Though mass timber has existed in various forms for centuries, developers have only recently realized its usefulness for commercial real estate projects. Despite its growing appeal, the mass timber concept remains confusing, generating incorrect information about its use, benefits and challenges.
To help counteract the confusion, Adolfson & Peterson Construction recently brought together its mass timber experts, who provided their honest viewpoints about advantages, challenges and outlook.
The roundtable participants included:
Will Pender: I think we first need to clear up the misunderstanding many people have about mass timber construction. People might confuse “mass timber” with “stick frame.” Mass timber, as a product and process, differs from the typical wood frames used to build homes or apartment buildings.
Brian Carius: That’s correct. The simple definition is mass timber consists of sheets of laminated timber pressed together with a large compression machine. These sheets are typically held together with glue, so they’re technically considered glue-laminated timber (glulam).
Tyler Woods: The term mass timber is also often confused with CLT (cross-laminated timber) or DLT (dowel-laminated timber). Just like glulam, CLT and DLT are mass timber categories. For example, DLT is lumber held together with hardwood dowels rather than glue. CLT is held together with glue, but it’s a cross-laminate, meaning timber sheets are laid out with wood grain going in one direction.
Brian Carius: The one thing all these materials have in common—CLT, DLT and glulam—is they’re manufactured in such a way as to create the strength and structural properties you would get with steel columns and beams. So, yes; that’s a big difference from the wood frames used to build single-family homes.
Tyler Woods: Adding to this, product receiving a mass timber designation depends on the amount of timber used in a build. For example, a project might have wood-and-glue laminate components. But that doesn’t necessarily make it mass timber. It becomes mass timber when the material takes on a building’s entire structural load.
Will Pender: It’s also a product that’s been around for a few hundred years.
Patrick Sims: Right. Timber as a building material has been around for centuries, and I think the term mass timber was first used in the 1800s.
Tyler Woods: In the early days, though, mass timber was primarily nail-laminated timber (NLT). This involved taking a bunch of two-by-fours, or three-by-sixes at that time, and driving nails into them to create floor planks.
Brian Carius: Another thing a lot of people don’t know is the lifespan of mass timber.
Patrick Sims: I’d say at least 75 to 100 years. For example, in Duluth, Minnesota, there’s a building in Canal Park that’s now a brewery. It was built in the late 1800s from mass timber. Of course, it’s been repurposed a couple of times, but that structure proves mass timber’s strength and lifespan.
Tyler Woods: Speaking of which, the use of mass timber had died down for a bit, but in the early 1900s, it resurged in Europe. In the late 20th century, around the 1980s or so, California and Oregon started showing interest in the material and the process. These days, with an emphasis on decarbonization and sustainability, mass timber interest has increased.
Will Pender: A key positive is how the actual installation of mass timber is pretty straightforward; it can take less time than a standard steel or concrete build.
Tyler Woods: Yes. I think the national average is about an 18% reduction in the construction schedule. But you need to be careful with that number because that’s only once the material gets to the site and is put into place. That doesn’t count the overall scheduling time from the manufacturing part of the process to completion.
Patrick Sims: The manufacturing and other timelines are much longer with mass timber versus building with other materials. Mass timber manufacturers, on average, generally require 45 weeks from the time they’re awarded the job until the product shows up on site. We’re currently working on a mass timber community center in North Dakota. We had the vendor under contract for that project in late 2023, and the product started arriving on the site in August 2024.
Brian Carius: Making changes in the field on a mass timber project can present challenges from a structural perspective. Everything needs to be extremely well-coordinated from the very beginning. We built the Foothills Golf Course Clubhouse (in Denver), which was steel on the lower level, transitioning to mass timber above. We had to ensure the Kerf plates were perfectly positioned so the columns could be easily placed. There’s no margin for error. If that’s off even an inch or so, it throws everything else off, and you need a structural engineer to fix things. Proper quality assurance was crucial.
Patrick Sims: You also need to ensure the structural engineer has worked with mass timber. In fact, you need to find trade partners knowledgeable in mass timber before other trades are brought on board. Projects have fallen behind or suffered cost overruns because the personnel involved had no mass timber experience.
Tyler Woods: Speaking of which, clients shouldn’t go into a mass timber project with the belief that it’s less expensive than your standard steel or concrete build. For example, PlatteFifteen (a CLT/mass timber office building in Denver) carried a 25% premium on raw material costs. Now, if a project is carefully managed, with no room for error, the cost gap could theoretically even out due to the speed at which the product is assembled once on-site. But overall, your client would pay a premium for mass timber.
Will Pender: On the other hand, there’s more design flexibility with mass timber and additional design originality. You’re not creating a cookie-cutter building, but one that has character and is unique.
Tyler Woods: Definitely. The aesthetics are great—mass timber beats out steel or concrete for looks every time. And you actually save money on finish costs like drywall or ACT because the mass timber is your finished product.
