Common Reasons for Seal Failure in Membrane Roofs

Single-ply membrane roofs are a common choice in commercial roofing applications. Examples include thermoplastic olefin (TPO), ethylene propylene diene monomer (EPDM), polyvinyl chloride (PVC) and modified bitumen. Installation methods vary between them, but they do have one thing in common – they’re sealed at the seams using heat or adhesive. 

However, it’s the seams that make membrane material vulnerable to failure. They are, after all, the weakest part of the roofing system. Here are the common reasons for seal failure in membrane roofs.

Ultraviolet Exposure

Long-term exposure to the sun’s ultraviolet (UV) rays causes membrane roofs to dry and become brittle. This, in turn, causes the seams to open up and create gaps. The same can happen when the material is exposed to extreme temperature changes, which leads to shrinkage. The seams may have strong adhesives applied on them, but the rest of the roof may be too weak that it may tear apart, exposing the whole system to the elements. Applying coatings to help curb the effects of UV rays can prolong the life span of membrane roofs.

Lack of Insulation

The insulation on a single-ply membrane roof may not be enough to keep the entire system intact. If this is the case, then expect humps across the roof surface, which loosen the applied adhesive. This, unfortunately, is difficult to repair, so to avoid this problem, you have to make sure there’s adequate attic insulation installed during the roof replacement process.

Poor Workmanship

Seam failure is likely to occur if there’s evidence of poor workmanship. The seams must be welded together properly using either heat or adhesive, taking into account temperature and surface coverage to minimize weak spots. If not observed, the roof may deteriorate and let in moisture. Be sure the contractor you hire has the skills and experience to follow proper installation procedures. The last thing you want is a roof that needs frequent but costly repairs.

Done-Right Roofing & Sheet Metal Ltd. specializes in high-quality residential and commercial roofing services as well as other home improvement services, such as vinyl siding and soffit installations. Get in touch with us today by calling (905) 875-2888 or filling out this contact form.