About GAF Bleed-Block Asphalt Primer

GAF Bleed-Block Asphalt Primer is a one part water-based primer designed to block asphaltic bleed through from existing asphaltic roofing systems. GAF Bleed-Block Asphalt primer increases the adhesion of GAF High Solids Silicone over asphaltic assemblies. Bleed-Block Asphalt Primer can be applied by brush, roller, and airless spray equipment.

Features & benefits

Product Documentation

Video playlist thumbnail of a contractor holding a brush treating roofing seams with GAF Silicone Mastic

GAF Silicone Coatings Installation Guide

As an easy-to-apply roof coating, silicone creates a highly flexible and monolithic membrane that offers unrivaled ponding water resistance and excellent UV protection, and won’t degrade, chalk, or crack from prolonged exposure to direct sunlight. Learn installation techniques from the pros.

Commercial roofing products: solutions for every roofing need

From single-ply membranes to full system solutions, and state-of-the-art digital services to hands-on training. GAF other the range of durable, easy-to-use products and services you need to succeed.

Resources for every professional

Contractors

We’re building new plants for greater capacity, and better systems for faster response and greater visibility.
Contractor Resources

Architects & Design Pros

We’re building better, faster, more accurate access to the information you need.
Design Resources

Property managers & owners

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

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