Mass Timber Construction: The Carbon Sequester
From the embodied carbon associated with construction materials to the operational carbon produced throughout a building’s lifecycle, the design and construction industry has the opportunity to make a big impact when it comes to carbon. Join STO Building Group’s director of sustainability, Jennifer Taranto, as she interviews two subject matter experts: David Briefel, sustainability director and design resilience leader at Gensler, and Jeff Morrow, president of J. Morrow Solutions, as they discuss the ingredients of net zero carbon buildings and how mass timber construction can fit into the equation.
Jennifer TarantoDirector of Sustainability, STO Building Group
David BriefelSustainability Director & Design Resilience Leader, Gensler
Jeff MorrowPresident, J.Morrow Solutions
Welcome to STO Building Conversations, a construction podcast powered by the STO Building Group. On today’s episode, STO Building Group’s director of sustainability, Jennifer Taranto has a conversation about net zero carbon buildings and the rise of mass timber construction with two subject matter experts: regional sustainable design leader at Gensler, David Briefel, and president of J Morrow Solutions, Jeff Morrow.
Hello, I’m Jennifer Taranto. I’m the director of sustainability here at the STO Building Group. And today we’re going to discuss a sustainability trends that have been gaining ground in our industry over the last few years, specifically net zero carbon buildings and mass timber construction. And today I’m joined by David Briefel, regional sustainable design leader at Gensler and Jeff Morrow, president of J. Morrow Solutions. Would you mind taking a moment and just introducing yourselves a little bit more. David, why don’t you go first?
Sure. My name is David Briefel and I’m a sustainability director at Gensler and we are a global architecture firm and I focus primarily as a sustainability consultant, working for clients across a variety of different paths to achieve sustainability on their projects, including strategy work, analytics work, and sometimes certifications.
So I’ve been in the construction industry for over 20 years and worked with delivering the first year energy duplex in the United States, about 11 years ago at Fort Campbell, Kentucky, and also delivered multiple CLT structures of hotels for the US Army as part of the Privatization Army Lodging agreements with the US military and the Department of Defense.
Great. So, you know, let’s start out by just setting the stage and talking about just the definition, of what can net zero mean? And for the purposes of our conversation today, we’re going to kind of narrow in on a particular component. So David, I’m going to hand it over to you. What can net zero mean?
Yeah, so I think when we talk about net zero, it’s first important to understand what we mean by net zero. And so oftentimes when our clients come to us and they say, we want a net zero project, the first question I asked back to them is net zero what? In some cases, we might be talking about net zero energy, other cases, it might be net zero water. Sometimes we talk about net zero waste, but most commonly these days, we’re talking about net zero carbon.
Yeah. Thank you. And just unpack for us a little bit about the difference between net zero energy and net zero carbon, because the two are really intertwined, but there are some fundamental differences.
Yeah, sure. So, when we talk about net zero energy, primarily we’re talking about how the building operates. And so we’re looking at the energy use in the building or operational energy. And we’re looking at ensuring that the building would be producing—in some cases, it would be entirely onsite, sometimes it’s a combination of onsite and offsite—as much energy as you would be using. And so that’s where the zero comes from. There’s a net zero energy use of that building. When you start to talk about carbon, you bring in many other elements that would include things like potentially the embodied carbon of the material that goes into the building and all the building materials. And you might also be talking about the energy sources, the type of fuels that you might be using that would contribute to that energy uses and all of that gets factored into a larger definition of carbon. And obviously for the other types of net zero, waste and water, you would be talking about the same thing. So you’re looking at essentially producing as much water as you would be consuming on the site or likewise with waste. You would be ensuring that you’re reducing the amount of waste that you’re using on the site, or diverting waste from landfills, such that you would have a net zero waste.
So net zero carbon is a bit of a bigger nut to crack. You mentioned sort of the going back to materials, even that are into the building. And we know that each one of the different fuel sources has its own carbon emissions. Some fuel sources are cleaner than others and that can all end up contributing to the overall carbon of a building. So, some other things, interestingly that, you know, when you read through industry publications, you see a bunch of different terminology that gets used. There’s carbon neutral, there’s climate positive, there’s a series of other terminology. And I know that today we’re really going to focus in on net zero carbon, but just talk a little bit about some of those other terms and what they mean.
