Technical Information
Willseal® Seismic is a pre-compressed, self-expanding foam expansion joint seal designed for vertical building joints, seismic joints, façade joints, and EIFS movement joints. Made with open-cell foam impregnated with hydrophobic acrylic polymer and finished with a factory-applied silicone sealant face, it provides watertight protection while accommodating ±50% movement. Willseal Seismic is ideal for exterior wall joints, seismic expansion joints, vertical waterproofing details, EIFS systems, cladding joints, and building movement joints requiring non-invasive anchoring and long-term weather protection.