Roll Roofing Cracked And Blisters

Alligatoring is a crazed cracking pattern in the roof s surfacing.

Roll roofing cracked and blisters.

Rolled roofing usually expands and contracts with temperature changes as the building settles and the roof ages. This means the roofing can be installed without a coating of hot tar applied first. Blistering and alligatoring are two problems that are common among membrane roofing systems. Roll roofing also known as composition asphalt roofing is designed for cold installation on roof sheathing.

How to tell the difference. It looks a lot like alligator skin which is where the name comes from. This area can fill up with air or water to form a blister which looks like a bubble on your roof. Blistering is a different phenomenon in which bubbles form underneath the roof s membrane.

As this happens the different layers become wavy or blisters can develop and crack open. A roof blister is a raised area where there is a loss of adhesion of the roof. If left untreated a blister can grow larger and allow more moisture to get in so that the problem gets worse until more extensive repairs and possible replacement. Over time the combined effects of weather and water can cause raised ridges or blisters in the roofing that are prone to cracks.

Hail damage compared with blister rash damage on asphalt roofing shingles.