Again, there’s a lot of terms that are thrown out. When we start talking about net zero, sometimes people are asking for a net positive or a regenerative building. Again, those would be actually contributing more to the existing site or the existing condition than what you started with. When you’re talking about carbon, you want to reduce the amount of carbon. So that’s why people start to say things like negative. And zero and carbon neutral are sort of synonymous in that you’re sort of netting out the impact of the building. Fundamentally though, all of these things, whether you’re talking about net positive, you’re talking about neutral or negative, we’re trying to do better and we’re trying to make a better impact. And usually when you’re talking about a net zero building, you’re talking about a really progressive project that’s aspirational in nature and is really trying to make great strides from an environmental perspective. And so, they’re all fundamentally trying to do the same thing. When you hear clients or you hear architects talking about achieving this type of level of project, they’re trying to make a big impact and reduce carbon significantly or improve the environmental impacts.
So David, when we talk about net zero, what are you seeing in the industry right now in terms of, is the focus on the embodied energy of the building of getting the building built or is a net carbon zero, is it being more focused on the operational efficiency and the carbon or the output of the building once it’s operational? Or is it focused on both?
Yeah, I mean, it’s a good question. I personally have been hearing a lot more about the embodied carbon question rather than the operational carbon question. And that doesn’t mean that one is more important than the other. I think operational carbon has been a hotter topic of recent because of some new advents within, and I think we’ll talk about some of the technologies, including the structural implications for embodied carbon buildings. I also think there’s been an increased amount of transparency and importance put on transparency around the materials, which allow us to be able to evaluate materials. And that’s going to be a critical part of making good strides within embodied carbon. And I think, you know, operational carbon and sort of a net zero energy side of the conversation has been a focus of the industry for years and most notably the AI 2030 commitment and trying to reduce energy in the building for a long time. And code has also made great strides with operational energy. I think the embodied energy in the embodied carbon side of the conversation is now a new focus, understanding that it has a huge implication and it really hasn’t been focused on with the same sort of scrutiny.
Right. But Jeff, you make a really good point. You know, when you’re thinking about what the ingredients are of a net zero carbon building, embodied carbon for a new building is a big piece of that. And that’s a great place where mass timber can come into play. Can you talk a little bit more about that?
Sure. One of the things that we like with mass timber is that mass timber elements are made out of wood, a renewable resource. And it’s a great opportunity to sequester carbon from the atmosphere. As the trees grow, they take the carbon dioxide out of the atmosphere. They convert it into the sugars that become eventually the fibers and lignin of the tree. And that material gets stored as carbon within the tree. And then once you harvest the tree and you can start using that for different components in your building. So one of the recent, I’m going to say technological advances, it’s been in Europe for about 25 to 30 years, and it’s really starting to make some penetrations here into the North American market and particularly the United States is starting to use mass timber and cross-laminated timber, particularly for larger buildings where instead of a hundred, 150 years ago,
when we use wood, we were just using really big trees to build our structures for big columns and big beams. Now we’re able to take smaller trees and glue the components of those smaller trees into much bigger elements that we can now use for buildings up to 18 stories tall. So we can glue small pieces of wood together to make large columns, you know, 24 inches by 24 inches by 30 or 40 feet tall. But then we can also make cross-laminated timber panels out of the smaller pieces of wood where each layer of wood is going in a different direction with the grain to give it its strength and the glues that are holding that wood together can make these panels, eight feet by 60 feet long, you know, 10 feet by 60 feet long. So, you can take these panels and start building them for either walls or floors or roof applications. It used to be before, we couldn’t grow trees big enough to do this or those large trees are now gone and now we can use a much smaller stock, that’s a strong wood and especially strong enough when you glue it all together to have really interesting buildings, using carbon as its main source.
That’s really interesting. The other thing that comes to mind is that, especially in the world of sustainability, we often play in the realm of building certifications and there’s a dizzying amount of building certifications, I think, on the market. But there are also certifications that address net zero. David, can you talk a little bit about some of those and how they compare with more established certifications, like the LEED certification?
