Asphalt Shingle Blisters: What Causes Them?

Asphalt shingle roofing manufacturing has advanced to the point where problems arising from factory defects are few and far between, but some still make it through the cracks. One such problem is the blisters that form on asphalt shingles. In today’s post, Earl W. Johnston Roofing takes a look at what causes blistering and what can be done if you find them on your roof.

What Are Asphalt Shingle Blisters?

Asphalt shingle blisters are small, bubble-like protrusions that appear on the roofing surface. Not to be mistaken with hailstone damage — which looks like blisters when seen from the ground — blisters can appear on shingles without warning. They are caused by excess moisture trapped with the asphalt in the backing material during manufacture. Shingles with this manufacturing defect will develop blisters as the excess moisture expands from exposure to heat from the sun.

The blisters usually become visible within a year after installation. Unfortunately, blistering cannot be prevented by tasks such as maintenance and roof cleaning, as it is a manufacturing defect. Insurance companies do not cover blisters either, because they generally consider it as a cosmetic issue. While they do not affect the roof’s performance, blisters are noticeable from the curb and can affect your home aesthetically.

What Should You Do if You Find Asphalt Shingle Blisters?

The good news is that most reputable manufacturers have limited warranties that include coverage for asphalt shingle blisters. Investing in well-known roofing brands by working with designated roofers can help reduce the chances of blisters forming in the first place. Roofing products from manufacturers such as GAF products undergo strict quality inspections before they are shipped to contractors.

In the event that you find blisters on your asphalt shingles, the first thing that you need to do is contact your roofing contractor. They will conduct a closer inspection to determine the extent of the blistering, then discuss with you how much work will need to be done. If only a few pieces are affected, then only those pieces will be replaced.

Earl W. Johnston Roofing is a GAF Master Elite® contractor serving Coral Springs and Weston, FL, and other communities in Broward County. To learn more about our roof repair and installation services, give us a call at (954) 989-7794, or fill out our contact form to schedule an appointment.