Insulating a Slab on Grade and Moisture Control
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I recently purchased an older home (1977) slab on grade with no insulation or vapor barrier under the slab, in fact it was poured on loose shell rock. I found all the tack strips on the outside walls have been wet and are almost rotted and I can smell mildew on the carpet edges when I pulled it up to paint. I’ve done lots of reading and can’t find a solid answer so: how do I stop the moisture from coming in and insulate the floor under the carpet and the bottom around the outside?
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Replies
It might be from condensation and not moisture intrusion. The carpet acts as a slight insulation layer keeping the slab cool enough to condense the humidity in the room.
Do a search on here for insulating basement floors for ideas on how to stop this.
There are a number of details here that you might want to consider for your situation: Building Plans for Energy Efficient Basement Remodeling.