How should I insulate my basement walls?
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I live in northwestern South Carolina. I am finishing a basement and am planning to coat the block walls with a good damp-proofing product and then glue 1-2″ of rigid foam insulation on top of that. I plan to leave a small airspace between the rigid foam and my stud wall, which will be finished with sheetrock The ceiling will not be insulated. I have two questions:
1. Is this a good overall plan?
2. Should I still insulate the stud wall with fiberglass batt insulation?
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Replies
Simon,
Q. "Is this a good overall plan?"
A. Yes, although more insulation is always better than less -- you could always install 3 inches.
Q. "Should I still insulate the stud wall with fiberglass batt insulation?"
A. No. Fiberglass batts should never be installed on a basement wall, because they perform poorly in a damp environment.
Simon,
You and Martin have it exactly right, this is the safe way to insulate a basement wall.