Carlisle SynTec also offers Sure-Flex™ PVC, a highly reflective, heat-weldable single-ply roofing membrane. Sure-Flex membranes are available in 50-, 60- and 80-mil thicknesses, offering a durable roof system that can withstand harsh weather conditions and long-term exposure to rooftop contaminants. Sure-Flex membranes are CRRC certified, helping reduce a building’s air conditioning costs and meeting all of the requirements for California’s Title 24.