Henry #203 Cold Process Roof Cement is a premium, brush or squeegee-grade waterproof adhesive engineered for built-up roofing (BUR) applications. This cold-applied formula eliminates the burn and fire risks associated with hot asphalt while delivering superior cohesive strength and flexibility—even in colder weather. Ideal for roofers seeking a reliable, UL-classified solution, Henry #203 bonds asphalt-coated base sheets, mineral-surfaced cap sheets, polyester fabrics and more to create a durable, watertight roof system.

Formulated from high-grade asphalt, solvents and organic fibers, this one-gallon pail offers consistent coverage and easy spreadability. Apply with a notched squeegee or 4-knot roofing brush to achieve a uniform bond. Whether you’re installing new layers or reinforcing existing membranes, Henry #203 provides cold-process convenience without sacrificing performance.

Key Features

• Premium brush* or squeegee-grade, cold-process formula
• Waterproof adhesive made from asphalt, solvents and organic fibers
• Replaces hot asphalt in built-up roofing applications
• Eliminates burn and fire hazards of hot asphalt
• Outstanding cohesive strength and cold-weather flexibility
• Bonds 25 lb. or heavier asphalt-coated fiberglass base sheets, mineral-surfaced cap sheets and polyester fabrics
• Apply with notched squeegee or 4-knot roofing brush
• UL classified for Class A and B fire-rated roof systems
• Conforms to ASTM D-3019 Type III

⚠️ WARNING: This product can expose you to Benz[a]anthracene known to the State of California to cause cancer. For more information, visit www.P65Warnings.ca.gov.

⚠️ WARNING: This product can expose you to polycyclic aromatic compounds (possibly present in asphalt in trace amounts) which are known to the State of California to cause cancer. For more information, visit www.P65Warnings.ca.gov.