Yeah. Well, there’s definitely a number of new certifications on the market that address the zero energy and zero carbon. I think in North America, there are three predominant certifications: LEED Zero, which is the certification that’s administered by the USGBC. You have the Zero Carbon Building Standard, which is the Canada Green Building Council. And there is the Zero Carbon certification by the Living Future Institute LFI. And there are other certifications on the market. I don’t want to ignore other ones. There are certainly others around the globe, but if you just take a look at those three certifications, there are some major differences between how they evaluate the criteria of what a zero carbon building would be. And some of them focus in on transportation like LEED Zero. Whereas the other two certifications I mentioned don’t really look into factoring in transportation. So, at the moment it is actually interesting to look across these certifications and as you’re obviously evaluating them for your projects, understand that there are some significant differences between what they use as benchmarks and how they define what constitutes a zero carbon building.
Yeah, I think that’s interesting. It’ll be even more interesting to see over time as these net zero carbon buildings become more prolific, which one of those may rise to the top. But you don’t need to have a certification in order to have a net zero building. You know, we sort of defined it for ourselves at the beginning of the call – how do offsets fit in?
Yeah. So first I think I’ll try and address a little bit about the value of certifications and the construct of a certification in that, obviously anyone can call their building a zero carbon building. There’s no rules around that. And you potentially could have a really poor performing building that uses a ton of energy and runs entirely on fossil fuels. And to actually say that it nets out with carbon, you could purchase, like you said, a number of offsets in order to get to zero to offset the amount of carbon that you’re making to the atmosphere. The offsets would be the benefit of a third-party certificate that you can purchase that shows the benefit of projects that would either sequester carbon or reduce carbon from another carbon producing activity. And so, carbon offsets are typically part of all of the definitions that are set out by the certifications, but oftentimes the certification will first limit the amount of offsets that you can use on a project. And they’ll demand a certain level of energy performance before you can use those offsets. And so that way a building that goes out and says that it’s a zero carbon building by its very nature also has to be a high performing building from an energy standpoint.
Right. So, personally, I like building certifications. I think they do sort of add that extra layer of assurance. You at least come to the table with a project or building that has a certification with an understanding of what it means, right. Rather than having a loose definition. So I appreciate that, in the world of net zero, that the same holds true. It does sound a little daunting though when you’re thinking about how do I get a new building to net zero, you know, you’re starting with a blank slate, but then you think about an existing building that seems even more daunting. Is there any low hanging fruit or any strategies that you can think of that are easy to implement, but make a pretty big impact?
Yeah. So again, going back to the certifications, I think I agree with you, there’s a lot of value to certification as a construct to help set definitions, to getting to a net zero project. But even if your project is in targeting zero carbon emissions, and you’re just trying to make really big reductions, there definitely are some things that we’ve identified as being high impact. And so, we’ve completed a bit of research recently where we, we looked at all of the materials that go into common projects that we work on from core and shell buildings and commercial and tenant interior fit outs. And so, we pile up this quantity of materials and we looked at their carbon impacts from an embodied carbon standpoint. And what we discovered is that for the core and shell buildings, the biggest offenders for carbon are the materials that you might imagine, those are structural materials.
And I think, Jeff can talk a little bit about that in terms of the alternatives from a mass timber standpoint, but from the interiors perspective, if you’re working on tenant fit out projects, it was really interesting to see that particularly when you look at the full life cycle or lifespan of a building where the amount of renovations that happen, that if you look at some of the highest offending materials in terms of their impact, things like furniture, carpet, ceiling, tile, office fronts, and some board, and some of your walls, some of the material, those ended up becoming quite large and almost comparable to your big structural materials like steel and concrete. When you look at the turn of a building over its lifespan. And so, if you’re a designer, an architect working on a potential interior project, and you’re wondering if you can make a big impact, the answer is yes. And if you just want to really simplify it, you could just focus on one of those categories that I just mentioned. So, you could really focus on furniture. Carpet today probably has the best information available in terms of the tenant interior materials that are available in the market. And so, you could really just focus on carpet on that project and ensuring that you’re selecting a low embodied carbon carpet as compared to the benchmarks and availabilities that are available to designers to select from.
I think that’s fascinating some of those interior products in particular that you mentioned, there’s sort of a grassroots push to kind of start some circularity in those markets about where can we push for reuse markets and where can we push the manufacturers to take back those products and recreate more carpet. I know the carpet industry and the ceiling tile industry, and even the gypsum wallboard industry to a certain degree have been doing this or started doing this. But I think that, especially when you’re thinking about carbon, that creating more circularity in those markets can only be beneficial long-term.
