The DuPont Tyvek Fluid Applied WB+ System is made using a silyl-terminated polyether (STPE) and can be sprayed or pressure-rolled on to help protect building envelopes from air and bulk-water infiltration. DuPont says the material provides more coverage per gallon than older, acrylic and bitumen-based products. The company also says the material experiences minimal shrinking or cracking while curing, can be applied to concrete or gypsum, withstands nine months of UV exposure, and is vapor permeable. Check with local distributors for price.