8 lb Expanding Polyurethane Pour Foam – High-Density Marine & Structural FoamOur 8 lb Expanding Polyurethane Pour Foam is a premium, closed-cell structural foam designed for heavy-duty marine, construction, industrial, and automotive applications. When mixed, this two-part pour foam expands to create a dense, rigid, waterproof core that won’t shrink, absorb moisture, or break down over time. It delivers superior strength for boat hulls, stringers, flotation, void filling, mold reinforcement, dock supports, concrete stabilization, and more.Engineered for high-load environments, the 8 lb density foam offers significantly stronger compression resistance than lighter grades (2 lb, 4 lb, or 6 lb), making it ideal for structural repairs and load-bearing support. Once cured, it can be cut, sanded, drilled, painted, fiberglassed, or coated, making it versatile for both professional and DIY projects.