Turn the space under your deck into a dry, usable area with this HDPE waterproofing membrane. This 50-foot roll is designed for decks with 16-inch joist spacing and works as part of a complete under-deck drainage system. Made from high-density polyethylene, it’s tear-resistant, UV-protected, and blocks water effectively. It’s lightweight, easy to cut and install, and helps prevent leaks so you can create a cozy patio, storage area, or entertainment spot below your deck. For a full system, pair it with downspouts and other components. Need a custom design? Reach out—they offer free deck system planning!
