A Water Resistive Barrier is a layer installed on the exterior walls of a home to prevent water from penetrating the building’s structure. It acts as a protective shield between the outer cladding (like siding or brick) and the underlying materials, such as sheathing or insulation. WRBs are typically made from materials like house wrap, felt paper, or synthetic membranes and help direct any water that seeps through the outer layer to the exterior, reducing the risk of mold, wood rot, and other moisture-related damage. They are essential for improving the home’s durability and energy efficiency.