Issues Common With Modified Bitumen Roofing Systems

Posted on: 3 August 2022

Before settling on a roofing system for your commercial property, you need to sit down and narrow down the options available, then consider the associated challenges. This way, you can make a more informed decision and engage a professional on ways to mitigate the said roofing issues. For example, you might encounter issues common with the modified bitumen (MB) roofing option. But first, you may want to know what they are. For starters, like BUR roofs, modified bitumen roofing systems are made of layers of asphalt and reinforced using polyester and rubber modifiers. Some benefits of installing MB include energy efficacy, flexibility, tear resistance, and waterproofing.

Here are repairs you may encounter with this kind of roofing.


One of the things you will notice when your commercial roofer comes over to inspect your bitumen roofing is they will insist on trimming nearby trees. This is because falling limbs leave punctures. Your roof may also develop punctures from foot traffic when workers frequent the door on the roof. As a result, the roof may develop cuts and damage to the underlayment. Lastly, vibrations from heavy mechanical equipment can cause the fasteners to come off and puncture the surface. With this information, roof inspections will help catch issues early enough.

Seam Issues

Modified bitumen roofing installations are quite different from others in that they are done in long sections a few inches wide. Each of these sections is then stuck to each other using a lap several inches thick. But too much thermal or stress can cause the seam to fail or form voids along the laps. It would help if you avoided DIY installations and if one has already happened, contact an experienced roofer to repair and rectify the errors incurred during the process. 

Wrinkling and Blistering

Your roof may also wrinkle due to several reasons. The first, mostly associated with DIY installations, is when you fail to roll or press the membrane properly, so it ends up not sticking properly onto the adhesive. The same issue may arise if moisture is trapped underneath, which is one of the main causes of the blisters. Therefore, it would be best if you contact a commercial roofer for repairs to avoid leaks. 

Modified bitumen roofing systems have excellent waterproofing properties when properly installed and can last long. However, to avoid any of the above-mentioned issues, always hire a qualified commercial roofer to take care of everything from installations to repairs and maintenance.

Reach out to a company like Rayburn1 Roofing, Solar & Windows to learn more.