What Is Flat Roof Blistering and How Can You Avoid It?

Roof blisters are a common roofing problem that commercial roofing contractors and property owners encounter. In built-up roofs, blisters are raised surface areas in which air or moisture is trapped. They have an appearance similar to bubbles and when left untreated, can lead to extensive repairs or replacements.

Why Do Flat Roofs Blister?

Roof blisters are caused by many factors including moisture, poor ventilation, and shoddy installation. Blisters typically develop from voids built into the roof. Voids usually result from unintentional skips in bitumen mopping and entrapped debris during the installation process.
Blisters can range from small bubble spots to strikingly large areas, and are more visible on scorching sunny days. When the temperature surrounding the roof surface rises, the pressure inside the blisters builds up, resulting in loss of asphalt adhesion. Although a few small voids can be accommodated by the roofing membrane, the accumulation of large voids will most likely lead to the need for repairs or a roof replacement.

How Do You Fix or Prevent Roof Blisters?

Some roof blisters do not necessarily result in serious roofing issues, provided that they remain watertight and do not expand too largely in size. However, once a blister approaches a dimension of nearly 2 ft., it is recommended to mark its outer boundary so it can be easily inspected. When blisters grow to about 5 ft., they should be repaired immediately.
Prevention is still the best way to avoid having to deal with problems that roof blisters bring. When installing a new roof, make sure that your roof repair contractor is strictly adhering to manufacturer’s specifications and top-notch industry practices. You should also keep your roof cleaned and maintained as well as limit unnecessary foot traffic.
If you need superior quality residential and commercial roofing services, turn to Texas Traditions Roofing. We have a dedicated group of specialists who are more than ready to assist you. Give us a call at (512) 415-4590 or fill out our contact form to schedule a no-obligation consultation. We serve clients in and around Waco, TX.