Overview

Ragsdale Roofing And Innovations LLC takes plenty of calls from homeowners describing raised bumps, bubbles, or pockmarks on their shingle roofs, but there are still many who don’t notice the issue until conditions worsen. This blog post is for anyone looking to understand what asphalt shingle blistering is, why it happens, what it looks like, and how to prevent it from turning into more expensive repairs.

Highlights

• Why shingle blistering is a concern
• What blistering means for your roof
• Repairing blisters

Introduction

Next time you step outside, turn around and glance up at your asphalt roof. Is the color uniform and tightly textured, or are there scattered spots that look sunken or raised? Those small irregularities might seem harmless, but they often signal what professionals would call early-stage blistering.

It’s an issue that slowly eats away at the material, but knowing what to watch for gives you an advantage. Add a little bit of good timing, and you can act before new vulnerabilities appear.

Why Is Shingle Blistering Concerning?

Shingle blistering might look like a cosmetic concern, and it is, but it can be much more. The raised bubbles can eventually pop, tearing away the granules that protect your roof from sunlight and weather. Once those granules are gone, the asphalt beneath is left exposed and begins to break down quickly.

Blistered shingles also don’t age evenly. Weakened sections can deteriorate quickly, making your roof more vulnerable in areas you can’t always see. The unevenness of wear can lead to patchy insulation, heat pockets, and an increased risk of leaks during heavy rain or storm season.

Moisture intrusion is the long-term threat. If blistering gets neglected (as it often is) and leads to water seepage, the damage doesn’t stop at just the shingles. It can spread to the underlayment, decking, and even the structural frame in some extreme cases.

How Long Does It Take Roof Blistering To Progress?

Roof blistering often develops slowly, with some shingles showing no change for months or even years. Once a blister pops, though, the exposed surface can deteriorate quickly. That’s why it’s better to simply call when you notice any concerning changes, even if something feels like it can wait.

What Does Asphalt Shingle Blistering Say About Your Roof?

There are a few key inferences that you can make about your roof if you have asphalt shingle blistering. Of course, before you draw any conclusions, you’ll need a professional inspection, but still, the information you can potentially gain will keep your system healthier both now and in the future.

One of them is that you likely have other issues beyond just blistering. The visible damage can be a symptom of a larger condition affecting your roof’s performance, which means a closer evaluation could uncover problems that are still in their early stages.

Another clue is that your roof might not hold up well under future strain. Blistering can mean reduced resilience, making the surface more vulnerable to temperature swings and physical impact that would otherwise pose less of an immediate threat.

The causes themselves also say a lot about how your roof is functioning, and what it might need before damage sets in, so the next step is understanding where the problem starts.

Trapped Moisture in Asphalt Shingles

Trapped moisture inside the shingles is often a manufacturing flaw. If the asphalt mix contains even trace amounts of water, or if the shingles are stored in damp conditions before installation, that moisture gets sealed in during production. Once the roof heats up under the sun, the water inside begins to vaporize, pushing upward and forming blisters just beneath the granule surface.

Since this issue starts from within the material, it can’t be repaired in place. Shingles affected this way usually need to be replaced outright. If the problem is widespread, it may also point to a bad production batch, which could mean your roof needs a broader inspection before any isolated repairs are made.

Lack of Proper Roof Ventilation

Poor roof ventilation can do more damage than just blistering. But still, it’s one of the primary symptoms. When this happens, the trapped heat radiates upwards into the roof deck and shingles. The elevated temperatures soften the asphalt layer, making it more prone to bubbling under surface stress. When it’s warm, the effect is even more pronounced, as both heat and moisture work synergistically.

Unlike manufacturing issues, this isn’t limited to a few shingles. It reflects a system-wide imbalance. Fixing the blistering alone won’t be enough if the ventilation problem remains.

