Asphalt shingles are still the undefeated leader for American households. They are affordable, they look great, and they’re effective and energy-efficient for a long time. If an American home is getting a new roofing system, chances are it’s asphalt shingles.

Asphalt shingles, however, are like other roofing materials that have certain weaknesses. One of the most common asphalt shingle problems is blistering. Blistering is an asphalt shingle roofing problem that is often mistaken for hail damage, and is one of the most common issues residential roofing contractors are called to fix, especially during the summer.

St. Charles Roofing Contractor takes a look at what causes asphalt shingles to blister and what can be done to prevent it.

What Causes Asphalt Shingles to Blister?

Asphalt shingle blisters can affect roofs of any age. Though blistering is more common in older roofs, it’s been known to happen to roofs that have recently been installed.

Shingles blister due to two main reasons:

The roof lacks ventilation: Heat is trapped in the attic if the roof doesn’t have enough ventilation. When this happens, the shingles get baked, leading to problems like blistering. Blister formation can be accelerated by poor attic ventilation. Trapped heat in the attic can raise the roof temperature to the point where it can form more blisters. Other areas such as the eaves, as well as siding that’s adjacent to the attic, can also be affected by the trapped heat.

The shingles have trapped moisture: Installed shingles are not supposed to harbor moisture. This usually happens before, when the shingles are being manufactured. If there is moisture in the environment, and it gets trapped in the shingles, once the shingles are installed and exposed to heat, the moisture expands. This can lead to blistering.

Preventing Blistering Shingles

Even if your shingles are new and do not exhibit any problems, it’s best to talk to your contractor about your attic ventilation. They can do something to correct poor ventilation. 

If you notice shingle blisters, remember not to let anyone walk on your roof as this can pop the blisters. As long as they don’t pop, your roof will be fine. Don’t let overhanging tree branches scratch or fall on the roof; call someone to trim the trees that are too close to the house.

There isn’t anything you can do if a hailstorm hits your area. Hail is more than likely to pop shingle blisters. This is when you need a professional contractor to replace your shingles.

To extend the life of your shingles, it’s best to remember these:

Don’t Go Cheap

Always buy top-quality shingles from known manufacturers and have a licensed professional do your roof installation. They will provide you with warranties for workmanship and material.

Have Your Roof Inspected Regularly

Regular inspections can prevent problems from developing or getting worse. If the inspector informs you of blistering, you have an opportunity to nip the problem in the bud by having affected shingles replaced. An inspection can also determine whether your attic is getting enough ventilation.