What does a Blister in roofing indicate?

A blister in roofing is a raised area that forms due to internal pressure, which typically results from trapped moisture or air beneath the roofing material. This phenomenon occurs when the roofing membrane becomes compromised, allowing air or water to become trapped during the installation process or over time due to environmental factors. As temperatures rise, the trapped air or vapor expands, causing the material to bulge outward, creating a visible blister on the surface.

Recognizing a blister is crucial because it can indicate potential failures in the roofing system. If left unaddressed, blisters can lead to further deterioration, including leaks or the eventual lifting of the membrane. Understanding this helps roofers and building owners to take preventive measures or perform necessary repairs to maintain the integrity of the roofing system.