Learning About Roofing Services

How To Fix A Seam On A Rubber Roof

If you have a rubber roof, weather exposure can weaken or separate the membrane seam causing leaks. Rubber roofs are commonly used on flat roofs. They are comprised of multiple rubber mats joined together by seam tape at the flap of the top sheet. You should be able to repair the seams on your own. Here are some tips to repair rubber roof seams.

Prepare to Work

For this project, you need:

  • extension ladder
  • safety harness
  • rubber gloves
  • felt-tip marker
  • broom
  • towel
  • EPDM (ethylene propylene diene monomer) cleaner
  • warm water
  • paint brush
  • 2-inch silicone hand roller
  • seam probe tool
  • EPDM seam tape
  • primer activator adhesive

Set a ladder on a flat surface, and get someone to hold it for you. Locate separated seams; paying attention to vents and pipes, but be careful walking on rubber. Debris may puncture the roof.

Mark the separated seams with a felt-tip marker. Sweep debris from the roof, then remove old adhesive with a towel, EPDM cleaner, and warm water. Pull the seams apart about twelve inches, clean adhesive on the inside and bottom, if necessary, and let the area dry.

Apply the Adhesive

Use the paint brush to apply primer activator adhesive where the flap will rest on another mat. Apply the adhesive in six-inch wide areas on the top and bottom, making sure it reaches the corners. Push the seams together, then run a silicone roller on the seam to remove air bubbles.

Let the adhesive dry for 24 hours. Insert a seam probe tool into the exterior seam edge to test if the adhesive has cured. If you can easily insert the seam probe into the seam, the adhesive has not properly set. Add more adhesive, and repeat this step.

Install the Seam Tape

Place the seam tape on the seam, remove the wax coating from the back of the roll, and push it down. Use the 2-inch roller to press it down further, or walk on the seam.

Set the seam flap on the other side of the tape, and start removing the wax coating; pulling the tape from below the seam flap. The tape doesn't have to be secure yet.  It just has to be in place.

Repeat until the seam is covered, then press the seam flap with the 2-inch roller. Run the roller down the length of the flap and the entire seam at a 90-degree angle.

Watch the roof for leaks the next time it rains. If it leaks,or you don't trust your skill, hire a commercial roofing contractor.