Great Stuff 12 oz. Fireblock Insulating Foam Sealant is a high-performance, ready-to-use spray foam designed to seal gaps, cracks and penetrations up to ¾″. Formulated to provide both insulation and a fire‐blocking barrier, this vibrant orange sealant expands minimally to fill voids without over‐pressurizing surrounding materials. Ideal for electrical, plumbing and HVAC applications, it helps impede the spread of fire and smoke through walls, floors and ceilings while reducing air infiltration and energy loss.

Whether you’re a professional contractor or a DIY enthusiast, this foam sealant delivers reliable results indoors and outdoors. It bonds to wood, metal, masonry, glass and most plastics, offering moisture resistance and long‐term durability in a wide range of environmental conditions.

Key Features

• Ready‐to‐use aerosol can—no mixing or extra tools required
• Minimal expansion formula—fills gaps cleanly and precisely
• Fire and smoke resistant—tested to ASTM E84 standards
• Moisture resistant—maintains bond and performance over time
• Broad adhesion—sticks to wood, metal, masonry, glass and plastics
• High coverage—up to 495 linear feet per 12 oz. can (¼″ bead)
• Fast curing—reaches handling strength in just 8 hours
• Long shelf life—stores up to 18 months unopened