Circularity. That’s a term we haven’t really ever discussed. I mean, 10 years ago, no one even discussed the concept of what that is. And now we see that it’s gaining acceptance and moving forward. It’s fascinating to see how much the industry has changed in just a few, few short years.
Yeah, for sure. I think there’s an interesting period of seeming disruption that’s happening around those topics right now. And so they seem to be moving in the right direction and it takes a lot more exploration and a lot more appetite for people who are willing to take on reused materials and for pushing manufacturers to take their products back and remake them so that they can be used again. But you’re right. It does, it does all seem to be starting to move in the right direction. Let’s move to mass timber a little bit here. When we think of carbon, we think about some of that operational piece as well, not just the embodied piece, which we’ve touched on already. Are there energy benefits to mass timber work? Can you tell us a little bit about that?
Yeah. We found that on some of the hotels that we were building with cross laminated timber, we were using CLT walls on the exterior face, and we were using for several different applications, one for its blast resistance properties, but we also found that the thermal massing of the CLT, there was so much wood fiber that was in the panels along the entire face of the building, as well as in the floors and the roof that those panels would absorb a certain amount of thermal energy and the tightness of the panels that would reduce your opportunity for air infiltration along the exterior envelope. And then if you put the sealant on the outside of it as well, then you really reduce the opportunity for air infiltration and what we found this, that these buildings had an exceptional thermal performance. If you had wild temperature swings on the outside, it would take a long time for the temperature, to impact itself on the interior, because once the wood structure had gained a certain temperature, it didn’t really want to change from that.
Very often, we also had a building we were doing in Alabama, and we had about three weeks of a hundred degree heat. And for the longest time that building stayed cool without any air conditioning. And then, after three weeks, the building had absorbed enough heat from the sun and the ambient air that then it turned into a radiator and all of a sudden everything was hot. But one of the things is that it does have some exceptional thermal massing properties, and it works very well for a building envelope as well for your walls. I think the trend in the industry will be moving forward though, as now that the building codes have started to allow for taller buildings out of timber. I think you’re going to see a lot of office buildings and residential spaces where you may have a lot of instead of CLT for the exterior curtain wall. You’ll have more of a traditional glass curtain wall experience there that you typically see with steel and concrete structures.
You mentioned blast performance, and I know you cited some of your, um, experience at the beginning related to your work on some structures for the U.S. government, but this also dovetails pretty well with resilience, right? So, if it proves to be blast resilient, it would tend to be more resilient to severe weather events as well. Right?
Yeah. Clemson University and Texas Tech, both did some studies where they would take some two by fours and shoot them out of a cannon at 110 miles an hour into CLT wall panels to see what would happen. They thought maybe they could make for a good resilient storm shelter or the like, and what we found is on the three inch CLT wall panel, a two by four coming out of the cannon at a hundred miles an hour, it gets stuck into the wall, but wouldn’t penetrate all the way through the wall, that the wall was exceptionally strong. It didn’t break, and it would hold up very well for a tornado event where you have lots of objects flying at very high velocities. And then for our blast resistance, we also found that those buildings with CLT, they can definitely take a beating from a blast. They perform closest to concrete compared to any other material besides concrete. Reinforced concrete is above all the strongest for blast performance, but mass timber works very well far better than conventional CMU or brick veneers or metal stud or steel construction with that works very, very well. So, in buildings where you might have to have a blast resistance performance requirement, you can do that very well with mass timber.
Let’s talk about where you source mass timber materials from that. I just want to sort of highlight one of our previous discussions that you reframed this for me in a way that was unexpected, because I was sort of lamenting about getting materials from Europe for a project in the Northeast, instead of getting it from Canada, for example, but let’s unpack that a little bit more, you know, local, foreign, domestic – what’s the best play to keep carbon low?
I think the most important thing to help keep the carbon low footprint low is just to utilize mass timber where you’re sequestering the carbon. But if you’re worried about the transportation logistics, that will vary depending on where you are in the country and where you need the product, and where it is the product is coming from. North America is covered with lots of forests in different parts of the continent. And Europe also has substantial amount of force there as well. And it may sound counterintuitive that mass timber coming from Europe could have a potentially lower carbon footprint, but when a lot of these materials that are manufactured in Europe, they get loaded into a shipping container and then they’re shipped across the Atlantic. And if they’re delivered to a project that’s on the Eastern seaboard where there’s a port, especially if the projects are in the port city, there’s very limited truck travel.
