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

GEMCOAT™ enhances and deepens the beauty and color of the aggregates within the masonry unit, and is the same sealer that is 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.
2. Let stand for a minimum of 15 minutes.

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

Download Product Data Sheets