Locate the damaged sections of the RV roof. Place a pan or bucket in the cabin of the vehicle directly beneath these areas; this will prevent water from soiling the interior during the insulation process.
Scrape any loose or chipping areas of the roof's surface with a putty knife. Properly dispose of the pieces of rubber in a trash bag.
Clean the roof with water and car soap to remove any loose dirt or grime. Scrub the residue with a car wash brush or scouring pad to prepare the surface for the rubber roof application.
Mask off the targeted areas with painter's tape. Apply a smooth, even coat of the EPDM liquid rubber according to the manufacturer's instructions; this step may require a paint roller, brush or special applicator depending on the product.
Verify that the layer of liquid rubber is flush with the rest of the roof. Only a single-coat application is necessary to effectively seal the surface of the roof.
Allow the treated areas to cure for a full 24 hours, preferably in direct sunlight. The repairs are completely dry when the surface feels solid.
