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How should I insulate my basement walls?

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?

Asked by simon Bender
Posted Mar 18, 2011 1:02 PM ET


2 Answers

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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.

Answered by Martin Holladay, GBA Advisor
Posted Mar 19, 2011 7:33 AM ET



You and Martin have it exactly right, this is the safe way to insulate a basement wall.

Answered by Doug McEvers
Posted Mar 19, 2011 9:56 AM ET

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