PROCEIL 20 is a 20 mil HDPE Vapor Barrier with an adhesive that Forms an integral seal to the underside of concrete slabs. Once the seams are fully taped, you have a monolithic membrane that will protect floor finishes such as wood, tiles, carpet and resilient flooring from damage by vapor transmission and water intrusion. PROCEIL 20 Remains sealed to the slab even if the ground underneath settles.