Improper Shingle Installation

Improper shingle installation creates the conditions for blistering by leaving gaps in adhesion or creating uneven pressure points across the surface. If the shingles are nailed too high, not aligned correctly, or installed over debris, small voids can form underneath. These gaps disrupt the bond between the shingle layers, making it easier for heat and moisture to concentrate in one spot until a blister forms.

When blistering stems from installation errors, sections may need to be removed and reinstalled to restore a uniform, secure surface. Correcting the workmanship is essential. Otherwise, new shingles can end up with the same problem.

Low-Quality Roofing Materials

Using low-quality materials for any part of a roof is a gamble that never pays off. In shingles, cheaper manufacturing often means weaker asphalt, inconsistent granule coverage, and adhesives that fail sooner than they should. There are a few key ways to ensure you’re getting the very best, and it starts with choosing the right roofer and asking directly what brands and product lines they use.

When blistering is tied to poor-quality shingles, repairs become a question of long-term value. Swapping out individual pieces may buy time, but the same weaknesses will remain in the rest of the roof. Upgrading to higher-grade materials is often the only way to ensure lasting protection.

UV Damage to Roof Shingles

UV damage to roof shingles happens gradually, even though modern shingles are designed with protective granules to block much of the sun’s radiation. Those granules can loosen or wear away under constant exposure, leaving patches of asphalt exposed. Once that layer is unprotected, the sun begins to dry it out, making the surface brittle and more prone to blistering under heat stress.

The best roofers rightly understand that in this case, the roof is probably aging and losing its built-in defenses. While repairs can replace the worst sections, preventing further harm means addressing the loss of granules and protecting what remains, often through timely maintenance or, in some cases, a partial or full replacement.

High-Pressure Roof Cleaning

Cleaning your gutters and roof is an important part of keeping the entire system healthy. The problem comes when the job is done with high-pressure washing. The force of the water can strip away the protective granules on shingles, leaving the asphalt layer bare and more likely to blister under heat.

When blistering is caused by aggressive cleaning methods, repairs are only part of the solution. Protecting the roof moving forward means switching to gentler cleaning techniques that remove debris without damaging the shingles, so maintenance improves the roof instead of wearing it down. You can always ask your roofer which cleaning methods they recommend or can do.

What Roof Repairs Are Most Common for Blistering?

When blistering is caught early, repairs often follow a straightforward path. Mild cases that haven’t led to popped blisters or significant granule loss are generally not a serious threat. In these situations, the goal is to monitor the area, prevent further stress on the shingles, and address the underlying conditions.

The most common fix is to replace only the shingles that are visibly compromised. This approach works because it’s characteristic of blistering to affect only isolated sections. It doesn’t “spread” the same way a leak does. In the right situation, it’s cost-effective, minimally disruptive, and helps extend the roof’s overall life.

Still, the repairs you’ll need will depend on these factors, weighed during an inspection:

• How far the blistering has progressed
• Whether the blisters have popped and exposed asphalt
• The overall age and condition of the roof
• If the problem is localized or spread across multiple areas
• The type and quality of shingles currently installed
• Any underlying issues contributing to the damage

Is a Roof Replacement Necessary if Blistering Is Widespread?

A roof replacement might be the outcome you hope to avoid, but widespread blistering can sometimes make it the only practical choice. Understanding the causes shows why, when the issue is rooted in the shingles themselves or affects large sections, and if the damage may be too extensive for repairs to work.

It’s not the most common solution, but it becomes more likely when blistering is paired with other signs of decline. Roofers will weigh the scale of the damage, how much protective surface has been lost, and whether the existing shingles can still perform as intended. If the answer is no, replacing the roof can be the most reliable way to restore full protection.

Get Expert Help for Asphalt Shingle Damage

Blistering that stays contained may not demand immediate action, but when it accompanies curling edges or loose shingles, it’s even more urgent. Ragsdale Roofing And Innovations LLC has the skill and tools to address asphalt shingle damage before you end up spending more on preventable repairs or facing replacement.

Restore your roof’s protection before the next storm hits. Call (912) 346-8250 today!