Ethylene propylene diene monomer (EPDM) and modified bitumen roofs are known for their exceptional durability. However, both types of roofing systems suffer from a common problem: roof shrinkage, which pulls at the roof flashing and, in the process, creates openings for moisture to infiltrate the roof.
Fortunately, manufacturers have made several improvements to modern EPDM and modified bitumen roofs to reduce the risk of shrinkage, but that doesn’t mean they’re immune to roof shrinkage. Here are some of the causes.

Rushed Installation Process
It’s never a good idea to rush a roof replacement. For instance, modified bitumen should be laid out 45 minutes before the start of the installation. Otherwise, the flat roof will be highly vulnerable to shrinkage.
Fortunately, you shouldn’t have to worry about a rushed roofing installation if you hire a professional contractor. The only reason roofing contractors would rush a roofing installation is that they’re looking to finish as many installations as possible, something which storm chasers usually do.
Faulty Roof Design
A qualified roofer would compensate for roof shrinkage in the roof design and install elements that can combat shrinkage like drain vents for instance.
Low-Quality Roofing Membranes
Even if an EPDM or modified bitumen roofing system was installed properly, it won’t last long if it’s made of low-quality materials. This is the same reason why you should be wary of low roofing bids. It might be tempting to hire the roofers with the lowest bid, but it’s likely that they cut corners on the quality of roofing materials. Remember: if a roofing bid good to be true, then it probably is.
Aging
As rubber membranes age, they become less elastic. As such, in some cases, roof shrinkage may be a sign you need a commercial roof replacement. To ensure roof repair and installations are done properly, make sure to vet roofers before hiring them.
Looking for professional roofers near you?
Total Roof Services Corp., a GAF Master Elite® roofer, offers a wide range of professional roofing services, including emergency roof repair services. To schedule a free consultation, call us at (407) 495-4151, or fill out this form.