Air Bubbles in EPDM Rubber Membrane 2

[bsrd]

Could anyone enlighten me with what may have caused this rubber membrane to get these air bubbles in it. The EPDM was used in an attempt to seal up a leak on a metal roof that had a galvalume finish. I am not sure what type of adhesive was was used to adhere it to the metal panel. Is the EPDM delaminating?

 

[Compositepro]

It is most likely just air that was trapped under the membrane during installation. The trapped air starts as a thin gap under the membrane, but the surface tension of the adhesive will cause the surface area of the bubble to minimize. The end result is a large round blister rather than a thin air gap under the membrane. Poke a hole in it to let the air out and then seal the hole with adhesive.
There are specific techniques required during installation to minimize the amount of air entrapment. If the membrane were transparent these techniques would be obvious.

 

[tom1953]

Another possibility is that there was some residual solvent in the adhesive (or some other volatile hydrocarbon) that has swollen the EPDM rubber.

Tom Jablonowski, TSE Industries, Inc.

http://www.tse-industries.com