MICHAEL GREEN ARTCHITECT DESIGNS WOOD TOWERS
When the Empire State Building was completed in New York City in 1931, it was the tallest building in the world. The 443.2-metre, 102-storey tower has 2.2 million square feet of office space and its construction materials included 57,000 tons of steel and 47,492 cubic metres of concrete.
Nowadays, it’s well known that the production of concrete and steel, particularly if it’s done with coal, generates enormous greenhouse gases and is a major contributor to the climate crisis. But could a structure the size of the Empire State Building be built of wood, which is a far more sustainable and renewable material? Vancouver-based Michael Green Architecture and a Finnish company, Metsä Wood, tried to answer that question in 2015.
“We did the analysis and the engineering with our partners with Equilibrium [Consulting] here in Vancouver and determined you could,” Michael Green told the Georgia Straight during an interview in his Cordova Street office. “It’s not so much that you should build 102 storeys in wood. But when people start to get used to the idea that you could, it means they get a lot more comfortable with 16 storeys and lower buildings in wood.”
For 12 years, Green has been advocating far greater use of wood in construction of large buildings to reduce society’s environmental footprint and to promote value-added jobs in B.C. In Minneapolis, his firm designed a seven-storey building occupied by Amazon. He said his firm has been invited to design buildings of 12, 18, and even 34 storeys in other cities, mostly made of wood.
“We have a brand-new project in New York City,” he said. “We have a brand-new project in Chicago, and three or four projects in Paris.”
Buildings are responsible for a majority of greenhouse-gas emissions in Vancouver, mostly through the use of natural gas and electricity. Across B.C., buildings were responsible for 11 percent in 2015. Yet according to Green, Vancouver has been slow to adopt the idea of tall wood-frame buildings even as it pursues the title of the world’s greenest city.
“This is an idea that we started,” Green noted. “I authored the original concepts on tall wood. It’s a Vancouver-born idea that now is being implemented in New York, Chicago, and Minneapolis. But we don’t have it here. It’s time.”
He pointed out that Paris held an innovation competition last year to develop environmentally responsible buildings on 21 sites. According to Green, 17 of the winning bids were for heavy timber wood structures. He credited the mayor, Anne Hidalgo, for making sustainable buildings a central priority in the wake of the COP21 United Nations climate conference held in her city in 2015.
“Paris said ‘We’re going to put our money where our mouth is,’ ” the architect said. “Right now, Vancouver is not doing that.”
Green is also offering advice to the office of Oregon governor Kate Brown on promoting more tall wood buildings in her state. He and architect Jim Taggart have coauthored a soon-to-be-released new book, Tall Wood Buildings, which will provide 13 case studies of wood buildings around the world.
Green emphasized the importance of not thinking of wood skyscrapers as being built with two-by-fours. “It’s really all engineered wood, so it’s glued together in different ways,” he said.
Then he knocked on a huge wooden table in his office, which was created from jumbo plywood engineered in Golden, B.C., made into a stunningly sturdy and thick surface. “It’s very strong,” he noted.
He added that any 102-storey wood building would still have a concrete base, as well as concrete below the earth. But above the surface, it would be almost all wood, including hollow vertical wood columns. Running up the middle of these columns would be steel cables that would be tied into the concrete base to provide the appropriate level of tension and maintain stability.
“All of the weight is carried by the wood,” Green stated.
He said the key to greener buildings is cutting back on the use of toxic materials. “You want to reduce the bad stuff and increase the good stuff. The good stuff should be natural. It should be renewable. It should be low- energy. It should be low-carbon.”
Green’s interest in environmental issues goes back a long way. He was born in the Nunavut community of Baker Lake, where his father served as a senior federal administrator for what was then called the Department of Indian and Northern Affairs. An avid outdoorsman, Green has witnessed glaciers recede over time and even travelled to the Antarctic on a kayaking expedition with his son.
“We paddled next to glaciers that are falling into the ocean,” he recalled.
He cited several reasons why tall wood buildings aren’t being constructed in Vancouver. Part of the reason is the building code. Another is the higher cost of constructing environmentally sustainable, woodframe skyscrapers when B.C. has relatively low energy prices.
“If you can measure through a lifecycle analysis that says this is truly a better-performing building, you should get a tax break or a density bonus,” Green said. “There are different levers that the city could actually use to promote these kinds of ideas. I think it’s high time they did.”