No Vapor Retarders on Interior Side of Air-Permeable Foundation Insulation Description Vapor retarder plastic should not be installed over fibrous insulation on basement or crawlspace walls unless rigid foam or spray foam is installed directly against the concrete, behind the blanket insulation.
Image The below-grade wall assembly includes dampproofing, draining details, and insulation. Publication Date Tue, 05/01/2012 - 12:00
Image Wrong - Class I vapor retarder over framed basement walls can cause condensation, mold, and rotting because plastic prevents drying to the inside; the outside should have waterproofing and vertical drainage, and the framing should be spaced from the wall. Publication Date Thu, 03/01/2012 - 12:00
