, and to karaoke room in basement. As rooms of various purposes were relocated in the existing house, the composition of the house became more like that of a complex facility. The box-like space which brings together traffic lines and connects each room is, in a sense, switch box of traffic lines.

The box is made of deck lumber, whose top side has large interspace between lumber and let sunlight pour downstairs. On the sides of the box are smaller interspaces to avoid the gaze but large enough to let through the voices. It allows loose spatial continuity from the second floor to the basement and at the same time, interspaces are adjusted to keep privacy when there are guests. In the living-dining room on the second floor, the top of the box comes up to the height of a counter suitable for housework. High side windows on the sloped ceiling take in ample sunshine and the top of the box can be used as sunroom. Hooks can be placed between the deck lumber to hang pictures, hangers or foliage plants anywhere we like. There is almost no exterior space for garden within the premises, and it was our challenge to introduce various living scenes indoors by using the box.

The existing house before the renovation was one of many typical houses in the real estate market. In this renovation, we made Karaoke room in the basement, taking advantage of the sound insulation properties of concrete foundation. We see possibilities in creating new living environment by taking advantage of such properties.

Name of the Project: Switch Box in House
Location: Suginami ward, Tokyo
Category: detached house
Structure: Wood construction
Maximum height: 8.859m
Frontal road: 5.54m on the west
Site area: 71.51m2
Total floor area: 127.99m2
Completion: Desember 25, 2012
Architect: Akio NAKASA(director), Daisuke AOKI