Ep 135 - Tall wood buildings with Meike Engel & Ornagh Higgins

Adam Jones (00:26):

All right, well we'll get into it. So, thanks so much for coming on the podcast, Meike and Ornagh, can you start by telling us a little bit about yourselves, what you do, a bit about aspect engineering, your design company?

Meike Engel (00:39):

Yeah, absolutely. So, my name is Meike. I'm here with Ornagh and yeah, the two of us work for Aspect Structural Engineers. We're a design firm based out of, I mean our headquarters is in Vancouver and we were founded in 2016 by five partners. And since then, we've grown into a handful of offices now. So, we've got our headquarters in Vancouver, we're also located in Toronto. We have another office in Switzerland, and then our fourth office, which we just announced is in Seattle. So, we're really excited about that. But yeah, we're a design firm made up of about 60 engineers now and we work in all main material types, but we're really passionate about mass timber design, but also do steel and concrete design. And then my background is I actually started as an intern at Aspect back in 2018, so I did an internship here after that. I did an internship at Structural Land, which was a major mass timber fabricator based out of British Columbia here. And then after my graduation I joined Aspect full time and I've been here ever since. Yeah,

Ornagh Higgins (02:01):

Okay. My name is Ornagh, I am Irish, so from Ireland and that's where I studied. I went to Trinity College there. I did do one semester in Milan and then did an internship with Hilti in Liechtenstein before returning to Dublin to finish my studies. And then when I graduated, I moved to London and worked predominantly in retail and leisure projects, mostly steel construction. And then four years ago moved to Vancouver and joined the Aspect team and really got into mass timber design from then.

Adam Jones (02:39):

Great. And Aspect's, definitely got a tier one brand globally and I know you've been a part of as a company, some majoring projects. So, can you start by telling us a little bit about what projects the team's been part of and also the ones that you've been contributing to? And that'll get us back into the rest of the topic where we'll talk about tall buildings

Meike Engel (03:01):

For sure

Ornagh Higgins (03:02):

Sure. Yeah, sure. So, one of our more notable projects is Tallwood 1, which is on Vancouver Island in Langford. It's in a really high seismic region. It was the first tall wood construction to the new encapsulated Mass timber code, which came out, it's a 12-storey point supported CLT on glulam columns with EVF brace frames and that finished construction in 2022. We've also got a number of other projects in design, a couple in Seattle, one 17 story, which is 12 stories of mass timber on five stories of concrete, and that's sort of in the early construction document stage. And then just a couple more residential in tall timber and a lot of hybrid systems we're seeing, especially for the multifamily up to five, six stories, CLT floors on light wood frame walls is a really good construction type. So, we have quite a few of those projects as well.

Meike Engel (04:08):

And then we've got some kind of unique projects as well, including the Malahat Skywalk project, which is also on Vancouver Island. It's kind of a cool tourist attraction, a nice skywalk that you can go visit. And then we have a lot of custom home projects, and we also do temporary works engineering for quite a few mass timber buildings.

Adam Jones (04:32):

Yeah, that's great. And you mentioned that there's a lot of projects that you've been part of essentially. So, what are some of the systems, say as you go from the smaller buildings up and as we scale higher, how are we actually doing a different mix of materials and different mix of solutions from the small scale, medium scale and then higher scale?

Ornagh Higgins (04:55):

Yeah, I think we're seeing, we have quite a lot of projects in when we talk low to mid, so up to five, six stories, light wood frame walls with CLT floors is a really good system and a really good entry point for people looking to get into mass timber who were maybe in the light wood frame world before. And it works particularly well for residential because you have those light wood frame walls anyway. If we're talking about office buildings, we're typically seeing we've got beam and post construction as the most common, just looking for those longer spans open spaces. And then as we go taller, definitely the beam and post-construction and the point supported CLT are the two sort of most common construction types we're seeing. So that's sort of like, yeah, definitely as we go 12-storeys and up from there.

Adam Jones (05:46):

This might be a really basic question, but in Australia and New Zealand, the light frame market doesn't really have that 3, 4, 5 story buildings. It's all concrete. So, I'm interested to know what's the market share of just at the higher level of the light frame compared to concrete? How often does the light frame one come up with CLT floors?

Ornagh Higgins (06:10):

I think the light wood frame is definitely really common light wood frame with CLT floors maybe less, but I think that would be just lightweight frame in the market is probably just generally stronger, I'm guessing, that is what you're seeing in Australia. I think a lot of the benefits we're seeing with the lightweight frame is just really fast direction time. Especially now we're seeing a lot of prefabricated walls coming in and there's a few companies coming out now who are doing really great work in that prefabrication of these light wood frame walls and we're seeing a really quick construction time on site. But even I think probably the light wood frame market in general is stronger here. I'm guessing we still have concrete and steel of course would probably be more common. But yeah, I think it would definitely be the majority of the market share.

Adam Jones (06:58):

Yeah, so no doubt, some of the first projects that you've been part of, you go through things, there's scars and there's things you wish you learned along the way. And so what are those things as an organization that you realize, look, these are the things that just have to be agenda items at the start, these are the things, the most important things that we've learned on these mass timber projects on our journey so far.

