Tall timber makes sustainable high-rises

A push from the United States to build skyscrapers out of wood could see New Zealand’s sustainable forestry industry become our next big export star – and future generations living, not quite in the trees, but in towering timber apartments.

At a meeting in March hosted by the White House, the US Department of Agriculture announced a $2 million competition to promote high-rise wood demonstration projects. Currently almost all global construction of mid to high-rise buildings uses concrete and steel, which are both big climate change polluters, releasing vast amounts of CO₂ in their manufacture.

However, the USDA wants to tackle that problem by shifting to sustainable wood-based buildings. Trees trap and store CO₂ as they grow, so using timber in construction is a smart way to pull the greenhouse gas out of the air, where it warms the earth, and lock it away indefinitely.

Traditionally wood has been seen as too weak for larger buildings, but new techniques for compressing timber into strong beams from multiple slabs look promising; in much the same way as a strong bungee cord is created out of many weaker strands of elastic, larger, stronger supports can be made by combining multiple strands of timber. This also has the benefit of locking away more carbon.

Already several high-profile tall wooden buildings are being planned or built around the world as forward-thinking architects look to timber as the material of the future. A nine story-high wooden tower will be completed in Vancouver this year, while the eVolo architecture magazine skyscraper design prize this year went to a Korean-inspired wooden tower that doesn't need a single nail.

See Michael Green TED talk to learn more.