Rockwool Comfortboard 80 Under Radiant Slab?
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Hello,
My builder wants to use Rockwool Comfortboard 80 for insulation under our slab-on-grade for a house in Maine. I’m open to this, and certainly would prefer it over rigid foam, but won’t there be issues with the rockwool compressing – possibly causing cracks in the slab? If anyone has experience with this, I would love some input! [we are also planning in-slab hydronic radiant]
thanks
Brad
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Replies
Brad,
You may find this article useful: https://www.greenbuildingadvisor.com/article/sub-slab-mineral-wool
Thanks, Malcolm. Very helpful!
Brad,
I should have included this more recent one too: https://www.greenbuildingadvisor.com/article/insulating-a-slab-with-rigid-mineral-wool