Roof Coating Blisters

They are usually formed by the pressure of moisture beneath the surface of from lack of adhesion causing dry spots.

Roof coating blisters.

Blisters may occur below or between ply sheets in a built up roof system at the roof coating interface with the roof surface or between coating layers when multiple coats have been applied to the roof. When the roof heats up due to the sun or internal building heat this moisture evaporates and becomes water vapor that expands by up to 1300x its volume. Most blisters are caused by the same thing moisture. Once broken water is more likely to get under the coating or leak into the roof.

Loss of gravel granules or another surfacing membrane deterioration blisters in seams which have reduced lap coverage blisters that have breaks that can. Generally speaking unless its at a scupper or in a ponding area one broken blister is not an emergency. All conventional low slope roof systems experience blisters in some form. Membrane systems are most susceptible to blistering because blisters are formed by voids between the plies or at the point between the substrate and the membrane.

It is important to recognize the difference before proceeding. It is now trapped underneath the coating with nowhere to go. Bubbles across your foam roof will look like small or large rounded domes that stick up from the surface. Blisters may be filled with water or air.

Blisters are pockets in the roofing material with a spongy feel. This roof has way more blisters on it than normal.