How Do You Repair An EPDM Roof?

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  • How Do You Repair An EPDM Roof?

Also known as rubber roofs, EPDM roof systems are a common choice for low sloped roofing for residential properties. These roofs have an average life expectancy of between 15 and 20 years. Compared to other roof systems that utilize hot asphalt or an open flame, EPDM roofs are safer. Additionally, they are easier to repair and maintain if leaks or other forms of damages occur. When it comes to repairing such roofs, here are some basic steps to keep in mind:

Step One: Prepare and Clean the Area that Needs to be Repaired

EPDM contains carbon within its membrane due to the layer’s aging effects. If you try rubbing your hand across the sheet, you will see carbon black particles (i.e. oxidized particles and dirt) on your hand’s surface. That’s why the surfaces of these sheets must be thoroughly cleaned. This ensures that the repair patch sticks to the roof membrane’s surface without problems. It is important to use cleaning solutions that do not leave residues behind. If you clean and remove all of the mentioned impurities, you can expect to enjoy long-term performance.

Step Two: Size and Cut the Repair Patch

Before applying the primer, measuring the roof repair patch is pertinent. Lay it over the area that needs to be patched. Outline the patch with a two-inch allowance around the perimeter. It should extend beyond the damaged area, in all directions. After that, you can proceed to cut out the repair material. Remember to clip or round the corners of the patch. Sharp corners tend to be lifted or caught by foot traffic.

Step Three: Get Ready for the Priming Process

The surface of the membrane, where the roof repair patch is to be applied, requires a thin coat of primer. You can apply the primer by using a paintbrush or paint roller (preferably medium-nap). When you apply the primer, make sure that you go past the edges of where the patch is to be applied. This is a popular technique that helps ensure that all the leading edges of the repair patch adhere to the roof membrane.

Step Four: Repair Patch Installation

Never use yellow glue to adhere non-pressure-sensitive backing. The adhesive needs to be made for sealing EPDM-to-EPDM materials. For example, a single-ply EPDM adhesive. For pressure-sensitive roof repair patches, it is recommended that you use a steel roller to apply the patch. In addition, you must remove the film or paper backing from the patch. After applying firmly on the surface, proceed to press any trapped air out. The adhesive should flash off to the point it is no longer tacky to the touch. It is a good idea to also use EPDM lap sealant. Just apply a bead of the product. It should be used around the leading edges of the patch. This prevents water infiltration from causing further damage.


EPDM roofing membranes are not compatible with asphalt-based products. Asphalt-based roof coatings can contaminate synthetic rubber membranes to a point where the entire roof system needs to be replaced.

Alternatively, you can leave these tasks to professional roof repair specialists. They can make sure that everything is done correctly, which minimizes both near- and long-term costs related to roof repair and maintenance.