What is the best way to insulate basement exterior walls that have a minor problem with condensation?
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This house is in the Philadelphia area and the foundation walls are constructed with CMU. The condensation occurs intermittently in the springtime months.
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Replies
DJ,
You need to install interior insulation. Your best choices are rigid EPS foam, rigid polyiso foam, or closed-cell spray polyurethane foam.
In your climate zone (either zone 4 or zone 5), the 2006 IRC calls for a minimum of R-10. That means about 3 inches of EPS, or about 2 inches of polyiso or closed-cell spray foam.