Roof Blistering on Built-Up Roofing

Home Austin Roof Blistering on Built-Up Roofing

Work With the Best Roofing Contractors in Central Texas

Quality is at the heart of our Austin roofing company in every project we take on. Contact our experienced Central Texas roofers for a same-day, pressure-free inspection. Call 512-375-3654 to book your free inspection.

If you need a new roof installed, LOA is the roofing company to call! Our roofing experts are known for providing quality workmanship at a fair price. If you own a house or business in Central Texas you can’t afford to work with another roofer.

Find out how much roof replacement will cost in Austin, Texas and the surrounding areas.

Schedule a FREE Roof Inspection

Why a Roof Membrane Might Split or Tear and What to do if it Does

If you see raised up spots that look like bubbles on your built-up roof your eyes aren’t playing tricks on you. What you’re seeing is something called roof blistering. Some roof blisters are so small you can’t see them while others are large and can damage the protective surface of the roofing system.

Blistering on a built-up or mod bit roof is similar to asphalt shingle blisters in how they form. However, the chance of roof blisters can be even higher with built-up roofing because there are more layers of material, and it’s usually installed on a low slope and flat roofs that are more prone to moisture problems.

Need to fix roof blisters on a built-up roofing system?

Take the First Step – Contact LOA to Request a FREE Roof Inspection!

Types of Roof Blisters on Built-Up Roofs and Why They Happen

There’s one type of asphalt shingle blistering, but with a built-up roof you can have two types of blisters that can form.

Blistering in Between the Substrate and Membrane
Blistering between the membrane and bottom layer of the roofing system (substrate) happens when heat from the sun expands trapped moisture and/or air forming an air pocket. It’s a result of the substrate having low permeability, which doesn’t allow the heat to escape through the substrate. With no way to escape pressure builds and the blister grows. When this happens the membrane gets stretched. If it stretches too much the membrane won’t go back to its original state once things cool down and the air pocket is there to stay. When the temperature rises the cycle will start again, causing the blister to grow.
What Causes Blistering in Between the Substrate and Membrane
Roofs are going to take a beating from the sun no matter what material they’re made of, but some materials are more UV resistant than others. The materials used for a roof membrane are resistant, however over time the UV rays degrade them. With each passing day the UV damage builds and makes the membrane more prone to tearing.
Debris Collecting on the Roof Surface
When blistering is occurring that the lowest layer it’s related to the substrate. As noted above, the permeability of the substrate plays a role. Other contributing factors include uneven substrates and insulation that isn’t adhered fully to the substrate.
Blistering in Between the Membrane Plies
When a roof blister forms between the layers of a built-up roof it’s known as blistering between the membrane plies or inter-layer blistering. Trapped air, moisture or a combination of the two is the catalyst that will form blisters. When the heat rises the trapped air/moisture expands causing the blister to grow.
What Causes Blistering in Between the Membrane Plies
When inter-layer blistering happens it’s often a sign of installation issues, including:
- Skipping in the bitumen mopping
- Debris that was entrapped
- Felt that is curled
- Moisture in the roofing materials
- Not allowing enough drying time between layers
- Roofing layers that aren’t bonded well

Other Contributing Factors for Roof Blisters

Research has shown that improper installation and application alone isn’t the sole cause of most roof blisters. Even if everything is done correctly a blister can still form because no built-up roof system is 100% free of voids that can trap air and moisture.

Problems during installation may be the underlying cause but other contributing factors come into play that can increase the chance of a blister forming with or without installation issues.