And the truck travel does increase the transportation footprint from a carbon perspective. And the carbon footprint of the transportation when it’s on the boat is much, much less, and the same thing with rail. Rail is very efficient for moving large, heavy goods as well. You know, ideally if you could source the timber, your mass timber from very close to where your project is, that’s the ultimate win. Right now, we’re not there in the United States where every forest area has a CLT plant or a mass timber plant. Uh, we’re not there yet. Uh, Canada has some plants across the country, more in the Eastern and the Western parts. And then the United States, we have some manufacturing going in. We have it in Alabama, we have it in Oregon and we have it in Washington state and there a new plant will be coming online in Arkansas.
So, uh, between Alabama and Arkansas, you can cover a good bit of the Midwest and the East coast. Then you have the Pacific Northwest well covered. You have gaps in between and right now we’re, the supply chain is not caught up to that, but it’s also a factor of demand that if you have enough demand for those products in that area, you could justify the investment in the plant and start tapping into that local forest fiber source. But, you know, right now this is an organic growth for that,
Right, and with that demand too, in the creation of additional plants, you can see that it might reduce the schedule impacts too, right? So, if you’re trying to source the materials from further away, you’re going to have greater schedule impacts to get that material. Is that right?
That is correct. That’s a good point. So anytime you’re ordering material from Europe, you have to budget in the freight time for the shipping to get across the ocean, which could add anywhere from three to five weeks to that. Whereas if you order any material that’s harvested and assembled in the United States, you’re talking three, four days drive max, no matter where you are across the country.
Now this question might be a little bit in the weeds, but I’ll ask it anyway. So cross laminated timber, you mentioned it before, it’s a bunch of smaller pieces that are essentially glued together and thinking about indoor air quality of buildings and the laminates that they use, the glues that they use in order to make those outside of the U.S. obviously they have different standards. Are there any concerns there? Is there anything that we should be thinking about when we’re sourcing our timbers?
So right now, with all the glues that are used for mass timber products in North America, those glues do come from Europe. So, they are built to the same safety standards in terms of off gassing and the impact of what those glues can do. So, in that regard, they’re good. There are some different manufacturing standards, certification processes for European products versus North American products. So that when you’re looking at using mass timber materials, you need to look at your local codes to see what standards that they are willing to use.
Right. And I’m just going to back up a little bit here, because I know that sometimes we use acronyms in the world of sustainability. So Cross Laminated Timber, commonly referred to as CLT, and then there’s Glue Laminated Timber, which is commonly referred to as GLT. And there’s another right. Dowel Laminated, Timber DLT. Can you just give us a brief overview of what the difference of those three things are?
I’ll throw a fourth one in there as well as main use is called a Nail Laminated Timber, NLT. So I guess the simplest thing would be is if let’s say you looked at a two by four piece of lumber, and you took that two by four piece of lumber and you laid it down on the ground, and then you turned it so that the tall edge was up, the four inches was up. So if you took a bunch of those pieces that are in the vertical orientation, and then you stack them next to each other, and then you’ve started to put nails into them to hold them together, that would be nail laminated timber. So that every time you put a new piece onto the side, you put some nails in it to hold it to the other pieces that are next to it, and you keep adding pieces to it, and you would assemble pieces that way.
So, you’d have basically like a stack of almost like a deck of cards, but the deck of cards is on the side. If that makes sense with nails going through it. So that’s nail laminated timber. Uh, now they’ve advanced that to go to dowel laminated timber, instead of using nails to hold those pieces together. Now they’re drilling holes into the side and driving it. Typically, it’s a softwood material that you’re using for your two by fours or two by six or two by eight. And then you’re drilling a hole and you’re putting in a dowel, that’s put in at a drier moisture content than what the adjacent wood is. And as that dowel pin starts to swell up, it creates a mechanical, fastening with them without any nails. It’s just all timber connection that locks all the pieces together. So, we’ve talked about NLT and DLT, the dowel laminated timber.
