The annual WoodWORKS! International Wood Symposium this year is all about tall towers. Towers constructed from timbers, that is.
Among the themes: Who is building them, what are the latest materials and techniques and how are developers getting them built in a sector still geared toward concrete and steel?
Designers of the world’s tallest timber tower (for now), the 14-storey, 52.5-metre-tall Treet building in Bergen, Norway, attended this year’s edition, sharing their experience and passing the torch to the most prominent project in British Columbia, the 18-storey, 53-metre Brock Commons student residence at the University of B.C.
The Sun caught up with both groups — architects Russell Acton and Christoph Dunser with Brock Commons and project director Ole Herbrand Kleppe and engineer Rune Abrahemsen with Treet — during the symposium at the Vancouver Convention Centre to talk about how they are advancing the cause of tall wood buildings.
The following is an edited and condensed excerpt from those conversations.
Q: Mass-timber construction is still relatively new in North America. What made you want to be part of the Brock Commons project?
A: (Russell Acton, Acton Ostry Architects) What we found interesting about the project was that UBC was approaching it in a very practical, straightforward way. It wasn’t (like) so many wood projects around the world, a showcase project. UBC was very interested in, ‘Can we construct a mass-wood building similar in cost to concrete or steel?’ That was the challenge, and the answer was yes.
A: (Christoph Dunser, Hermann Kaufmann ZT GmbH) It’s not a (flashy) building, the most important thing in the world. But it has an impact, on the (construction) market, on the economy, ecologically.
Q: How important a project do you think it is?
A: (Dunser) I think it’s very important, because if you can deliver a good solution, it’s going to be promotive for future development. You have to make some compromises to fit the market, but in the end (conditions) will improve because minds will change a little bit.
A: (Acton) All we need after that is to get mass wood into the building code. It won’t be the next (edition) but the one after that, and then this project will have demonstrated to builders that (building with mass-timber methods) is very straightforward (and) economical, particularly when we get more supply (of materials) in the industry. And over time we need to build up the industry for prefabrication. That’s again going to lower prices.
Q: With the Brock Commons project, what has been your biggest obstacle?
A: (Acton) I don’t really consider there to have been obstacles. I would say the biggest challenge was getting approval to build the project. It’s permitted, in a roundabout way. You have to go through a process to demonstrate that it’s as safe as if it were built from concrete or steel. To the government’s credit, they really worked collaboratively and proactively to make that approval happen.
Q: As we look forward, what are the limits going to be for building with mass timber?
A: (Acton) I think the sweet spot is going to be, (as Robert Malczyk) said in his presentation, probably four storeys to eight, 10 storeys. There is a huge amount of demand for that kind of project and the structural systems would be perfect for that. Then some might choose to go higher.Q: What would you say are the limits for building tall?
A: (Rune Abrahemsen, Moelven Limtre AS) If you build a pyramid with stone, you can imagine you could build a pyramid using wood. If the base is big enough, you can build it sky high, but that’s not practical. Using our building system you could easily go up to 20 (storeys) maybe pushing 25. Changing the system a little bit, you could go higher — 30 storeys would not be a major challenge.
A: (Ole Herbrand Kleppe, Bob Eiendomsutvikling) In Europe, particularly Nordic countries, there is not a demand for this kind of building, 30 storeys are rare. Up to 20, 22, 25 storeys, yeah, maybe.
A: (Abrahemsen) But for Vancouver, 30 storeys is common, so that would fit here.
Q: Why did you want to be involved in the Treet project?
A: (Kleppe) Bob is a corporate housing association that has as a goal to be a leader in urban development. We have a strong focus on sustainability, energy efficiency. In that perspective, this project turns out to be partly an answer for that. More and more people are moving to the cities (and) we need to build more and more apartments in the cities, but without consuming more land. So we have to make more highrise buildings, and Treet is a lighthouse project to show you can actually do that and still make them with sustainable materials, like wood.
Q: What was the biggest lesson you learned that you would want to pass on to the developers of Brock Commons?
A: (Kleppe) Focus on prefabricating elements with a high degree of accuracy to do a project like this. In Europe, we have an industry already producing these elements. On this particular project, we had a whole (one-bedroom) apartment delivered as one box. Modules.
A: (Abrahemsen) In the next project, we will strive to use even more prefabricated elements because we see the benefit from that. We save construction time, we get higher quality, we get less problems from moisture during construction. There are so many benefits doing it that way.