Extreme Temperatures and Fluctuations
Areas where the temperature fluctuates from hot to cold tend to have more roof blistering problems. The expansion and contraction from the temperature changes can cause voids where air and moisture can get trapped. Temperature fluctuations also increase the amount of condensation that’s present and can get trapped to create a blister.
Poor Ventilation
Poor attic ventilation or ventilation between the layers of the roofing can cause moisture build up. When trapped air and moisture have nowhere to go a blister can grow.
Drainage Issues
If water isn’t draining off the roof it will pool and possibly seep below the surface. Drainage issues can stem from the entire slope of the roof being off, lack of a drainage system that directs water off the roof or debris build up in gutters.
Improper Maintenance
Regular maintenance helps correct and prevent many roofing issues, including the formation of blisters. Having the roof inspected regularly allows you to detect leaks that can allow moisture to get trapped below the surface. When you fail to take maintenance measures small leaks can turn into bigger issues.
Hail Damage
In areas like Texas where hail storms occur there’s a higher likelihood of roof blistering. Hail damage in the form of tiny tears can allow moisture accumulation in the lower layers.
Heavy Foot Traffic
Heavy foot traffic alone may not cause air or moisture to get trapped, but it can make problems worse and increase the presence of blisters when there are issues with the substrate.

Repairing Blister Damage on a Built-Up Roof

If you notice blisters it’s time to contact a roofer. A few small blisters on built-up or mod-bit roofing isn’t typically a serious concern because the roof membrane should be elastic enough to handle the limited movement. It might affect the roof’s appearance but not its performance. Even so, the problem should be inspected.

However, larger or more numerous blisters can cause roof damage and premature deterioration that harm the roof’s integrity and reduce the roof’s lifespan. Popped blisters can damage roof coatings and protective granules, allowing water to penetrate through. Roof blistering is also an indication that there could be other issues with the roof system that needs to be addressed, which is one more reason to have them repaired by a professional.

Repairing Unpopped Blisters on the Roof’s Surface

You may not be able to prevent blisters completely, but they can be repaired. If there’s unpopped shingle blistering that has impacted the roof’s surface you’ll need to reapply the protective coating in the affected area. It’s also important to monitor the blisters moving forward to ensure they aren’t getting larger.

Repairing Popped Blisters

If blisters pop you’ll have to make more extensive repairs so that water damage doesn’t occur. There are two ways to fix popped blisters:

You can remove the entire blister and area around it. Next, you’ll need to use layers of felt and asphalt to patch the removed portion.
The other option is to cut the blister open, pull the roofing back, fill the void with asphalt, press the roofing material back down and patch over it.

Fortunately, roof replacement isn’t typically needed if a blister pops. But there could be an underlying cause that needs further correction. For example, steps may need to be taken to ensure proper ventilation so fewer blisters form in the future.

LOA is a top-rated roofing company in Central Texas that knows how to handle roof blisters. If you aren’t sure whether blistering is a serious concern schedule a free roof inspection. It’s the easiest way to know what steps need to be taken to correct blistering. Contact our team today to schedule a free inspection.

We're One of the Highest Rated Roofers in Austin for a Reason

Thanks to Landon Wells of LOA Construction for the beautiful new roof! It was all completed in one day including a meticulous clean up job afterwards. The workers were all polite and professional. Landon made sure everything went smoothly and that all of our questions were answered. I am thrilled with our new roof. I would definitely recommend Landon and LOA Construction to all of my friends and family. Thank you Landon!

— Renee Johnson

★★★★★

"I got three inspections and decided to use LOA Construction for a new roof. LOA’s Dan Harvey worked with my insurance inspector to make sure all the hail/wind damage was accounted for, gave us a good choice of shingle colors, and was great at communicating. The workers did quality work, found and repaired rotted wood and cleaned up. Highly recommend!"

— Brian McFarlin, 5-Star Google Review

★★★★★

"Brandon at LOA construction made replacement of our roof very easy. He was the only roofing contractor that I could find that would work directly with our insurance company. They showed up on time and made the whole process very easy. And we have a great looking high quality roof! I Would definitely recommend them to anyone looking for a new roof. Give them a call if you need a roof or think you might have wind or hail damage. I had several other bids that were higher cost and didn't think our insurance would cover it. Our insurance did cover it, I think they were just unwilling to work with the insurance company. Not Brandon, not only was he will to work with our insurance he met with the adjuster and made the whole thing a breeze. Thanks again LOA and Brandon!!!!"

