Making Sense of Mass Timber

Every so often, news about a mass timber building project is announced. The information about the said project might discuss the product’s sustainability, aesthetics and other advantages. However, what might be missing from the announcement is what mass timber is.

To clarify the topic, construction company Adolfson & Peterson recently brought its experts together at a round table to discuss the mass timber’s usage, benefits, challenges and outlook.

So, What is It?

Brian Carius, A&P’s Project Manager, Mountain States Region, classified mass timber as “sheets of laminated timber pressed together with a large compression machine.” The sheets typically held together with glue, are considered “glue-laminated” timber, or glulam, for short.

A&P’s Mountain States Region Preconstruction Manager Tyler Woods added that cross-laminated timber (CLT) and dowel-laminated timber (DLT) are also types of mass timber. The thing that ties these different types of laminates together is that “they’re manufactured in such a way as to create the strength and structural properties you would get with steel columns and beams,” Carius added.

What are the Benefits?

The central mass timber benefit is its sustainability. According to A&P’s Project Executive Midwest Region Patrick Sims, “sustainability” means that “the materials don’t leach as much carbon into the atmosphere. Plus, they’re a renewable resource.”

Woods also noted that manufacturing mass timber materials is sustainable, requiring “equipment to cut down the trees, a sawmill and nothing more.” Additionally, many manufacturers replace the wood they harvest, planting new trees for the ones they cut down, Woods said.

Other benefits of the material include the following:

• Less on-site construction time. “The actual installation of mass timber is pretty straightforward,” said Will Pender, A&P’s President, Gulf State Region. “It can take less time than a standard steel or concrete build.”

• More flexibility. Pender pointed out that design originality is another positive of mass timber material. “You’re not creating a cookie-cutter building, but one that has character and is unique,” he said.

• Some savings on finish costs. According to Woods, mass timber can reduce finish costs, like those on drywall or ACT. “The mass timber is your finished product,” he said.

How About the Challenges?

The roundtable participants cautioned that developers should consider the following before considering mass timber for building.

• Longer timeline. Though mass timber arrives at a site ready to install, the prep work requires more time. “ Mass timber manufacturers, on average, generally require 45 weeks from the time they’re awarded the job until the product shows up on site,” Sims said. Additionally, while finish-out costs might be less with mass timber, Woods noted that using mass timber can be more expensive than other materials.

• Zero room for errors. Once the mass timber build starts, making changes can be extremely difficult and costly. “There’s no margin for error,” Carius explained. “If something’s off even an inch or so, it throws everything else off.

• Workforce specialization. Sims explained that a successful mass timber build is one with mass timber-experienced trade partners and engineers. “Projects have fallen behind or suffered cost overruns because the personnel involved had no mass timber experience,” he added.

What’s the Outlook?

As the construction industry looks toward the 2030 net-zero goals, the experts felt that mass timber use could increase for ground-up and renovation projects. Sims said the growth could also focus on hybrid mass timber projects, including traditional materials like cement and steel.