TREMproof 250GC is a rapid-curing, high-solids, VOC-compliant modified polyurethane waterproofing membrane that can be applied to damp and green concrete. TREMproof 250GC is a one-part moisture-curing elastomer available in three viscosities: Self-Leveling (SL), Roller (R), and Trowel (trowel intended for detailing work only).