If environmentally-minded architects have their way, more mid and high rise buildings will be constructed with wood instead of concrete and steel. An article in CNN's Eco Solutions coverage asks, Can wooden skyscrapers transform concrete jungles?
Architect Michael Green is designing a 30 story building constructed with wood in Vancouver and advocates for more tall wood buildings:
"We think we can go higher than 30 stories," says Green. "We stopped exploring wood around 100 years ago (with the advent of steel and concrete); now we're looking at a whole new system using mass timber products." Green says that the modern wood materials have been around for around 20 years, but until recently they've been quite niche or used only in low-rise buildings. What has changed is the way in which architects and builders are thinking about using wood. "The real change came when we started thinking about climate change. Steel and concrete are great but not environmentally friendly," he says.
The modern wood materials that Green mentions are laminated strand lumber (a composite of wood strands glued together) and cross-laminated timber (layers of wood fused together at right angles to each other). Since the newly developed materials use wood fibers, they eliminate the need for cutting down large trees. Sourcing wood from sustainably managed forests also creates a more environmentally sensitive process.
As for concerns of fire risk, large timbers are naturally fire-resistant and perform better in fire than structural steel. Timbers form an insulating and fireproof layer of char that also protects the structural integrity.
Of course, as Green points out, any building material has to be cost effective to catch on in a big way. His firm's research and designs of tall wood structures (pdf here) are offered for public use via a Creative Commons license.
Image: Michael Green Architects