ᐅ 80 mm insulation below the slab or 120 mm insulation above the slab

Created on: 20 Oct 2014 09:37
B
blaumann
B
blaumann
20 Oct 2014 09:37
Hello house building community,

I have noticed that different construction descriptions mention different types of floor insulation.

On one hand, there is the under-slab insulation (80mm (3 inches)) and on the other hand, the above-slab insulation (120mm (5 inches)).

Which type of insulation makes more sense?

I’m looking forward to your answers.

Best regards
K1300S23 Oct 2014 09:08
Both make sense because both provide insulation. ;-)

I once read that it depends on the wall structure—whether the vertical insulation ends at the base slab (as is the case, for example, with filled clay bricks) or can extend beyond it (for instance, with an external thermal insulation composite system, ETICS). In the first case, in my opinion, insulation on top of the footing makes sense; in the latter case, insulation under the footing is more appropriate. However, both options are possible in any case.

Good luck

K1300S