Tokyo’s first 5-storey wooden structure – an apartment building – is to be built near Shimouma in Setagaya-ku.

Under a revision to the Building Standards Act in 2000, wooden structures over 4 stories are permissible as long as they meet building strength and fire resistant regulations. Prior to this amendment, a law made during the Taisho period (1926 – 1926) limited wooden structures to 3 stories.

Although the amendment was made 12 years ago, it has not been widely taken up by the construction industry. In Tokyo city, just one 4-storey wooden residence was built in Chiyoda-ku in 2011.

The privately developed apartment building is designed by KUS ( and completion is scheduled for April 2013. The building footprint is 92.84 sqm and the total floorspace is 372.60 sqm (4009 sqft). There will be a retail space on the 1st floor, and floors 2 to 5 will be residential. Drywall (or gypsum board) will be used to bring the building’s fire resistance up to code.

This form of construction is also said to be more eco-friendly than concrete or steel-frame buildings. The construction cost, however, is about 20 – 30% higher than reinforced concrete, but is partly covered by subsidies provided by the MLIT to promote the use of wood.

If 4 and 5 story wooden buildings become more popular, construction prices should decrease. For 2 and 3 storey homes, wood is still the cheapest option available.

Source: The Sankei Shimbun, June 19, 2012.