Roof blisters are raised bumps on roofing shingles, panels and coatings. They are usually caused by heat from the sun. Roof blisters are problematic because they can lead to leaks and roof underlayment damages.
Typical Causes of Roof Blisters
Roof blisters happen and continue to evolve. These four faults are the typical causes:
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Poor Bitumen Mopping
One of the most common causes of roofing blisters is when a contractor uses bitumen mopping and fails to dry the area before applying a roofing membrane. Bitumen mopping uses a heated and liquid form of asphalt to seal cracks in a roof. Poor bitumen mopping can cause blisters because the asphalt seals in any moisture on the roof. -
Trapped Debris
Trapped debris in built-up roofing (BUR) can create a blister on the roofing surface as the object presses against the material for a long time. If the debris degrades the water and produces acids, it will cause massive blisters. -
Uneven Gasses
Roof leaks will cause uneven air pressure inside BUR layers, which causes blisters in turn. Roofers must properly remove moisture before sealing roofs to avoid this from happening. -
Bitumen Bubbling
Bitumen bubbling occurs when the bitumen, or tar sands, are heated. Under the right conditions, the bitumen can liquefy and contract, leading to blisters on the surface. These blisters are sometimes referred to as tar pustules.
All isn’t lost when your low-slope roof has blisters. Here are some solutions to fix and remove them.
Cold-Process Asphalt Roofing
Cold-process asphalt roofing is an installation process that heats materials as it forms and cools down. This process prevents the shingles from blistering or bubbling up and creating unsightly bubbles on the surface. It effectively dissipates moisture and gasses, which causes blisters in old materials.
Blister Removal and Felt Patching
Asphalt felt patching replaces and repairs roof surfaces with new materials to remove blisters. Felt can prevent water from seeping through the cracks and blisters in the asphalt. After installation, the patches are subsequently covered by a layer of flexible asphalt membrane, allowing it to cover the blisters in the process.
Remember that prevention is always better than fixes and repairs. Here are some steps to prevent blister issues in the future.
Install Within Manufacturer’s Specifications
Roofing installation specialists must pay attention to the roofing’s installation specifications. Missing crucial steps can trap moisture and gasses that can cause blisters.
Limit Foot Traffic
Footsteps cause premature asphalt degradation, making limited foot traffic improve its lifespan immediately.
Keep Your Roof Cleaned and Properly Maintained
Debris, twigs and fragments can get trapped on roofing services. Make sure to inspect each area, and remove them.
Perform the best BUR installations and replacements by contacting the best roofing team at Premier Systems Roofing. Give us a call at (605) 361-4955, or use this form to reach us and get a free quote now.
