There’s nothing particularly novel about building houses out of wood. In Sweden, the tidy white-trimmed red cabin — always in a lushly verdant landscape — is virtually a national trademark. But now it’s even becoming common to construct blocks of multi-story apartment buildings in wood. Using traditional materials in modern buildings is a climate-smart solution that may soon become an element of Chinese urban planning.
For Swedes, it’s of course perfectly normal to build houses of wood, and most people don’t give much thought to the climate considerations. Trees consume carbon dioxide in the air for photosynthesis as they grow, binding climate gasses until the wood decomposes. And wood is a lightweight material that requires less energy for transportation than materials such as steel and concrete. At the same time, wood offers high strength and other technical qualities.
The environmental benefits of timber inspire AIX Architects, a Swedish construction company that applies modern wood building techniques to apartment buildings and other large structures. Now AIX is betting that the trend toward green buildings will fuel growth in a major Swedish export commodity. Among other markets, AIX is looking toward China.
A ready market
There are plenty of good reasons to introduce modern wood building technologies to the Chinese construction industry. A shift to more wooden houses would not only facilitate China’s stated goal of limiting its climate change footprint, but it can also support development of Chinese forestry. For the time being, however, Chinese construction laws resemble those that existed in Sweden before 1994, when it first became legal to build multi-family apartments in wood. Progress was slowed by concerns about fire hazards and the perception that wood would be more expensive than other materials. But with the new legislation, attitudes slowly began to change and wooden houses with up to six or seven stories are now fairly common in Swedish cities.
Lars Johansson, a partner in AIX Architects, believes that the Swedish experience has bearing on wooden building material restrictions in China. “It’s not necessarily true that wood is the most combustible material,” he says. “It all depends on construction techniques and how the building is protected.” AIX has worked with modern timber engineering for decades, and has shown that it’s possible to bring down costs through industrial efficiency and mass production.
Steel and concrete are the dominant materials for modern building construction in today’s China, but there is also a general admiration for wooden buildings. “Many historical buildings are made of wood. Some single-family wooden homes are built, but they’re considered very exclusive and the very idea of apartment buildings in wood is still alien. When we explain about the advantages of combining modern techniques with wood as raw material, we get very positive feedback,” Johansson says.
The company delivers semi-finished construction modules such as walls and floors to the Chinese house. In effect, Swedish forest products are flat-packed in shipping containers for delivery to China, where they’re assembled into buildings of eight to ten stories.
Johansson explains: “For some time now, the Chinese government has been encouraging the re-planting of the nation’s scarce short supply in China. The forests may be ready for extensive harvesting in 20 to 40 years, but it’s possible to create demand for wood in the construction industry before then. One avenue is using Swedish forest materials, which are processed here and shipped to China.”
Johansson points out the importance of a holistic perspective so that each step in the process generates as little carbon dioxide pollution as possible. That means finding the right level of processing for the semi-finished modules in Sweden before they’re shipped to China in containers. Swedish companies are focusing on research and development, in combination with pilot projects, to help change attitudes toward wood building technology in China and, in the longer run, hopefully also modifications in construction codes.
Swedish eco-tech popular in China
AIX is just one of several examples of how Swedish-Chinese cooperation in environmental technology is on the rise. China is already Sweden’s second largest market for environmental technology exports, and the Center for Environmental Technology at the Swedish Embassy in Beijing is working to expand that trade.
Particular focus is placed on urban development. With several eco-cities planned around China, the Swedes are seeing an opportunity for mutually beneficial cooperation. The Swedish Consortium of Architects & Engineers, which includes AIX and eight other Swedish companies, is in negotiations for projects on behalf of the Chinese metropolis Caofeidian Eco City. An agreement would represent a great opportunity to demonstrate Swedish leadership in environmental technology for the construction industry.
Article published in April 2011