DIY: Additional Vapor Barrier with Faced Insulation? [solved]
When installing faced insulation into exterior walls, are there any benefits or detriments to adding an additional vapor barrier to either the non-faced side of the insulation?
why is this a community wiki? - mohlsen 12 years ago
not 100% certain on this, but a double vapor barrier will actually cause harm as the moisture will have no where to escape to. Especially if you place it on the non-faced side. If you place it on the already faced side, it probably wont hurt, but is pointless as you already have the barrier .
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