By Meghan Hall
With rapidly rising construction costs, developers and project managers are constantly looking for innovative new ways to save money, often turning an eye to the latest and most advanced technologies to do so. However, some experts in the industry are also looking at ways to use one of the world’s oldest and most basic building material: wood. Building with mass timber — a process in which the primary load-bearing structure is made of solid or engineered wood — as opposed to concrete or steel, has shown potential to save developers both time and money.
“In a way heavy timber construction goes back centuries,” said William Silva, director of project development at San Francisco-based Swinerton, a national construction firm. “It’s really an older building type that was left behind, and what’s happening now is that heavy timber is being implemented in a different way.”
Silva was just one of several panel members to speak on the subject at a Swinerton-hosted event titled “Libations and Lumber” at the end of October 2018 in San Francisco, where a panel of experts explored the unique benefits building with mass timber as well as how the product’s evolution has brought it back into the building spotlight.
Mass timber has been widely used in Europe in the past decades, but it has only recently made a foray into the United States and Canadian construction market, which has long relied on stick frame construction for smaller scale buildings and what is perceived as sturdier materials such as steel and concrete for taller projects.
“What’s exciting about mass timber is it brings the opportunity back to build at a bigger scale,” said Rebecca Holt, a senior sustainable building advisor and associate at research-based architecture and design firm Perkins + Will. “That can really transform the built environment in so many different ways.” Holt also served on the Libations and Lumber panel alongside Silva.
Both Silva and Holt acknowledge that U.S. building code and the construction industry’s wariness to adapt to new modes of construction as the primary reasons why mass timber has not taken hold in the United States. Many building codes do not allow for the construction of mass timber buildings over six stories, although some states such as Oregon have passed state-wide alternative methods for new developments. Silva speculates that California may soon follow suit.
“People are preparing the paper for California building officials to provide context for jurisdictions issuing permits,” explained Silva. “This is encouraging, because it makes it easier to have a discussion. We will sit down with a client at the initial stages and have a discussion about mass timber and where they are in the knowledge cycle and its appropriateness for and applicability to the project.”
In May, Governor Jerry Brown issued an executive order that recommended the adoption of this material into the California building code. In September 2018, a bill was presented to the California State Legislature that, if passed, would encourage state agencies to collaborate with a variety of groups on mass timber workforce training and job creation.
For now though, Holt emphasized that most builders and developers are using mass timbers in ways that fit within existing code regulations.
“I think everybody is trying to work within the code and testing what we have,” explained Holt. “There is a lot of emphasis on being the tallest, and we’d all like to have that claim, but there is so much opportunity within the limitations that we have now.”
Even now, there are benefits to building with mass timber. According to Swinerton, using the material can expedite the building process by several months and save developers up to four percent in construction costs. Holt was more reluctant to state a hard number for potential time and money, stating that it usually depended on the size and scale of the project. Regardless, Holt said any savings makes it easier to convince developers of the merits of mass timber.
“We saw a cost material savings on one project of about $180,000; that’s not a ton,” explained Holt. “But it was still a savings. And then it was an easy sell to our client.”
There is, however, one a set of benefits that both Holt and Silva agreed make a difference and emphasized: precision, durability, sustainability.
Mass timber is fire resistant compared to regular lightwood frames, and with virtual design and prefabricated panels, mass timber is precise to a sixteenth of an inch. The precision creates safer, more efficient buildings, while the production of mass timber produces a lighter carbon footprint than steel or cement structures do. Engineered wood products have also produced structures with the potential to be just as intrinsically strong as cement or steel.
Holt described the perks of mass timber as an array of “complimentary performance benefits.”
“Mass timber offers so many perks in terms of sustainability and long-term impact,” said Holt. “It’s something that we can’t ignore and need to facilitate in the design and construction industry.”
For now, Silva and Holt agree that educating real estate professionals about the merits of mass timber is the first step to overcoming perceptions of risk, something that was apparent in the questions asked by audience participants at Swinerton’s event in October 2018.
“The engineer and construction side of our industry tends to resist the implementation of new processes or ideas, and so it still really takes effort to do something in a new way that has better sustainable outcomes and a lower cost,” said Silva.
Yet for Holt, the emphasis is clear and simple: “Let’s build with more wood!”