Normally, people use Autoclaved Aerated Concrete (AAC) to build a concrete house because ACC is a good thermal insulation brick that easy to buy and not expensive

And another way i've heard about insulation wall is Cavity wall. IMO, it rarely find a house that use this kind of wall.

Then the main topic of discussion here might be

Autoclaved Aerated Concrete (AAC) wall vs Cavity wall which one is the best thermal insulation wall?

Note that another method can be purpose if it better than ACC wall and Cavity wall

  • 3
    $\begingroup$ For what climate? Are you trying to keep heat in or out? Is the intention to have high thermal mass, or low? What's your ventilation strategy? Are insurers fussy about particular construction methods? Is this coastal or any other location exposed to driving horizontal rain? Does the wall have to be structural? $\endgroup$
    – 410 gone
    Feb 10, 2015 at 13:44
  • 1
    $\begingroup$ Are you filthy rich? If so, use aerogel. Though calling it "best insulation" may be wrong, because it's by far too efficient - your body heat alone would make your room unlivable. :) $\endgroup$
    – SF.
    Feb 10, 2015 at 14:53

2 Answers 2


An AAC wall has an insulation R rating of 1.43. A cavity brick wall has an R value of under 0.82. So AAC isn't even double the insulation of cavity bricks, and at this point AAC may not be as inexpensive as cavity bricks + standard insulation.

There are many, many construction walls that have much greater R values, but as you've not given any information on your structure and environment it's impossible for us to weigh tradeoffs for you.

Keep in mind, though, that a standard 2x4 framed wall with R-13 insulation will have an R value of 10 - 6 times greater than AAC. So unless you have special requirements that require concrete or brick walls, standard timber framing should be cheaper and better unless you're looking at basement or foundation walls.


In the UK, cavity wall construction for houses is very common. The external skin is generally made from brick, with the internal skin made from "breeze blocks". Breeze blocks are commonly made from aerated concrete!


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.