No, thanks, Forbes. You can suck it.
eh?
got to the site fine and I have abp
How efficient or effective on the large scale would it be to use concrete for the exterior walls of residential homes compared to the current use of wood?
I think if I were in there and it were full of people I would just curl up and die. Building at inhuman scales doesn't work.
How efficient or effective on the large scale would it be to use concrete for the exterior walls of residential homes compared to the current use of wood?
Construction wise it wouldn't be bad. Your foundation and basements are already poured. You will use a good deal of wood in the forming process for the upper levels though. You also have to deal with expansion cracking due to heat and cold. The other issue is maintenance and utilities. You would have to pour hollow walls to allow pipes and wires to be ran. Expanding or moving outlets would be extremely problematic. Concrete is also porous and even when coated still allows water intrusion to an extent. Theres also all the moisture in the concrete from the initial mix which takes a great deal of time to evaporate out. The last two are a big reason not to insulate a concrete basement, you dont want to create a mold factory of trapped liquid. The other factor is insulation itself. Concrete is a poor insulator, so now we're back to adding insulation. Might as well just stick with wood.
I wouldn't consider that surprising consider US manufacturing peaked in the 1920s (45% of all jobs) and has been declining linearly since then (now 4% of all jobs).
America went through what China is going through now from the 1860s to the 1910s. 90% of the 20th century was America de-industralizing, whereas China is going the other direction.
Why not just put a smaller inner wood wall on the inside to allow for that, while still keeping the strength and durability of concrete in dealing with weather and natural disasters?
Why not just put a smaller inner wood wall on the inside to allow for that, while still keeping the strength and durability of concrete in dealing with weather and natural disasters?
It probably has to do with labor and cost more than anything.
A guy who knows how to use a nail gun, hammer, and power drill probably costs less than a guy who knows how to tie-off miles of rebar at the proper measurements. Then you have the form-work, setting time for concrete to get some strength, and weight of concrete itself -- gotta transport heavier stuff and build higher-quality walls/floors/beams to hold it all up.
Rebars not extremely expensive, but it aint cheap either. You'd need a pumper truck to pour the walls so you didn't get cold joints. Not to mention concrete isn't cheap either.
Per pound rebar is more expensive. The concrete is a bit more than that. It's cement (which contains the lime), 3/4 chip (generally), sand, water, and then various admixtures to adjust air, water, etc in the mix. The amount of mud you need vs the bar is what gets you. That and mixing companies charge insane rates. Expect to be around $150/yd.Funny actually. I would think the rebar would be notably more expensive than the concrete. One has to be found, mined, smelted, and then formed, while the other is just lime, cement, and crushed rock.
Per pound rebar is more expensive. The concrete is a bit more than that. It's cement (which contains the lime), 3/4 chip (generally), sand, water, and then various admixtures to adjust air, water, etc in the mix. The amount of mud you need vs the bar is what gets you. That and mixing companies charge insane rates. Expect to be around $150/yd.
That part where they have to cook the ingredients for cement at 900 C or something probably adds to the cost a bit.
Eliminates the need for the wood forming and solves the porosity issue.
Cement itself (Portland Type II in my experience) is not extremely expensive surprisingly. It probably has to do with the volume at which we get it, but #4 bar is 6 times more expensive per pound than cement (excluding delivery for both). The finished concrete though adds up. Again it goes back to volume. 1 yard of concrete is 4000lbs at roughly $.03 per pound. A yard is 3' cubed. Doesnt go very far when constructing a large structure.
I am assuming that the rock and sand is notably cheaper than the cement mixture. So the major costs of concrete are from the labor and contracting?
Do you have a link? I do Precast work as opposed to on site contracting work so I'm not on the up and up with buildings, just the mud and utilities.What do you think about the Russian concepts? Kinda limited to high density structures, but it is still relevant to general construction science.
I am assuming that the rock and sand is notably cheaper than the cement mixture. So the major costs of concrete are from the labor and contracting?
One was just opened, the other was about to close. You want me to go get pictures of malls in the US that are also abandoned?
The media is portraying the exceptions as the norm. Ordos is the most extreme exception and that city still has a lot of people living there.
Do you have a link? I do Precast work as opposed to on site contracting work so I'm not on the up and up with buildings, just the mud and utilities.