The CleanSpace Vapor Barrier is a heavy-duty 7 layer, poly reinforced liner with an antimicrobial, UltraFresh, Built in. CleanSpace is installed on the crawl space floor, with seams overlapped and sealed, it is run up the walls 6-8 inches above outside grade and sealed to the walls, and wrapped around all piers and sealed. The CleanSpace system seals your crawl space off from the earth's moisture.