— Mike A., 5-Star Google Review

★★★★★

LOA Construction has exceeded my expectations again. This is the second roof installation with them and I couldn't be happier. Specifically, Tyler Griffiths is professional, attentive, and made the entire process of working with my insurance company effortless. My tenant sent a glowing account of their experience as well. Knowing it was a rental, they still diligently protected all property and plants. They were on time every time and went out of their way to not inconvenience the residents. LOA Construction has integrity and takes pride in their work. I couldn't recommend them more.

— Sheri Moran

★★★★★

"Worked with Zac and his team. Zac did an outstanding job working with the insurance company to ensure all damage was covered. Roof and gutters installed each were on time and all work was top of the line. This is a company that really does put the customer first. With out question I would recommend loa construction and roofing."

— Tony Smith, 5-Star Google Review

★★★★★

From the very start, I knew I was in good hands. The professionalism was top-notch, but most important, was the caring attitude of the project manager, Dan Harvey, the roofing supervisor, Ambrocio, and the roofing crew. They made sure every detail was covered. They are definitely an asset to LOA Construction. I highly recommend them. Dennis and Suzy S

— Dennis Sanger

★★★★★

Andrew was very great at getting myself and my wife all the information and getting us started from start to completion. His workers were friendly and professional. If ever I had to contact him, he was quick to respond back. We are very happy with the finished product. Yes, I would and have recommended him and his company to get their work by LOA Construction and Austin. Andrew made sure my wife would be satisfied with whatever roof she liked. Can't thank you enough Andrew and LOA Construction.

— Paul Coleman

★★★★★

As a first time home owner with no experience in how to make claims and start the process of getting a new roof I was scared to the point of avoiding what needed to get done after the bad hail storm. August Walker did an amazing job walking me through each step along the way. He answered all my questions and calmed my concerns. They inspected my roof and drove from Austin to Belton just to be there with the ins inspector, and followed up with me in person after the roof was installed. He also made a special trip back to drop off samples! I’m grateful to August and LOA construction for being highly professional and friendly!

— Angela Baker

★★★★★

From start to finish Lee and his team took great care of us. He made us feel comfortable during the process and answered any and all questions we had. I would definitely them recommend to anyone.

— Taneisha Jones

★★★★★

Arthur Harris and his team with LOA Construction did an excellent job on our roof. They finished it in one day. Arthur was very good in explaining all the information to us.

— Crystal Hill

★★★★★

Will, has been so awesome and easy to work with he gets everything we want done the way we want it and also keeps us updated as we are over the road truck drivers !!! Hands down to LOA Construction for their great service and great customer service !!!

— Tanya Dudkiewicz

★★★★★

Dan Harvey is Very Knowledgeable and directed me straight to the products that will save us money in the next 3 years the savings on energy costs alone will pay for the installation itself. I highly recommend LOA Construction and Dan Harvey! Actual Customer Jefferson Fara

— Jefferson Fara

★★★★★

Mark from LOA roofing was very professional from the git, the initial estimate process, he quickly identified all the issues that needed to be addressed. The company was very prompt, to coordinate the crew, and for a very reasonable price, got my roof repaired without any hassle. They also took care of all the cleaning, so that it all looked like nothing happened. I would recommend Mark from LOA to anyone needing a roof repair, with no kind of hesitation.

— Ale León

★★★★★

Loa Construction provides quality services in installing roof and related repairs. I’ll recommend it to my friends and family.

— Peijie Li

★★★★★

Choose quality roofing for a lasting investment in your home.

Request an Inspection

Dedicated to excellence, our Austin roofing company ensures quality in every project. Contact our skilled Central Texas roofers for a same-day, hassle-free inspection. Call +1 (512) 375-3654 to book your free inspection.