Certified as a Class 1 vapor retarder, the Pro Crawl Barrier ensures high performance at an affordable price, making it a trusted option for both first-time installations and upgrades. Certified ...
A Class II vapor retarder should be placed over a wood subfloor and below the wood flooring when being installed over an unconditioned space. Do not use asphalt- or bitumen-type vapor retarders ...
First, it must be determined whether or not a vapor retarder is present beneath the slab, and if it was placed correctly (i.e., directly below the concrete slab and above any earthen material).