So they're banning structures made of 100% biodegradable material that offsets carbon as it grows and is planted exclusively for this purpose, in favor of concrete and steel? Interesting.
The other thing is earthquake safety. Wood frame is often far more resilient to sheer stress than concrete/brick. Concrete can be reinforced to mitigate that, but I wonder how viable that is for buildings on the scale of SFH, not major developments.
Can confirm lived on tbe Big Island of Hawaii for three years. Almost all homes are made of wood with the houses literally standing on top of the volcanic rock or cement pilings. With frequent earthquakes (largest when I lived there was 6.8) the houses literally move, shake and flex.
It’s not just about reinforcement (like rebar or steel frames) but the concrete mix used. Even though it might not look it, most concrete used in buildings is flexible. The most earthquake proof building in SF is probably the Salesforce tower, which has a concrete core, not a low height timber framed house. Concrete has other great properties as well - it is waterproof, doesn’t rot, and is fireproof. On the emissions side, you can get flexibility and lower emissions by using newer air-crete mixes:
https://www.infrastructurist.com/what-is-flexible-concrete/
"The movement" isn't exactly driven by Big Concrete to begin with though. It shouldn't be a surprise to anyone that there are a lot of people and businesses in the world that don't give a damn about climate change. If there weren't, we wouldn't be in this mess. "The movement" is trying to counter them.
They don't seem to be weighing any factors at all, other than fire safety. Wood is renewable, cheap, cheaper to construct with, much more environmentally benign than concrete, very fire-safe (though not as safe as some), etc., etc.
As was mentioned by other commenters, affordable housing has a value that can be balanced against fire safety. Carbon contribution as well.
Everything has trade-offs. "Safe Enough" needs to be an allowable state.
I still remember when the primary environmentalist movement was "save the trees"; doesn't more wood use imply more deforestation? The wood that's in buildings won't be capturing CO2, it's the live trees that do.
No, because all or nearly all building lumber in the US and Canada is sourced from sustainably-managed timber lots. In other words, trees are re-planted, and clear-cutting is no longer a common practice.
Wood results from captured carbon. Live trees are captured carbon, as is lumber. Dead trees decompose and release the stored carbon back into the atmosphere. Wood used for lumber, unless it’s some exotic wood from the Amazon, is usually sustainably harvested.