What is Thermal Blistering and What causes it?

Don’t Let Thermal Blistering Ruin Your Roof!

Thermal Blistering Example

Thermal blistering, also known as heat blistering, is a phenomenon that can occur on the surface of roofing materials, particularly asphalt shingles. It happens when heat gets trapped beneath the shingle, causing the air or moisture vapor to expand and create bubbles or blisters on the surface.

There are a few reasons why thermal blistering can occur:

1. Poor Ventilation: Inadequate ventilation in the attic or roof space can contribute to heat buildup. When hot air becomes trapped, it increases the temperature of the roofing materials, leading to blister formation.

2. Improper Installation: Incorrect installation practices, such as improper nailing or insufficient sealing, can hinder the proper flow of air and contribute to heat retention. This can result in localized areas of elevated temperatures and blister formation.

3. Dark-Colored Shingles: Dark-colored roofing materials, such as black or dark brown, tend to absorb more heat from the sun. The excessive heat absorption can increase the temperature of the shingles and make them more susceptible to blistering.

4. Extreme Temperatures: Rapid and significant temperature fluctuations, such as exposure to intense heat followed by rapid cooling, can cause thermal stress on the shingles. This thermal stress can lead to blister formation.

Thermal blistering can compromise the integrity and aesthetics of the roof. The blisters can trap moisture, leading to further damage if left unaddressed. To prevent and mitigate thermal blistering, proper roof ventilation, correct installation techniques, and using shingles with reflective or lighter colors can help reduce heat buildup and minimize the risk of blister formation.

If you suspect thermal blistering on your roof, it’s recommended to consult with a professional roofing contractor, like The Shingle Master. We can assess the situation, identify the underlying causes, and recommend appropriate solutions to address the issue and protect your roof from further damage.