Over Concrete

Structural concrete roofs need a coating system that bonds to a high-pH, often damp substrate and stays watertight through thermal cycling. The Premium Acrylic HydroStop system on concrete uses Epoxy Primer, then a fabric-embedded base coat (a same-day second coat is skipped to let the concrete breathe), then top coat. Wind uplift tested at -610 PSF, well above asphaltic or single-ply alternatives.

For lightweight concrete decks, NOA 23-0327.10 specifies BarrierGuard Surface Coating plus SureBond Primer before the HydroStop system. For below-grade or overburden waterproofing (balconies, plazas, tile-over), Surface Seal SB is the thermoplastic rubber answer. For concrete roofs with ponding, GAF High Solids Silicone over Multi-Purpose Primer is the warranted path. Factory-direct from a GAF-authorized distributor.