Meike Engel (07:27):

I mean I think we've definitely learned that it's really important to have, I mean ideally if you can have your supplier on board early, that helps a lot in developing your schematic design to develop an efficient schematic design. And it's also just really helpful to understand their capabilities in their shop and also the installers input is really valuable to have throughout the design process so that you can hone down on what kind of connections they want to see and what their sequencing is like. Yeah,

Ornagh Higgins (08:09):

And I guess to further what Meike said about suppliers and design for Tallwood 1, we actually had a supplier chosen the schematic design. So really early on, partially because there was limited suppliers available in the area at that time it is much more now. So knowing exactly what their manufacturing capabilities are and what panels they have available meant that we could come up with a grid layout that really maximizes the CLT in terms of efficiency and especially with point supported CLT where you see you have quite a close column grid center, being able to maximize that as much as possible really helps with the layout. And then for a lot of our projects now, what we're trying to do is have an early tender if possible, so bringing that tender day forward maybe at the end of the design development phase because up to that point we could have a design for multiple suppliers.

(09:05):

Typically, we would look at North American suppliers, European suppliers and have different options on our drawings. For those suppliers, it's not really practical to bring that through later on in the project as we go get more detailed design. So yeah, end of DD phase, we'd have enough information on our drawings so that we could do an early tender just for the mass timber portion and then when we go to the next stage of the design, we know who our supplier is, we can get them on board and just really hone in the design specific to what their products are and what their capabilities are.

Adam Jones (09:37):

Yeah, that's excellent. That is something that keeps coming up on the podcast. It's like “choose a supplier early” but you want to keep competitive tension. So, it seems like you have a really early process to actually choose a supplier to make sure they're on board and part of the team at the very start. Hey.

Ornagh Higgins (09:56):

Yeah, and I think just for an example, there's a carry house project in Seattle, the 17th story which is 12 storeys mass timber on five of concrete there we also have the builder on board VM builders and having them on board really early means that when we go for this early tender, they can review all the tenders, they're really experienced in mass timber, they can see any scope gaps allow for that and really able to draw a good comparison between because it is an early tender still we don't have a full detailed design. So having someone on board who really knows the product and the market and what might be missing from different tenders so that we can compare them fairly I think is also really helpful.

Adam Jones (10:37):

Great. And how is the supply chain maturing at the moment? Do you see, are all the factories too full and the lead times ridiculous or is it a stage now where it's the right balance between a supply chain, a mature enough supply chain to actually deliver on what architects might be pushing at the start?

Ornagh Higgins (10:58):

Yeah, it's a good question. I think it's been varying a lot. I think what's interesting with the supply chain is how different markets affect the pricing that's coming back. So, for example, coming from Europe now, I think they may be a bit slower and maybe not at full capacity. So, we're seeing pricing is really competitive coming back from there, I don't think we've seen any sort of major delays or people saying we have too much that there's the market saturated, they're saturated and they can't produce. But certainly, you're booking a slot of time that's quite far out, so you are booking that months in advance for your project. And generally, I think it seems to be okay and we seem to be able to get those and I guess the pricing would also be reflective of how much they're seeing coming in and how much they're going in. So

Adam Jones (11:53):

Great. So, looking at taller buildings, everyone gets super excited by going taller. What are some of the design challenges as we get higher and how can we start combining with concrete and steel in smart ways to actually enable more mass timber in higher buildings?

Ornagh Higgins (12:15):

So, I think in terms of combinations with steel and concrete, definitely for lateral systems, having steel or concrete lateral systems now for tall timber buildings is pretty much what we're seeing. And the way forward generally trying to do lateral systems for taller mass timber buildings is difficult. I think we will see more of it in the future, maybe up to 10 storeys. I know there's a lot of testing for CLT Shear Wall up to 10 storeys, so I think we'll see some introduction in the code for that sort of thing. But for the moment, the CLT Shear Wall for lateral systems, it's quite restrictive in what you can do and how you design it. So not very common in taller buildings or really possible. And then in terms of just the gravity system and combining those, I think for point supported CLT, sometimes we see steel columns used synthetic glulam columns, which can be a nice alternative just in terms of the capacity and the size of the columns that you're seeing and just being able to fit those columns maybe within a demising wall as opposed to having a glulam column which might be slightly larger than what your demising wall is.

(13:31):

And then again, we are seeing some like the delta beam for example, again, another hybrid system to allow for long spans if you want to open up the space a bit more than what maybe your traditional beam post might offer or if you're trying to avoid those down stem beams in your beam and post solution

Adam Jones (13:52):

Question.

Ornagh Higgins (13:53):

I might've gone off quite there a little bit.

Adam Jones (13:55):

That's it. Yeah, one of the most important things too, and projects that seems to be come up a bit is obviously cost. Everyone cares about cost and that's always linked to speed of construction as well. To actually claw it back, and you might've already touched on this, but how can design program be optimized as much as possible for everything to just get that cost? I guess if it's the triple bottom line sustainability, tick, human health and biophilia tick, you can get that third one on cost as reasonable as possible then if things start to become a no brainer.

