Wood Foundations
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I live in a 25 year old home constructed with a wood foundation. The basement is dry, and insulated on the inside with r-19. To cover the insulation which has been dmaged over the years with holes in the paper covering, I want to cover it with a 6 mil poly. This would be for aestetics only, as the foundation remains solid. With a wood foundation, would a 6 mil interior vapor barrier do any damage that I need to be concerned with.
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Replies
Yes.
If this is what's called an All-Weather Wood Foundation, made from pressure-treated framing and pressure-treated plywood, it will have a vapor barrier on the exterior. Using a double vapor barrier will trap moisture in the wall and cause swelling, possible delamination of the plywood, mold growth if not rot.
Cover the walls with MR (moisture-resistant) drywall or some other moisture-resistant but vapor-permeable material.