Why do the Japanese build wooden houses

Record wooden house in Tokyo: cedars and cypresses

A green meadow of flowers, a small kitchen garden with fruit and vegetables, a wildly twisted, screwed tree, which with its gnarled branches protrudes like a sculpture from the outdoors into the interior. But what in the first few seconds gives the impression that you are sitting in a Shinto shrine, perhaps in a wooden temple, with crawling insects and chirping winged creatures, turns out to be something torn into the middle of the skyscraper on closer inspection as soon as you open your eyes Atrium, the breeze whistles around your ears, somewhere between the 60th and 70th floor.

One meter in altitude for every company year

According to the Japanese forest company Sumitomo Forestry, what is still a dream of the future today will turn out to be an extremely real present in the next 22 years. For its 350th anniversary, the empire founded in 1691, which has taken care of the management of Japanese forest areas since then, would like to reward itself with a new company headquarters. In Tokyo's Marunouchi district, a 350-meter-high wooden high-rise will be built, which will be named W350. One meter of altitude for every existing company year. Reported construction costs: 600 billion yen, around 4.8 billion euros. Planned completion: 2041.

Materials research

"Wood has played an indispensable role in Japanese architecture for some time," says Akira Ichikawa, President of Sumitomo Forestry Co. Ltd. "Wooden houses create a unique atmosphere for people and a pleasant environment for plants and organisms. By specializing in promoting material research and technological developments and manufacturing techniques in this area, we want to promote wood as a sustainable building material."

According to the OECD, Japan has the second highest proportion of forests in the world after Finland. 68.5 percent of the Japanese land area is covered by forest. Around a third of this was artificially created in the course of the last decades and centuries, with the plantings after the Second World War mainly concentrated on the two tree species most important for the Japanese construction industry - cedars and cypresses. "This wood is now grown in large quantities and ready to be harvested," says Ichikawa. "We want to set an example with the W350 project."

90 percent solid wood

The 70-story mammoth project is being erected on a floor space of 70 by 70 meters, with the house rising into the sky like a hollow tube, like a kind of cannellone. The inner courtyard, which will be connected to the outside world by large atriums integrated into the facade, is not only used for lighting, but also for access in the form of lifts and staircases leading across nothing. 90 percent of the skyscraper is made of solid wood: columns, pillars, beams, ceilings, floors, walls, interior fittings. The construction is complemented by a steel, external supporting structure, which is intended to give the house the necessary elasticity and earthquake resistance.

"A wooden house 350 meters high sounds like a dream of the future," says architect Tadao Kamei, CEO and President of Nikken Sekkei. "But if the client didn't want to wait until 2041, we could actually start building today." With 2,600 employees, the office, which was founded in 1900, is one of the largest and oldest architecture firms in the world.

Japanese architecture

In its 120-year history, Nikken Sekkei, which today operates branches in Asia, Europe and the Middle East, has already completed more than 25,000 buildings. The Architekturgalerie M√ľnchen is currently dedicating a solo exhibition to him that highlights the issues of ethics, respect and sustainability in this gigantic company.

"Japanese architecture without wood is inconceivable, but with the strong growth of cities after 1950, the material has almost completely disappeared from the cityscape," says Kamei. "We want to close this gap and make wood visible again as an urban construction material."

In any case, the use of this scale is unique: the building's vertical laminated beam pillars alone will have a dimension of 2.30 by 2.30 meters in the foundation area. An important detail on the side: Even now, although the project is still in the conception phase, Nikken Sekkei is working intensively with craftsmen and carpenters.

Record building from Vienna

The currently tallest wooden skyscraper with a total of 18 floors is located in Vancouver, Canada. The 24-storey Hoho in the Seestadt Aspern will soon break the record. "In any case, there is plenty of raw material for wooden houses," says Georg Binder, Managing Director of Proholz Austria. "In the Austrian forests alone, an entire single-family house grows every 40 seconds. If you consider that the proportion of timber construction in the Austrian construction industry is currently around 22 percent, the potential is far from being exhausted." (Wojciech Czaja, 9.2.2019)