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by mywittyname 1851 days ago
Costs.

The type of lumber used to frame American houses is (well, used to be) quite cheap. Concrete is like $10 per cubic foot. While, a timber framed wall is mostly air. An 18x8 foot wall made of timber would take about 16 boards to make and take an experienced team less than 20 minutes to put up. That's $100 or so in material costs at current (extremely high) prices, plus maybe $100 in labor (this is pretty hard to estimate, actually).

That same wall would be like $700 if made from concrete. And labor costs would be probably equally as expensive because those forms take a long time to assemble. They need to be shipped in, assembled, left to cure, disassembled, then hauled away. While lumber just needs to be dropped off the back of a truck into a pile in the yard.

3 comments

Poured concrete will often use a lot of lumber anyway, since the concrete needs forms to be poured into. However, using precast concrete or CMUs avoids this.
Another type of concrete construction in parts of Asia uses prefabricated, reinforced concrete members. Piers, beams, and panels with internal steel made in a controlled factory setting and having high strength. It's a bit like half-timber construction but replacing the thick timber with concrete. They also use similar concrete for telephone or neighborhood power poles.

They are brought on site and erected by cranes and pile drivers to build the frame of a house somewhat like with large timber. The panels are set across beams to fill in floor areas, and walls are closed with non-load bearing elements, whether brick, blocks, stucco, drywall, etc. I am not sure how well this method works for seismically active areas though, where you would need to tie those in-fill wall areas into the structure.

Also, a lot of home construction in the US is single family and this type of construction is by and large mostly wood.

Concrete is used as a base for apartment (like four or five over two) but wood still makes up the majority, and there aren’t a whole lot of residential projects in the country built as massive concrete tower blocks outside of some specific regions.