A single-ply membrane is a polymer-based roofing material that provides a waterproofing layer in a single sheet. The system is sealed at the joints with heat, adhesive, or by mechanical means. It can be adhered, mechanically attached, and or ballasted in a flat or pitched roof system. Single-ply membranes include TPO, PVC, and EPDM. These membranes are cost effective they are flexible, light weight, and fast to install, making them increasingly popular for new build and re-roof applications.