We’ll build skyscrapers out of wood. And do the planet some good….

Nature reveals the new growth of ambitious plans to cool the planet with wooden skyscrapers:

Constructed almost entirely from timber in 2014, the 8-storey, 30-metre building is among the tallest modern wooden structures in the world. But it is more than an architectural marvel. As the home of the Wood Innovation and Design Centre at the University of Northern British Columbia (UNBC), it is also an incubator for wooden buildings of the future — and a herald for a movement that could help to tackle global warming.

The building is less like a log cabin and more like a layered cake, constructed from wooden planks glued and pressed together, precision cut by factory lasers and then assembled on site. All told, the university avoided the release of more than 400 tonnes of carbon dioxide by eschewing energy-intensive concrete and steel, and the building locks up a further 1,100 tonnes of CO2 that was harvested from the atmosphere by British Columbian trees. In total, that’s enough to offset the emissions from 160 households for a year.

By substituting concrete and steel with wood from sustainably managed forests, the building industry could curb up to 31% of global carbon emissions, according to research1 by Chad Oliver, a forest ecologist at Yale University in New Haven, Connecticut.

The renaissance in tall wooden buildings is already under way. Norway set a world height record in late 2015 with a 52.8-metre tower block; that was edged out in September 2016 by a 53-metre student dormitory at the University of British Columbia in Vancouver. This year, Austria will take the lead with the 84-metre HoHo building in Vienna, comprising a hotel, apartments and offices. The United States saw its first tall wooden building go up in Minneapolis, Minnesota, in 2016, and others are in the works in Portland, Oregon, and in New York City.

Kilogram for kilogram, wood is stronger than both steel and concrete, and wooden buildings are generally good at withstanding earthquakes. But wood has developed a bad reputation over the centuries, because of catastrophic blazes that levelled cities such as London, New York and Chicago before modern fire-suppression strategies emerged. In fact, in case of fire wood maintains its structurally integrity much better than the non-flammable alternatives favoured by modern building codes. It chars at a predictable rate, and doesn’t melt like steel or weaken like concrete. “The fact that it actually can withstand fire better than steel took a long time for people to realize,” says Guido Wimmers, who chairs a master’s programme in wood engineering at UNBC.

By some accounts, the modern era of tall wooden buildings began 20 years ago, with a simple experiment at the Technical University of Graz in Austria. Researchers glued layers of standard planks perpendicular to each other, and discovered that alternating the direction of the grain effectively negated the imperfections and weaknesses in any given plank. The result, known as cross-laminated timber, is a strong and lightweight wood panel that puts conventional plywood to shame. It can be made as large as desired and cut with sub-millimetre precision at the factory, which speeds up construction and reduces waste. And given the strength of these panels, there’s no theoretical limit to how high wooden buildings can grow. “It transforms wood from a suburban material to a very urban material,” says Michael Green, the Vancouver-based architect behind UNBC’s design centre, and a leading advocate for wooden construction.

Builders in Europe still rely mostly on concrete and steel: a 2010 Finnish government report estimated that a mere 4% increase in annual wood use in construction throughout Europe would avoid 150 million tonnes of carbon emissions, almost as much as the Netherlands emits each year.

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