EFF-STOP® Premium Interior/Exterior Masonry Primer Sealer

EFF-STOP® Premium is an epoxy-fortified acrylic primer/sealer engineered for interior and exterior masonry surfaces where alkalinity, efflorescence, and surface moisture would otherwise compromise topcoat performance. Suitable for tilt-up concrete, poured-in-place concrete, stucco, and block, the product bonds tightly to substrates with a pH range of 6 to 13 — well above the range tolerated by conventional primers.

The hybrid acrylic/epoxy resin chemistry resists efflorescence blooms and locks down soluble salts, producing a clean, uniform surface for finish coats. With low VOC content (50 g/L) and soap-and-water cleanup, EFF-STOP® Premium is widely specified across commercial, institutional, and multi-family masonry projects in the Southwest and beyond.