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USG Durock™ Brand Primer-Sealer is a fast-drying, high-solids, low VOC, acrylic primer used for priming substrates prior to the application of USG Durock™ Brand Self-Leveling Underlayments. Ready to use (no dilution for nonporous surfaces), USG Durock™ Primer-Sealer is a single-coat application product, suitable for applications over well bonded, sound, stable and clean existing floor coverings that are on concrete subfloors such as ceramic tile, vinyl composition tile (VCT), cement terrazzo and thin cutback adhesive. USG Durock™ Primer-Sealer can also be diluted with water to prime highly porous concrete, precast concrete, APA-Rated exterior glue plywood, oriented strand board (OSB) and USG Structural Panels. This product is available in 1-gallon jugs and 5-gallon pails from USG’s Gypsum, OH facility. Note that coatings typically assessed using the PCR for resinous floor coatings include additional coating layers (i.e. basecoat and topcoat) beyond those manufactured by USG