SRP Membranes keep water out while allowing water vapour to escape rapidly. They are installed in sloped roofing systems and wall cladding systems to improve their durability and performance by promoting rapid drying. In sloped roofing install SRP under the primary roofing as a secondary drainage plane or roof underlayment. In wall cladding systems, SRP acts as a sheathing membrane, secondary drainage plane, air barrier and in the case of open joint systems, as an aesthetic blackout membrane.