https://en.wikipedia.org/wiki/Glued_laminated_timber
Consider this picture:
https://en.wikipedia.org/wiki/Glued_laminated_timber#/media/...
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The "Glulam versus steel" section is really interesting!
> A 2002 case study comparing energy use, greenhouse gas emissions, and costs for roof beams found it takes two to three times more energy and six to twelve times more fossil fuels to manufacture steel beams than it does to manufacture glulam beams. It compared two options for a roof structure of a new airport in Oslo, Norway: steel beams, and glulam spruce wood beams. The life cycle greenhouse gas emission is lower for the glulam beams. If they are burned at the end of their service life, more energy can be recovered than was used to manufacture them. If they are landfilled, the glulam beams are a worse alternative than steel because of the methane emission.[9] A more recent study by Chalmers University of Technology was not so optimistic. Nevertheless, it showed that while the absolute greenhouse emissions are strongly dependent on the method used to calculate them, the environmental profile of glulam is typically as good as or better than steel in an example structural application.[10] The cost of the glulam beams is slightly lower than the steel beams.
It seems like people are using them, so I presume it's safe. I don't think I would want to live in them until we've seen a bunch of them catch on fire. I'd probably be fine with it up to 3 stores, but anything higher would make me concerned.
We should use more wood.