GEMCOAT™ water-resistant sealer represents an innovation for enhancing our premium architectural masonry units. It is a liquid membrane sealer made of a 100% acrylic polymer formulation that creates a full-gloss finish that protects and improves the appearance of architectural blocks.

GEMCOAT enhances and deepens the beauty and color of the aggregates within the masonry unit and is the same sealer applied to our block units during production.

GEMCOAT is resistant to liquids yet is vapor/air permeable. It provides excellent protection from the elements, such as water, alkalis, acids, air-borne pollutants, and ultraviolet light, without losing the clear gloss finish.



  • Full-gloss finish
  • Fast drying: dry to the touch in 10 to 15 minutes
  • Water resistant, yet vapor and air permeable
  • Meets most state and federal VOC requirements
  • Cleanable with commercially available surface cleaners
  • Low film build application: 5 wet mils max



  1. Substrate must be dry and clean of oil and dirt.
  2. Apply GEMCOAT using a soft brush, roller or spray.
  3. Let stand for a minimum of 15 minutes.

Available in 5 gal. pails, with EZ-Pour spout.