Laminated products reduce fire risk
Last updated 5/19/2022 at 3:15pm
Wood buildings are making a comeback in the Pacific Northwest thanks to new laminated timber products. Even very large buildings are now constructed with laminated beams and are successfully competing with steel and concrete building materials.
For example, the University of British Columbia, Vancouver, is home to one of the world’s tallest “cross laminated timber” buildings. Brock Commons, a student residence, is 174 feet high. The 18-story dorm houses more than 400 students.
Cross-laminated timber has many benefits. It is fire-resistant, stronger than conventional timber, reduces atmospheric carbon, offers more flexibility for seismic movement, and, is capable of reviving depressed economies in Washington’s rural timber communities.
Sometimes described as “plywood on steroids,” cross laminated timber (CLT) was developed in Europe in the 1990s and is widely used throughout the U.K., Australia, Canada and Japan.
Using CLT reduces construction costs by 50 percent and speeds up building times by as much as 65 percent. Because it’s a lighter material, CLT requires smaller and less expensive foundations. Panels can be quickly and efficiently assembled on site, which reduces construction cost, labor and the amount of trucks, noise and neighborhood disruption.
CLT not only emits less carbon dioxide during the manufacturing but finished wooden buildings help sequester existing carbon for a longer period. Buildings made with CLT for structural applications result in around a 25 to 30 percent reduction in global warming potential compared to a similar building built with traditional materials, UW magazine reported.
The added benefit is CLT milling provides a market for thinned trees---materials if left in the woods constitutes a giant fire hazard. That translates into needed rural jobs and a useful product instead of scorched earth.
On the Colville National Forest in northeast Washington, the U.S. Forest Service’s funding was insufficient to thin densely packet timber stands until a broad-base group called A to Z Collaborative formed. It is working collection of conservationists, local government, business leaders, and foresters which agreed upon a 54,000 acre forest restoration project.
After an exhaustive environmental review, the Forest Service contracted with Vaagen Brothers Lumber, a fourth-generation Washington timber company. Vaagen expanded its operations in Colville to produce cross-laminated timber.
Other Washington-based CLT manufacturers also see strong demand. Mass timber manufacturers in Oregon and British Columbia report full shifts.
A study published in 2016 estimated annual demand in the Pacific Northwest of 6.6 million cubic feet by 2035 could support four small to midsize CLT plants, each producing one to two million cubic feet per year.
Having an ample log supply is key to sustaining CLT manufacturing.
In the Lake Chelan area, community leaders are working with state and federal forest managers to emulate the Colville cooperative program. North Central Washington is wildfire prone and the bulk of the forests are managed by the Forest Service.
Since 2001, a portion of 53 large wildfires exceeded 1,000 acres in Chelan County. At the same time, combustible material, including overcrowded young trees and understory vegetation, has increased, mostly as a result of U.S. Forest Service policies to suppress forest fires, to reduce thinning and logging, and to limit prescribed burns.
Unfortunately, sawmills in north central Washington have disappeared as the bottom dropped out of the Forest Service timber sales program. A new sawmill/CLT Plant is under consideration to mill thinning, but it will require 100 log truck loads of small-diameter logs per day to have an adequate supply of logs from thinning federal forests.
The key to reducing wildfire risk and expanding CLT manufacturing is a reliable and steady supply of thinned trees. Without logs, there forest fuels will accumulate and mills have no raw materials.
— Don C. Brunell is a business analyst, writer and columnist. He can be contacted at [email protected].