CALIFORNIA – In February 2020, USDA Forest Service representatives from the Pacific Southwest Region participated in two tours of “mass timber” construction sites in the San Francisco Bay Area. The tours were organized by WoodWorks, an organization that provides outreach and technical assistance to architects, engineers, contractors and developers to increase the use of wood in construction.
Mass timber is a general term for large wood panels and beams, often made with lumber and sometimes veneer, glued together in ways that increase strength and design flexibility. Mass timber products are strong enough to replace concrete and steel in many building projects, and the trend of using wood in tall buildings is increasing worldwide.
Tour participants were primarily architects, developers and construction company staff who were interested not only in the design, permitting, and economics, but also in some cases where the wood came from, and how it was being grown and harvested.
California currently leads the country in terms of the number of planned and completed construction projects involving mass timber. The three construction sites visited by tour participants spanned over 550,000-square-feet and ranged between four to five stories. One of the buildings visited was also the first multi-story mass plywood building in the United States.
Project construction managers emphasized that for small sites located in expensive urban markets, such as San Francisco, mass timber works financially because buildings can be erected faster than those built using traditional building materials. This greatly decreases urban traffic disruption and construction time where rates for skilled trades, such as carpenters and electricians, are among the highest in the country. An architectural engineer involved in a couple of the projects visited commented that it takes much more pre-planning and coordination, but the cost savings are well worth it.
“We’ve watched the mass timber trend gain tremendous momentum over the past few years,” said Janelle Leafblad, WoodWorks’ regional director in Northern California. “The interest is definitely there—with reasons ranging from sustainability to the unique aesthetic of exposed wood that can translate into leasing velocity and market differentiation—and we’re providing the education and project support that are necessary precursors to widespread adoption.”
Use of mass timber in construction is likely to increase as building codes begin to allow mass timber in buildings up to 18 stories tall. In addition to the forest management benefits that come with better markets for wood products, mass timber has the added benefit of replacing concrete and steel in some buildings, reducing the carbon footprint of construction. Sustainability is very important to the users of mass timber, and the Forest Service can help answer some common questions from architects, engineers, developers and others such as “where does the wood come from?” and “is it sustainable?”
The partnership between the Forest Service and industry has potential to grow markets for Forest Service timber while increasing the sustainability of the urban built environment, exemplifying the motto of Caring for the Land and Serving People.