So then now if you take that wood and you let’s say, you know, those were using mechanical fasteners being out of wood or nails. Now, instead of that, let’s take several of those pieces of wood. And we glue them all together and we press them. That would become glue laminated, timber, which you would typically use for columns and beams, where all the wood grains, all running in the same direction. And those pieces work very well for your beams and your column applications. The next step would then be cross-laminated timber. If you take a piece of wood and you lay it down flat on its side, and then you lay a bunch of pieces side-by-side together and all the wood pieces are going in one direction, and then you take another layer of wood pieces and you stack them crossways against the first layer, but you put a layer of glue in between, and you stack those shorter pieces along the entire length that you had on the first layer.
So now you’ve got two layers where the wood grain is going in different directions. Now you put another layer of glue on top of it, and then you put the third layer of wood alternating the glue in the other way. So, if you ever look at a sheet of plywood, that’s just like that. But normally with plywood, you’re looking at one eighth inch thick veneers, you know, very thin layers of wood glued together. So instead of plywood with eighth inch veneer is it’s normally four feet by eight feet long. Now let’s talk about you using pieces of wood that have been glued together, and you’re making these sandwiches and the layers are instead of an eighth inch thick. Now they’re an inch and a half thick, and you’re starting to build a three-ply floor panel that could be four and a half inches thick and exceptionally strong.
And it could be instead of four feet by eight feet, like a sheet of plywood, now we’re talking eight feet to 10 feet wide by up to 60 feet long, you know, you could call it a lumber sandwich. You could call it plywood on steroids, but it’s all glue that’s holding those pieces together. And then once that glue cures, you have a very strong composite product that can span some nice distances and it’s a renewable resource. And the embodied energy of that is far less than the energy expended to create steel or concrete. And then the fact that you’re also using carbon as your base material for that as a carbon sequester really makes its carbon footprint substantial compared to the more traditional steel and concrete materials.
Those are great descriptions. Thank you. I can visualize it as you describe it. So that’s nice. You know, I’m going to jump from that to cost every year. STO Building Group does an annual sustainability survey and year after year without fail cost is the biggest challenge our clients say that they face in putting forward any sustainable measures as part of their building and design practices. So, David, I might ask you to weigh in on this one, do you see net zero carbon buildings costing more? And then Jeff, if you’d follow that up by talking a little bit about mass timber and if it costs more.
Yeah. So, this is like the eternal question that we’re faced with, particularly in the sustainability world. I mean, anytime you innovate, I associate somewhat of a soft cost with doing something for the first time, but that doesn’t mean that inherently a net zero building or even a mass timber building is more costly. I think a lot of times what we see is that the buildings are priced out because people don’t necessarily understand the full implications of working with those materials or using the technologies. But over time, I think it’s been proven out that, you know, a lot of the buildings that were once associated with being a high-performing building or green building, actually, the costs of those buildings are equivalent of a fairly standard building construction. But sometimes it takes a bit of time for the market to normalize with pricing when it comes to labor and working with different materials, even if the cost of working with those materials aren’t inherently any higher.
I also think that we would be remiss when we start talking about costs. If we don’t start thinking about full lifecycle costs of buildings. Something we’ve been looking at increasingly more is the idea that there are implications that go well beyond first costs. When we talk about buildings and some of this is starting to get picked up and actually instituted through legislation. And so, you know, whether you want to pay for the building performance upfront and you want to have better performing envelope, you could pay for that upfront, or you can pay for it on the backend. And so the new incentive structures, I think we’re going to start to see more and more, and we’ve seen legislation in New York City starting to penalize buildings for performing poorly over time. You’re going to start to see builders of buildings and developers start to look at and build in the cost of the performance of that building at the outset, instead of only looking at the first cost.
Right. I like that life cycle cost approach. And you said it pretty succinctly then either pay for your carbon now or you pay for it later. I feel like that could be a tagline somewhere in the future. What about mass timber? Jeff, what are your thoughts on added costs for mass timber structures?
So, it’s funny that David’s talking about the full lifecycle cost and taking that accountability. And I think from what I’ve seen on this end, it still seems a lot of developers in most markets, their lifecycle cost is when they build the building and when they sell the building and flip it to somebody else. And so, the definition of whose lifespan that is and who controls that is important to consider. And I think right now for a lot of developers, it’s still very much a first cost mentality and trying to tackle that varies depending on what the product is that you’re trying to do in the market, and the marketplace you’re trying to do it in, as well as whether the labor market conditions for your construction people as well. Depending on the type of application which you’re using with mass timber, it can still almost be the same cost as an equivalent concrete structure or possibly a premium depending on what you’re trying to do with it and where it goes.
