Hello,
I am sure this has been asked before but asked before. I bought a 1995 wilderness. The old owner showed me where it had leaked before, a little spot in the right front in a kitchen cabinet. He thought he had fixed it. I thought so too as it had rained several times and I never saw it, then there it was. Well long story short I done a pretty major patch in about a 2 foot square area. Then I proceeded to put two coats of sealer on the entire roof. I had not paid attention before, but I have noticed that there are little blister looking and feeling places throughout the roof. Maybe 25 to 30 total, anywhere from dime size to half dollar size. Depends on the weather condition, as when it is hot and sunny they are gone. My question is this anything to worry about.
Thanks,Ben  

First, is the roof material EPDM? (read rubber roof) If it is, putting a sealer on the EPDM is generally a no-no. Seems any kind of solvent will degrade the EPDM to failure. Since you are seeing blisters, I feel sure it is a polymer roof. I think I would get out the worry beads.

Depending on what the roof is made of and what you used to coat it with it could be a couple things.As merc said if you used a solvent based coating on the rubber roof you may have a problem.It also could just be areas where you didn't get the surface clean enough and it isn't adhearing to the old surface.

OK here goes with the best way I know how to explain it. I said I done a patch job on the corner to start with. Well there is a rubber material and over it is a very thin "layer". This outside layer is white. This outer layer is what is blistering up in some places. Like I said about the size of a dime to a half dollar. It almost looks like a heavy layer of paint is loose. I used HENG'S rubber roof coating to go over the roof. It says it is formulated from 100% acrylic latex polymer. It says it is specifically designed for elastometric roof mastics. Basically it looks like white paint. As far as the blisters go I didn't look at the roof to amount to anything before all this started so I don't know if they were there or not before I used this. Like I said it depends on if the sun is out and etc, sometimes they are there and sometimes they are not.

My 2008 Cedar Creek has a few of those also.It's just spots where they didn't squeeze out the air bubbles.I say monitor it and see if they get bigger then figure out what to do then.Mine have stayed the same for two years now and I have not noticed any new ones.Since you used the correct material I would bet they were there before you coated it.

Thanks, that was sort of what I thought, but being green I wanted to make sure. They had this roof put on so a few small blisters as long as they are water tight I didn't see a problem. Thanks for the answers.