Great Stuff Big Gap Filler Insulating Foam Sealant

Great Stuff Big Gap Filler Insulating Foam Sealant is a professional-grade expanding polyurethane foam designed to fill, seal, and insulate gaps up to 3 inches wide. Perfect for both indoor and outdoor use, it forms a durable, airtight, and water-resistant barrier that prevents drafts, pests, and moisture from entering your home. Once applied, the foam expands to fill large voids and hardens into a rigid, closed-cell structure that provides excellent insulation and long-lasting stability. Ideal for sealing around plumbing penetrations, electrical outlets, basement rim joists, window and door frames, and attic openings, it helps improve overall energy efficiency and comfort. The precision straw applicator ensures easy, controlled dispensing with minimal waste. Once cured, the foam can be trimmed, sanded, painted, or stained to match surrounding surfaces. Trusted by homeowners and professionals alike, Great Stuff Big Gap Filler is a simple yet powerful solution for sealing and insulating large openings to make any home more efficient and secure.