Ensure a drier home with Delta-Vent S, a fully waterproof roof underlayment designed to help the home breathe and dry. For use on insulated, pitched roofs, Delta-Vent S features vapor permeability that lets residual moisture from inside the home migrate through to the outdoors, so that thermal insulation stays dry and performs as intended. Because of its low weight per square yard, the material can be unrolled fast and flush without any distortion or buckling, the maker says. 905.563.3255. www.cosella-dorken.com.