How to best use fiberglass batts for insulating a suspended concrete slab
I live in western Wyoming, zone 7. I am building into my uninsulated barn to add a bedroom and mudroom onto my house. The barn is on an existing uninsulated slab. We want to suspend another concrete slab on joists with hydronic heating in the suspended slab.
In preparation for the addition we are tearing down siding and removing existing batt insulation and have a bunch of fiberglass batts left over. I don’t want to throw them out, so I was thinking about using them to insulate under the suspended slab. (we are replacing old batt insulation with flash and fill with 2″ of polyiso board with reverse board and batt siding) Is there a way I can well insulate the floor using the batts, or should I chuck them and use spray foam?
PS. Thank you to everyone for your informative Q & A’s. I have learned so much from this website. Everyone on here helped me design my addition from the insulation, siding, heating, windows, etc…
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