The Cav-Air-Ator protects against moisture issues in masonry applications by providing an unobstructed air space for drainage and ventilation. The product is a full wall drainage and ventilation mat for full brick or stone masonry walls. It prevents mortar from entering the cavity, clinging to wall ties or blocking weep holes. The design allows it to be light and flexible so that the wall ties that it rests on top of can support it. The Cav-Air-Ator is made up of an extruded polymer matrix of entangled monofilaments that form block-shaped channels. In masonry walls, it leaves 96.5 percent of the cavity unobstructed and free to breathe. A lightweight filtered fabric is laminated on one side of the product to prevent mortar from entering the cavity while still allowing enough finger room to lay the brick. The high airflow and lack of mortar intrusion allows efficient liquid moisture drainage and uniform airflow in all directions.