Rubber roofs are built to last, with a life expectancy of 15 to 20 years. Minor repairs, if needed, can usually be handled by dedicated amateurs.
While installing a rubber roof is tricky enough to require professional roofers, minor repairs are easily handled for the DIYer armed with the right tools and knowledge.
First, you need to know what kind of roof covering you have. You should be able to determine this from the ground. (Keep in mind that a flat roof covered with EDPM (ethylene propylene diene monomer) rubber is a far different beast than a hot-tar-and-gravel one. If you use asphalt-based products, like an asphalt roof coating, not only will the repair not work, you might cause even more damage.) Visit your local building centre to buy what you’ll need: a scraper to remove old caulking, patch material, EDPM primer, and a paintbrush or roller.
Clean the surface
After you find and mark the problem you need to patch, sweep the area free of dirt and debris, removing any old caulking material with a scraper. To really remove any dirt as well as any oxidization and the carbon film that usually forms on EDPM roofs, use a cleaner that won’t leave a residue after drying.
It’s important that you remove all dirt, carbon, and oxidization, or you risk the patch not properly adhering to the roof surface. Allow the area to dry before continuing.
Cut the roof repair patch to size
Lay the rubber roof repair patch over the damaged area to measure what size you’ll need. The material should extend at least 5 cm beyond the edge of the affected area. With scissors, cut the patch to size and round its corners to avoid leaving a sharp edge or anything that can be caught and lifted up by a foot.
Apply the primer
Using a paintbrush or paint roller, apply an even coat of EDPM primer, ensuring that it also extends at least 5 cm past the edge of the tear or cut in the rubber membrane. The primer ensures that the patch will correctly adhere to the roof.
Install the patch
Patches come either as standard membrane materials, requiring separate adhesive, or pressure-sensitive ones, with adhesive already applied to its underside. With the former, you’ll require a single-ply EDPM adhesive, applying it to the patch and the repair area of the roof. (The adhesive should be one used for sealing EDPM to EDPM, and not to substrates or insulation board.)
In the latter case, remove the backing material from the patch and then smooth it over the affected area slowly, working from one end to another.
With either kind, press down on the patch to remove air pockets and then use a hand roller over its entire area to ensure it adheres properly to the roof.
