ENERFOAM professional foam sealant is designed to form a durable, airtight, water-resistant bond to common building substrates such as wood, brick, concrete, foam board and most plastics. Its foam skin repels and deflects water, which can help reduce the potential for moisture damage to wood substrates. It is a one-component, minimal expanding, flexible polyurethane foam used for adhering insulated concrete forms, architectural foam and drywall and sealing cracks and voids such as pipe penetrations. The foam expands only enough to generate an effective seal, retaining elasticity as the structure expands and compresses. ENERFOAM professional foam sealant is also recognized as a fireblock, which means it resists the free passage of flames to other areas of the building through concealed spaces.