Mass timber construction is gaining ground in North America, with the frequent justification that it reduces embodied carbon (the upfront greenhouse gas emissions associated with manufacture and transportation of materials) when compared with concrete or steel. But not all wood products are created equal when it comes to carbon emissions, according to the newly created Climate-Smart Wood Group.
The goal of the organization is “to help building project teams successfully identify, access, and use climate-smart wood. The effort is jointly managed by the Forest Stewardship Council–US (FSC–US), Ecotrust, and a number of other nonprofits. FSC creates voluntary standards designed to encourage environmentally and socially responsible forestry practices.
Climate-smart forestry “relies on actions such as selective harvesting, longer rotation lengths, and tight restrictions on hazardous chemicals,” according to the fact sheet. The group identifies two types of wood that qualify as climate smart: timber from FSC-certified forests, and products from restoration projects designed to “lower wildfire risk, reduce vulnerability to pests and pathogens, and increase forest diversity, resilience, and carbon storage.”
The group aims to advocate for climate-smart wood and support specification and purchasing of these products by building project teams.
Indeed increasingly, engineered wood products are challenging concrete and steel in structural applications while proffering a lower environmental footprint. Wood seems poised for a resurgence in structural applications.
Where available, wood has been the primary building material for most residential and commercial structures in North America prior to the 1900s. It was cost-effective to transport on rivers and rail, abundant (at a cost to ecosystem health, at times), inexpensive, and easy to work with. Light-frame wood construction remains popular for homes in the U.S., but with the advancement of steel and concrete use, skyscrapers went up, and timber’s popularity went down.
In the past 20 years, engineered wood technology and production methods have improved the performance of timber products, and for commercial buildings they now offer an intriguing alternative to concrete and steel in many structural applications—while offering environmental benefits.
Photo: The Richmond Olympic Oval was the site of speed-skating events during the 2010 Vancouver Olympic Games; its ceiling is made from trees killed by the mountain pine beetle and turned into engineered wood.