I think that in large construction markets that could be very high carpenter scales, where you have to have a lot of workers it takes to build a concrete building and the foot carpenter is making $75 to $100 an hour. Those mass timber buildings are typically assembled with fewer people, where the material costs or the mass timber may be more than concrete, but the amount of labor that it takes to build that building could be offset significantly. So, in high labor cost markets, mass timber I think presents a very powerful argument against first costs, but in low labor cost markets, that may not be the case. And so, I think the New Yorks and San Franciscos and LAs and Chicagos where you have very high labor costs, I think mass timber can prepare a very compelling argument. But David, as you mentioned too, before about the lifecycle assessment, I think some developers don’t understand the cost makeup of what it takes to get their building up and develop that out of the ground.
They may know what they can lease that building for per square foot, and they may know a total overall cost of the building, but they don’t understand the makeup that goes into the buildup of that cost to build the building. You know, oftentimes if you’re having a mass timber structure, you want to expose as much of mass timber as possible so you can showcase the beauty of the wood. Well, if you’re going to do that, you know, you’re not going to be covering it up with drywall and doing a lot of drop ceilings and things like that. But then the concrete office building or steel office building, oftentimes you do put in drop ceilings, you don’t leave that structure exposed. And so normally a developer may not be cognizant of the additional finishes that go into a concrete and a steel building. And so sometimes when you’re like looking at the big picture, a developer needs to look at the total overall cost and the buildup to understand those nuances and if they don’t have to pay for the finishes, then maybe they can put a little bit more into the structure since the structure is more of a finish itself.
And just on that point, and again, you touched on the labor aspect of it as well, but there’s another component of that, isn’t there? That sometimes you see these subcontractor premiums on working with mass timber because of inexperience with it, but there could also be potential savings there. I think you mentioned in an example with the elevators that the master restructure is sort of more plumb and truer, you want to kind of talk us through that.
Yeah. So normally a mass timber superstructure that those CLT panels, if they’re built at eight feet by 64 feet, long, 10 feet by 60 feet, normally they’re built to a tolerance of two millimeters over 64 feet. And that’s a tolerance that you’re not going to get with a steel or with concrete. And so one of the things that we noticed that when we were building our hotels, when we were doing our shaft walls for our stairs and our elevator cores, our elevator subcontractor just blew through his production on putting the elevators in because all of his guide rails and everything else, his wall substrate was perfectly straight and true and plumb, he didn’t have to shim anything up and he could just blow and go. But one of the other things that we’ve discovered is, is that with any subcontractors, that they’re starting to work with mass timber, it is so new. There’s a fear factor where subcontractors don’t know what they’re getting into. As this gains more acceptance and traction, subcontractors will know what they’re getting into and then if they can start to price it with more stability and accuracy.
So, one other piece that I just kind of want to draw out is how you tend to leave the structure exposed. You want the beauty of the wood to really come out. How does this contribute to the overall health and wellness in terms of biophilia of a structure?
Yeah, well, there’s certainly a number of studies out there that have shown the positive impacts of access to natural materials and nature with health impacts. People tend to gravitate towards nature and natural elements. I have a reaction when I walk into a building that has a lot of timber elements, I think we can all relate to that feeling that it’s just there, there’s something warm about it. These are slightly harder to measure in isolation in terms of their individual health impacts, but we do know that they are there, and they do exist. You know, the other part of this is that there’s also a perception that people have when they’re in a timber building, that there’s a building that’s focused on environmental themes and features. And I think that the value of that we probably still need to see, and it’ll play out when leasing gets involved and decides that there’s value associated with this type of building. We’ve certainly seen a lot of interest from our clients and just the aesthetic of the timber frame building.
Yeah. The FP Innovations in Canada did a research study about, I think seven or eight years ago, where it talked about the human effects of being in wood, where they had taken the students and they had to do a test and they measured their EKG, and their skin temperature, the measure of stress responses as they were given these tasks, the rooms were identically furnished, except that the tabletops were either a white synthetic plastic or wood Birch. And the chairs were, you know, woodgrain, or they were just a white plastic, but they had the same shape and results of the students who are doing the tests, the reactions were more muted when they wear the wooden room, as opposed to a synthetic room. When you go into these new mass timber buildings that are exposed, I think it evokes a whole range of emotion. There is a calming nature to it and it’s just a neat vibe. I think that a lot of office spaces are starting to trend towards, you know, there’s a yearning to go back to those industrial loft spaces. Well, now you can get that old look with a newer material with more renewable resources.
