Lloyd Alter surprises me with this statement on Treehugger.com as he discusses the world’s largest building constructed with Cross-Laminated Lumber:
Anthony Thistleton, speaking in Toronto at the Wood Solutions Fair, explained that the reasons for using CLT are prosaic: it is a lot lighter, a fifth the weight of a concrete frame, so it doesn’t need deep pile foundations, which would have been problematic with a new Crossrail subway line going underneath. It goes up a lot faster, and in real estate development, time is money. Because the CLT has a bit of insulation value, it needs less additional insulation. Because the CLT buildings have more wall and less column, there is less infill framing. So that overall, the cost often ends up being less than building with concrete.
All those other green benefits, the storing of carbon, the saving of 600 heavy trucks running through London, the renewable resource? Nice to have too, but the real story here is that you can build a better building for cheap.
Thistleton said he wasn’t thrilled about cladding the building in brick, necessary to fit in with the neighbourhood; he thinks it’s inappropriate to put such a heavy cladding on such a light building. I don’t agree; architects have been putting brick facades on wood frame buildings for centuries, and it does fit in with the neighbourhood. I love how they photograph the building from in front of an old brick wall with old mattresses and junk; it is now part of the urban fabric. “The building’s intricate brickwork references both the surrounding Victorian and Edwardian housing and the craftsmanship-like detailing of the local warehouses.”
The brick also gives it a bit of weight; Thistleton notes that a problem with such a light building isn’t holding it up, but holding it down. Wind loads become more important.
It hadn’t occurred to me that generally reasonable winds might cause a building made of lumber to take flight. Naturally, extreme weather such as tornadoes and hurricanes are a different matter, but the implication here is of more reasonable winds.
