Wood highrises designed in B.C. are sustainable and safe

The search for ways to build greener, more energy-efficient buildings has triggered a 21st century version of the old skyscraper race, but these contestants aren't made of concrete and steel.

This week'sGlobe Conference on sustainability in Vancouver will hear how somemunicipalities,including two B.C. cities,are pushing theboundaries of building highwithwood.

"Whywood? Woodis sustainable. It's a renewableresource," said the University of British Columbia'sJohn Metras, standing in front ofwhat will soon be the tallest building of its kind.

The future site ofUBC's18-floorBrockCommons student residence is a hiveof activity on the campus these days.

When it's completed in 2017, it will be one of the tallest buildings in the world made mostly of wood, UBC says.

Woodis still slightly more expensive than concrete andsteel, but UBC says there's another benefit. Not only dowoodbuildings create fewer greenhouse gas emissions,they actually store carbon dioxideas well.

"A building like this, the calculation we've done, is theequivalentof taking 480 cars off the road for a year," said Metras.

"This is really the evolution ofwoodstructures."

Wood construction growing worldwide

In Japan,Australia, and all over Europe,engineers are using morewoodto reduce thehigh greenhouse gas emissions created duringconcrete construction.

New wood engineering technologyand super-strong bondingmeans it's possible to create sheets of plywood-likepanelsthat can approximate the strength of steel.

"This is the first new way to build a skyscraper in a centuryand our building codes just didn't imagineit would come up," saidVancouver architect Michael Green.

Green is a world leader in wood building design, and the architect of the tallest contemporary wood building in North America, the Wood Innovation and Design Centre in Prince George, B.C.

The eight-storeybuilding was completed in 2014using wood and wood-engineered products from around B.C.

"These buildings have to perform to the same standardsas steel and concrete, and we know they can," said Green.

"By saying we are going tall, it's a chance to expand ourimagination and open up a conversation that wasn'thappening."

Green's company is also on the cutting edge of wood highrise construction in Europe, where he's proposed what would be the largest wood-supported tower on earth, a 35-storeyskyscraper in Paris.

"The game changer is new, advanced wood products," said Green.

"We used to cut down big trees and use big pieces of wood. Now we're cutting down smaller trees, gluing them together and making them incredibly strong, so technically we can build extremely tall," he said.

"We've done technical studies that you can rebuild the Empire State Building in wood,110 storeys tall. It actually is possible."

Overcomingfire risks

The risk of firehasbeen an enormousproblem for those trying to build taller withwood.

In the 1800s,after a large fire in London and the three-day blaze that destroyedmuch of Chicago,woodwasshunned for tall structures, and the perception that wood buildings were unsafe became a barrier to innovation.

But Green saystechnologyisovercomingthat too, especially by using massive pieces of wood, which he says are massively resistant to fire and also safe in earthquakes.

"They burn very, veryslowly and char and insulate themselves becauseof their size," said Green.

"Most Canadians live in wood homes. Most Canadians don't return home from work wondering if their home is still there or has burned down, because we've learned over the last 30 years how to make homes fire-safe and now these large buildings[are]fire-safe."

The majority ofCanadian building codes still limitwoodstructures tofour or six storeys,but increasingly planners are lookingat thewoodinnovations and granting exceptions.

Green says it's an acknowledgement that ever-taller wooden buildingsmay be part of the answer to climate change.

"We talk about energy and the important shift to renewables. The same conversation is happening in buildings."