Hardcast® True Mastic Sealant Tapes

Hardcast true mastic sealant tapes are a high-performance alternative to traditional liquid sealants. Hardcast Foil Grip™ tapes deliver an instant, airtight seal with no cure time, mess, or VOCs. Featuring a thick butyl mastic with high tensile strength, Hardcast Foil Grip tapes bond instantly to surfaces and deliver long-term thermal performance, even under pressure.

As a code compliant solution, Foil Grip tapes are ideal for HVAC system installs, retrofits, and changeouts.

Why Switch from Liquid Mastic to Rolled Mastic?

Traditional bucket and brush methods rely on slow-curing, time-intensive liquid mastics that are often unevenly applied in varying thicknesses and crack over time. Hardcast mastic tapes (Foil Grip 1402, 1403, & 1404 181BFX) are different. Made of high-performance 15 mil butyl adhesive backed by a 2 mil foil facer, Hardcast rolled mastic tapes bond immediately to duct surfaces and maintain long-term performance across commercial, industrial, and residential applications. Their tensile strength, flexibility, and durability are far superior to standard duct tapes. The seal bridges surface imperfections and conforms around angles and over fasteners without tearing. Each tape deploys consistent mil thickness and strong adhesion to metal, flex duct, and PVC-coated surfaces.

Benefits

• Air-tight Seal Without Mess or Wait Time: Pressure-sensitive design, bonds instantly with no cure time.
• Built for Performance: Delivers tensile strength of up to 1,400 psi.
• Code Compliant: Passes code inspection requirements.
• Durable: Reinforced construction bridges imperfections, gaps, and over fasteners without tearing.
• Resilient: Sturdy construction that resists water, UV rays.
• Eco-Friendly: Zero VOCs and no off gassing.

Engineered for Installs, Retrofits, Changeouts

Hardcast true mastic tapes help contractors achieve airtight, code-compliant results across HVAC applications from sealing transitions between new air handlers and existing ductwork to sealing Pittsburgh seams and transverse joints.

Hardcast Mastic Tapes Product Options

Ready to Roll?

Replace liquid mastic with an easy-to-apply tape to save time and deliver more consistent, durable results. Order Hardcast Rolled Sealants from your preferred HVAC supplier.