About GAF Silicone Mastic

A thick, high-build silicone sealant featuring low odor, an easy application, a fast moisture cure, and enhanced adhesion to a variety of substrates.

  • A high-solids sealant
  • Low odor
  • Brush grade for easy application
  • Fast moisture cure
  • Enhanced adhesion to a variety of substrates

Features & Benefits

Product Documentation

Resources for every professional


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Whether you manage one property or many, we’re building the products and programs you need to reroof, restore, or maintain your investment.
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