Wood Structures Could Reduce Global Carbon by Almost a Third
October 6, 2014
What would happen if we replaced all concrete, steel, and brick with wood products in new construction? A whole lot of good, suggests a new study from researchers at the Yale School of Forestry & Environmental Studies.
The analysis, “Carbon, Fossil Fuel, and Biodiversity Mitigation With Wood and Forests,” published in the Journal of Sustainable Forestry, concludes that total replacement would result in a 14%–31% reduction in global greenhouse gas emissions, a 12%–19% reduction in global fossil-fuel consumption, and a likely increase in biodiversity.
The ranges are so wide because impacts vary according to how trees are harvested and how efficiently the forestry products are used, the authors explain, pointing to cross-laminated timber as an efficient use of wood (see Engineering a Wood Revolution). Most of the savings in carbon would come from avoided emissions; some of the fossil-fuel savings would come from direct burning of scrap wood for energy. The impact of sequestering carbon in the wood itself—whether in a building or in a forest—is small by comparison.
Projected increases in biodiversity would result from “active management,” the authors argue, explaining that more-open forest structures tend to support the greatest number of species. Given the fragmented state of the world’s forests, it may be “prudent” to manage them in a way that creates more diversity rather than waiting for natural processes to take back over, they argue, adding that “in the process of this active management, some trees can be harvested and utilized.”
The researchers recommend that incentive programs and building codes should encourage the use of sustainably harvested wood in place of concrete and steel, and that forestry programs should account for the fact that carbon sequestration in forests may be “counterproductive” if it results in more concrete and steel production.