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Comment by buss | Hacker News Reader

It's all engineered lumber. "This high-rise is being built using glulam, CLT, and Metsä Wood’s Kerto® LVL (laminated veneer lumber)"

glulam = glued laminated timber AKA pieces of regular timber stacked & glued together CLT = cross-laminated timber AKA glulam but instead of stacking the lumber, you lay it out in perpendicular layers and glue it together LVL = laminated veneer lumber is like the above, but made like plywood out of wood bits instead of solid lumber, with a hardwood veneer on the outside

The wood is also treated to be fire, moisture, and insect resistant

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Given one of the things that wooden buildings inspire is a "Hey, we CAN build big buildings in a green manner", how do all the things you mention impact that?

It sounds like gluing, treating etc. etc. would really impact the "greenness" of this building

I think the green-ness relates more to the fact that growing timber captures carbon dioxide, while producing steel and concrete emit carbon dioxide. The production of the glue, and the processes to glue the timber together certainly emit CO2, but nothing near the emissions of a steel foundry.

Cement production emits 5% all man made CO2 emissions.

That's true, but here's a thought: Using engineered wood products potentially allows undesirable or unconventional wood sources to become useful building materials, rather than having to source old growth timber for larger beams/columns. There could be some environmental benefits associated with that.

I agree with your comment but I just need to point out that beam/column timber is not old growth wood, it's usually just from normal commercial plantations.

You're right for typical studs, joints, posts, etc.

However, I was thinking that for a highrise timber building, you might need way larger column cross sections than what we're used to seeing (24"x24" - 36"x36" or larger). The typical wood frame construction method of using a ton of load bearing sheathed stud walls scattered throughout doesn't work with these taller types of buildings. You start to see post and beam/panel type framing, which means higher compressive loads, which means larger member sizes.The spruce/pine/fir trees slated for harvesting softwood lumber here in Canada don't seem to reach that size. Hence, you probably need engineered wood products. As a bonus, you also get better and more consistent mechanical properties.

Old growth wood is not suitable

On top of the other replies, you should keep in mind that being more green than producing concrete is pretty easy.

It does, but the material is still carbon-negative, the article says.

In any case, anything is better than concrete.

What’s the problem with concrete? Edit-answered above, concrete produces carbon while wood stores it.

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