Broken EPDM Roof Seams - Why They Happen And How To Fix Them

Posted on: 11 August 2016

If you have a commercial flat roof, then you may have an EPDM variety on the top of your business. These roofs are made from synthetic rubber membranes. Specifically, the roof is made from ethylene propylene diene monomer. EPDM is a standard roofing material that is installed in large sheets. The synthetic material is ideal for commercial roofing purposes because it remains strong against UV radiation, thermal damage, and extreme weather conditions. The roofing material is not impervious to damage though, so you will need to inspect your roof on a regular basis to make sure that it is free of issues. There are several common problems you may see, like broken seams. Keep reading to understand why broken seams occur and how you can make a repair.

Why Do Seams Pull Up?

EPDM roofs are formed out of long and wide strips of synthetic rubber. The long strips help to reduce the number of seams that appear across the surface of the flat roof. The seams that are present will need to be glued down. However, the seams can pull back up. This can happen for several different reasons. A rubber roof will expand and contract as it becomes warm or cold. This can place pressure on the seams and cause them to loosen. Also, the seam adhesion process can make the seams weaker than they should be.

Optimal conditions are needed to seal the seams. Outdoor weather cannot be too hot, cold, or humid. Also, preparation that includes the chemical cleaning and priming of the seam must occur before contact cement is brushed into place. Contact cement must dry a small amount as well before the two sides of the seam are secured together. This means there are many points of potential error when closing seams. 

Seams should be repaired as soon as a broken one is noticed, or water can seep under the seam and cause a leak. Extensive leaks may require the complete replacement of an EPDM strip, so it is wise to make the fix before a major repair is needed.

How Do You Repair A Seam?

If you notice a seam that has pulled apart, then you will need to repair the area. Purchase a small container of EPDM bonding adhesive from your local home store. You will also need a small paintbrush, some EPDM cover tape, lap sealant, and solvent-resistant gloves.

Use a broom to remove the debris from the pulled-up seam and put the solvent-resistant gloves on your hands. Open the container of bonding adhesive and use your paintbrush to apply a thin layer of the material along the upper and lower areas of the open seam. The adhesive is a solvent based material that needs to dry for several minutes so that it is tacky before the seam is pushed together. Let the sealant dry for several minutes and then use your gloved finger to gently touch the glue to see if it is sticky. If it is, then press down on the seam to close the opening. 

Use a weighted roller over the seam to make sure both sides of the EPDM rubber stick together. Once the adhesive is secured, you will want to protect the area from future seam issues. An open seam is a weakness in the roof that may pull apart again in the future. Prevent this problem by cutting a piece of EPDM cover tape that is about two feet larger than the split in the seam. Place your lap sealant in a caulk gun and spread a thick layer of the material across the top of the seam. Place the tape over the sealant and use your weighted roller to secure the sealant to the tape. 

For more information and advice, contact a company like Fischer Roofing - Flat Roof Pros.


A Direct Guide To Roofing

Hi, my name is Scott, and as you search through this blog, you'll learn invaluable information concerning roofs. When reading the articles, you'll learn about roof repairs, roofing materials and what's new in the roofing industry. I didn't become interested in roofing until my roof started to leak. When that happened, I started doing all types of research to find out why and where my roof was leaking. As I performed my research, I became very interested in the entire industry and even after I hired professional roofers to fix the leak, I still wanted to learn more about roofing. Since I enjoy blogging in my spare time, I decided to start a blog about roofing, and I hope that you also find the information you read interesting and useful.