Ornagh Higgins (14:36):

And I think cost is obviously a big thing. I think one thing is just seeing if we can let the structure sort of lead the design and how much the architect is willing to do that. So, can we come up with a grid layout that really suits mass timber and is designed to suit mass timber? Can it be a very regular grid layout? Can we sort of come up with some key details that then get repeated throughout the project just to make it a really efficient and economic design That's really important. I think again, having that from the offset rather than having a building which maybe it was designed for sailor concrete first and trying to switch to mass timber, but that grid just doesn't really suit what the mass timber wants to do. I know in tall wood one we had a very regular grid and the architect, it was like a three by 3.6 and we repeated that grid across the whole floor plate and the architect was able to work with those columns and just made it work with their internal layout.

(15:39):

So that allowed that structure to be really efficient. And I think in the end when they did a cost comparison on that project for the mass timber versus the concrete, it actually came out pretty much equivalent and we didn't really see a price premium for using mass timber there. But I think the speed of erection is another really good point because that's something that we often hear when we're talking about cost savings going with the mass timber scheme. And it's interesting because I think when we look at a concrete, it's obviously a longer time for a concrete building to be constructed. And what we found at Tallwood, it was actually trying to get the rest of the trades to keep up with the speed of construction of the mass timber. And particularly we had one issue, it was during Covid there was some procurement issues with the exterior walls which were meant to come in. So, we actually had to stop construction waiting for those walls to come in, which slowed down the construction there, which was unfortunate. I think it could have been a much faster timeline than what we actually saw. But yeah, I think it's important that the builder knows that from the offset and they're able to keep up with the speed of construction of the mass timber.

Meike Engel (16:54):

Yeah, I think a key point is to design a mass timber building assuming that you will be designing a mass timber building from the very get go. So, if you can optimise your grid sizes based on using mass timber right from the beginning, you'll be able to design a much more efficient building. I mean anything is possible for mass timber. We see things like timber concrete composite, but which can be a great system for achieving really long spans and things like that. But in terms of speed of erection, a lot of the time that can be a hindrance. You need to wait for the concrete to be poured at certain stages of the project to kind of gain stability and strength throughout construction. And so, the mass timber installation team oftentimes doesn't want to wait for that additional trade to come on site. So, if you can avoid that, it really pays dividends on your speed of erection and your costing.

Adam Jones (17:53):

Yeah, that's great. And Meike, what do you see is the future of timber construction? And maybe we can have a few threads there and maybe we'll start on a technology. Have you got thoughts on technology? You probably saw chat GPT4 last week and there's all these things coming out in AI. You've got robotics, you've got parametric design, grasshopper, all these sorts of things. So, on the technology front, do you have any thoughts on how this might be used by designers and change our processes?

Meike Engel (18:29):

It's a loaded question, but I mean I

Adam Jones (18:31):

Think it's for sure.

Meike Engel (18:34):

Yeah, for sure. We've had conversations about this in the past and we've had some people in recently into our office speaking about some of these tools that they're developing. So, I mean it'll be great to see more softwares come out to quickly design to do the schematic design stage of a building like sizing members and things like that. It's not rocket science. So if we can get more tools that will enable us to do that kind of work quicker, we can kind of focus on the challenging bits of designing the structure And also just in terms of codes and things like there's a lot of different codes that we're referring to currently. Obviously, most knowledge in mass timber construction is currently coming out of central Europe, so if things aren't codified yet in North America, we kind of have to lean onto these codes. So, I think the future of mass timber will kind of depend on unifying the approaches. Yeah,

Ornagh Higgins (19:46):

I think the same, even internally we're looking at ways how do we stop repetitive design and come up with clever ways to leverage on this technology that's becoming available to do the design and also produce our drawings so it's not as manual. I think in terms of code, kind of pulling off what Meike has said, I mean mass timber is still a relatively new material in the construction world when compared to steel and concrete. So, I think we're going to see a lot more of the kind pre-engineered connectors, which were already really popular, but more of that as opposed to the custom seal hangers. I think we'll see, I touched on this briefly earlier, but the CLT Shear Wall design is currently very prescriptive and quite limiting in what you can do. So, I think we'll see a lot in that advance over the next few years and probably become more popular in use.

(20:42):

One thing we don't cover very well currently in north is design of robustness in mass timber buildings. It's covered very well in the Euro code with various different methods like notional element removal or tying forces, vertical and hard, providing vertical and horizontal ties. So, I think it would be great to see that introduced into the code here in some way and probably something we'll see in the future. And also, things like point supported CLT currently isn't codified, and again, I know there's a lot of testing going on around that, so I think that's another thing we'll see come in.

Adam Jones (21:22):

Yeah, it's definitely an exciting future. It's been incredible to speak to both of you, Meike, and or if people want to find out more about both of you and get in touch about any projects they might have in the pipeline, how should they reach out?

Meike Engel (21:40):

Definitely reach out to us on, I mean we're both on LinkedIn, you can reach out to us there or just email our office and it'll get passed on.

Adam Jones (21:51):

Fantastic. Well thanks so much for coming on the podcast. That was absolutely excellent, and you guys killed it.

Meike Engel (21:59):

Awesome. Thank you.