Patrick Sims: Still, from a use-case perspective, mass timber isn’t for everyone. I think you’re seeing more visual-type buildings make use of this, like churches, apartments or even office buildings. Typically, it would be a building wanting to achieve some type of aesthetic or design, and wood is the way to go.
Tyler Woods: We’re also starting to see more acceptance and use in the higher education space. One project we’re interested in is a university’s mass timber lab research building. I think as the younger generation comes into leadership positions and supports sustainability, we’ll see more mass timber projects come to fruition.
Brian Carius: But there are certain considerations to consider before going all-in with a mass timber project. We mentioned some of those – usage, construction personnel, logistics. Others might include state or municipal regulations.
Patrick Sims: Absolutely. Some municipalities like the idea of more mass-timber buildings. But there are restrictions. For example, we’re seeing more mass timber projects in Minnesota, but the biggest issue right now is height restrictions in many municipalities.
Will Pender: You also make a good point on the state issue. In Minnesota and Colorado, demand for the product seems to be growing, not so much in Texas. There’s a 242,300-square-foot mass-timber under construction in Frisco, a far north suburb of Dallas. But that building is more of an anomaly in Texas, given what tenants are willing to pay for space. They likely won’t want to pay $75 a square foot when they can go to the office building next door and pay $45 a square foot.
Tyler Woods: To consider mass timber’s sustainability, it’s a good idea to see what goes into its manufacture and use. Let’s put it this way: a lot of carbon emissions are involved when working with steel or concrete manufacturing and construction.
Patrick Sims: That’s not the case with mass timber products. The materials don’t leach as much carbon into the atmosphere. Plus, they’re a renewable resource.
Tyler Woods: That’s right. The main activity of mass timber manufacture is cutting down timber strands and compressing them into prefab walls or floors. That requires equipment to cut down the trees, a sawmill and nothing more. Also, many manufacturers replace what they harvest. One manufacturer, Nordic Structures in Quebec, has its own forest – or farms, as they call them. Every time they cut down a tree, they immediately replant one, which helps with mass timber’s carbon-positive agenda. They use black spruce pine, which matures very quickly.
Another thought is that those trees in the woods have absorbed carbon from the atmosphere thanks to photosynthesis. As it’s milled into lumber and converted into mass timber, carbon remains in the wood rather than being released into the atmosphere, which is what can happen when producing steel or concrete.
Brian Carius: From my perspective, the only questionable concern from a sustainability point of view is the logistics of bringing the product to the site. Unlike steel or concrete manufacturers, which are everywhere, only a certain number of mass timber manufacturing plants exist, with most of them in Canada. Because of this, the product often travels a long way to the building site.
Tyler Woods: There’s also additional preparation to working with mass timber—you want to make it weather-resistant. With a glulam, the sides are finished, so that wouldn’t be an issue. But water can seep and wick through the tops and bottoms of those glulam columns and beams before they’re fully assembled, so a cost would be associated with protecting the material. Then again, you go to Vancouver, and their mass timber projects are getting rained and snowed on all day, and it doesn’t seem to be a problem.
Patrick Sims: Mass timber’s durability depends on the structure’s design and ability to protect the mass timber. For instance, providing sloping to a structure can ensure that water or moisture will not be allowed to accumulate and penetrate the wood, which adds to the longevity of mass timber. Also, a lot of questions come from the insurance side of projects related to mass timber, especially with fire ratings. Those are interesting conversations, but in fact, the fire rating for mass timber is comparable to other fire-rated materials.
Will Pender: Mass timber product also comes prefabricated. The walls, roofs, floors and so on are manufactured off-site, wrapped, then delivered. It makes installation less complex once the components arrive on-site. They’re simply bolted together.
Tyler Woods: That’s another sustainability advantage. Fewer workers are needed to put a mass timber project together. This means fewer cars are driven to a site and less noise and dust. When we built PlatteFifteen (a CLT/mass timber office building in Denver), we had six installers from the Nordic team building it. When you have a turnkey concrete job, you’ll probably have hundreds of partners on-site.
Brian Carius: Related to sustainability. I think as the construction industry works toward meeting the 2030 net-zero goals, the design-build community will look toward alternative, carbon-neutral materials for ground-up and renovation projects. This is where mass timber usage could ramp up.
Tyler Woods: Some of that also depends on the costs involved with mass timber usage. I can tell you from when we built PlatteFifteen to today, the cost delta has gotten closer. But it’s still there. As more mass timber manufacturing plants open and more sustainability efforts are emphasized, I agree with Brian that more mass timber projects will come online.
Patrick Sims: Also, I think the emphasis and growth will be on hybrid mass timber projects rather than strict mass timber buildings. The North Dakota community center we’re working on is a mix of concrete, steel and wood. I think there will be more push for those types of projects. Overall, the move from mass timber from outlier to mainstream usage is on its way.
Foothills Golf Course Clubhouse, Denver, CO