CertainTeed's Flintlastic Ultra Glass SA is designed for use as a base sheet for modified bitumen roofing systems. It is suitable for use in the construction of various types of membranes for both new construction and reroofing, over a variety of substrates. Flintlastic Ultra Glass SA will provide additional strength, improved handling, pliability, and moisture resistance when used as the first ply over insulated substrates and non-nailable.