A joint sealant for building walls and wall systems, Backerseal is an economical, precompressed, secondary joint sealant to field-applied caulking. Backerseal is a polyurethane foam infused with a hydrophobic-acrylic impregnation technology.
Unlike ‘double caulk and backer rod’, Backerseal behind field-applied liquid sealants provides true “belt and suspenders” sealing–two systems working on different principles to perform the same function. ‘Double caulk and backer rod’ is very difficult to install to achieve the geometry necessary to function in moving joints. In addition, the same forces (tensile stresses at the bondline and within the cured sealant) that will cause the outer installation to fail, will also likely cause the inner installation to fail as well. Backerseal works in compression providing a practical-to-install, fully functional secondary joint sealant using different performance principles than the primary, liquid sealant. Additionally Backerseal provides insulation and sound attenuation value as well as the ability to resist the effects of air-pressure differentials.