Yeah. So Jeff, just to touch on a piece of that, when you walk into this building, right? So if you think about that from the perspective of locally harvested trees, you think about where you’re sourcing those materials from. So now you’re, you’re walking into a building, you’re getting that beauty and that feel, but you’re also getting a sense of place in a sense of culture, right. About where that building is in the moment in time and its geography. And I think that that can be pretty powerful on its own. So, I’m going to just ask you guys one final question before we wrap up here and I’ll let you each address it. David, from your perspective, these trends, net zero carbon and mass timber buildings, where are they going in the future? And is there anything in particular that we need to be doing to help them continue to grow in our industry
In terms of net zero buildings, I think it’s the future. And I think it’s the present. You know, obviously the science has been pretty clear. It’s been clear for a little while that we have to do something about carbon in a serious way. And we know the built environment plays a big part in that certainly in the structural elements that Jeff’s been talking about, finding alternatives or in some cases, lower concrete mixes, are going to be a big part of that. I think that inevitably, because there is so much focus on this and because, you know, with good reason, there’s some alarm around our building practice and how we respond to it, that there is also a heightened focus in terms of legislation that is coming, particularly as we see some of the changes, even with the new administration in the United States and some of the policies that have been put forward in Europe and around the world, you’re going to see different ways that governments are going to be looking to regulate carbon, whether it’s through the materials that we use or through the performance in the building.
We’re seeing now regulation around buildings and in the use of fossil fuels and moving to electrification, certainly legislation around materials and maximum limits on body carbon for particular materials. So, this is coming and will have to be a regular part of our vocabulary. And I think it’s going to be really important for all of us to get educated. So, I think this podcast plays a role in this, but all people who are invested in sustainable future and future generations play a part, and there are plenty of things to do, whether you’re specifying carpet or you’re building a mass timber structure, or you’re just teaching people about the definition of embodied carbon. I think it’s going to involve all hands-on deck.
Great. Thanks. How about you, Jeff?
There’s several trends that are sticking out to me. David’s hit on a number of those, but as our population continues to grow and our cities increase in its density, our buildings are going to have to start going up. And in the past mass timber was only allowed to go up five stories in height and with the recent passing of the International Building Code, the 2021 version, that’s going to allow the use of mass timber up to 18 stories in different tiered classifications. There’ll be a Type IV-A, Type IV-B, and a Type IV-C that allow you to go to different heights. Those different categories will also allow you to have certain amounts of timber that can be exposed versus timber, that some of it may need to be concealed versus all of it may need to be concealed.
So, from a regulatory perspective, we haven’t been able to typically build over five stories out of timber before, but now we can go with mass timber up to 18. And I think that as a lot of these buildings need to get taller in height to increase its land utilization. I think that mass timber can now play a role, especially in the six to 12 story range. And we can start doing a lot of those buildings out of the mass timber that you were typically either you didn’t see at all, or if you did see that they would be in steel and concrete. So the opportunity to do that now that you have the regulatory framework to allow for those taller buildings. Now when the cities and States start to adopt that framework, those jurisdictions adopt those codes during their regular cycles. And it could be every three years, it could be every six years.
And so, some of the States have already jumped on board, incorporating the 2021, the guidelines for the tall wood buildings, including, Washington and Oregon and California is going to adopt it in the next year as well. And I believe Utah has jumped on board. Other States are looking at adopting that, that framework. So even though they may not adopt the 2021 codes in whole, they are adopting just part of it to move forward to permit taller timber buildings. So I think you’re going to start to see a noticeable uptick in the development of those buildings in the urban spaces where you need to go taller than five stories. And you can start to do that with mass timber. So, I see a lot of trends moving this way for the desired aesthetics as well as the regulatory acceptance. I think a lot of good things are ahead for mass timber and carbon impacts.
Great. So I just want to thank you guys, both David brief, all of Gensler and Jeff Morrow of JMR solutions. This has been a wonderful conversation, and I’m so glad that you joined us today. Thank you.
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