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The us doesn't use concrete for residential walls (very often) but that is actually quite good from an insulation perspective. Hollow wood framed walls have a l

The us doesn't use concrete for residential walls (very often) but that is actually quite good from an insulation perspective. Hollow wood framed walls have a lot better r factor than solid concrete. We do have solid concrete foundations. Edit: hollow walls filled with fiberglass to keep the air still

taneq 7y ago
With hollow walls you can just use blow-in wool or cellulose insulation to make it even better. Can't really improve concrete without gluing polystyrene to it. Hmm, could you just mix expanded polystyrene balls in to cement to make a high-R composite that's still strong enough to be structural?
- the8472 7y ago
  Foam glass bricks are available as insulation layers as alternative to polystyrene. There was a german company that produced foam glass concrete but they shuttered production.
- shereadsthenews 7y ago
  Usually concrete walls have a foam core. Solid concrete is only about R0.5/in, about half as good as wood. Even so, insulated cavities are totally obsolete. Exterior foam is far superior.
  - taneq 7y ago
    Wow, really? Interesting, the one's I'm familiar with (used in tilt-up construction) are just solid concrete (maybe plus some rebar). Totally with you on exterior foam though, you want the insulation outside of the thermal mass if at all possible.
    - dillonmckay 7y ago
      Check out ICF: https://en.m.wikipedia.org/wiki/Insulating_concrete_form https://en.m.wikipedia.org/wiki/Insulating_concrete_form There may be some copyright shenanigans w/ that page. There have also been successfully constructed in-ground pools using this material, but appears to be controversial to traditional pool-builders.
  - galangalalgol 7y ago
    What are the common ways to protect the exterior foam?
    - shereadsthenews 7y ago
      You put the building cladding, whatever it is, outside the foam. So usually from inside out: a wall, foam on wall, drainage screen, cladding. Can be brick, wood, whatever. There’s also exterior foam cladding that’s made to be open to the elements but it doesn’t look great or last a long time either.
officialchicken 7y ago
> The us doesn't use concrete for residential walls (very often) but that is actually quite good from an insulation perspective That is an incredibly incorrect set of statements. The insulation value of concrete, it's R=0.52 per inch of thickness. A vast amount of housing in many regions across the world is concrete (including the walls). Obviously, it is more common in multifamily construction and/or hurricane prone areas. Hollow wood framed walls w/o insulation depends on the relative humidity, but it's R<2. Fiberglass batt (R-12 and higher) is basically the only source of insulation in a wood sheathed wall.
- cheerlessbog 7y ago
  GP meant that its good that concrete is less used, because it has poor insulation properties. You seem to agree.

taneq 7y ago

With hollow walls you can just use blow-in wool or cellulose insulation to make it even better. Can't really improve concrete without gluing polystyrene to it. Hmm, could you just mix expanded polystyrene balls in to cement to make a high-R composite that's still strong enough to be structural?

the8472 7y ago
Foam glass bricks are available as insulation layers as alternative to polystyrene. There was a german company that produced foam glass concrete but they shuttered production.
shereadsthenews 7y ago
Usually concrete walls have a foam core. Solid concrete is only about R0.5/in, about half as good as wood. Even so, insulated cavities are totally obsolete. Exterior foam is far superior.
- taneq 7y ago
  Wow, really? Interesting, the one's I'm familiar with (used in tilt-up construction) are just solid concrete (maybe plus some rebar). Totally with you on exterior foam though, you want the insulation outside of the thermal mass if at all possible.
  - dillonmckay 7y ago
    Check out ICF: https://en.m.wikipedia.org/wiki/Insulating_concrete_form https://en.m.wikipedia.org/wiki/Insulating_concrete_form There may be some copyright shenanigans w/ that page. There have also been successfully constructed in-ground pools using this material, but appears to be controversial to traditional pool-builders.
- galangalalgol 7y ago
  What are the common ways to protect the exterior foam?
  - shereadsthenews 7y ago
    You put the building cladding, whatever it is, outside the foam. So usually from inside out: a wall, foam on wall, drainage screen, cladding. Can be brick, wood, whatever. There’s also exterior foam cladding that’s made to be open to the elements but it doesn’t look great or last a long time either.

officialchicken 7y ago

> The us doesn't use concrete for residential walls (very often) but that is actually quite good from an insulation perspective That is an incredibly incorrect set of statements. The insulation value of concrete, it's R=0.52 per inch of thickness. A vast amount of housing in many regions across the world is concrete (including the walls). Obviously, it is more common in multifamily construction and/or hurricane prone areas. Hollow wood framed walls w/o insulation depends on the relative humidity, but it's R<2. Fiberglass batt (R-12 and higher) is basically the only source of insulation in a wood sheathed wall.

cheerlessbog 7y ago
GP meant that its good that concrete is less used, because it has poor insulation properties. You seem to agree.