TREMproof® 250GC is a rapid-curing, high-solids, modified polyurethane waterproofing membrane that can be applied to damp and green concrete. TREMproof® 250GC is a one-part moisture-curing elastomer. TREMproof® 250GC is a complementary waterproofing membrane that can be used with Tremco's Vegetated Roofing systems. Concrete masonry units and plywood are both acceptable substrates.