Please help save my roof repair... and my sanity

[cumak]

I discovered this summer that my 10 year old Starcraft Travelstar had some pretty bad water damage in the roof. The damage was confined to the last 2-3 feet of the roof (probably coming from the skylight), everything else looked pretty good for it's age. So I decided to replace just the last 4 feet of the roof.

I cut away the EPDM and underlayment, and replaced it with a new sheet of 1/4" plywood and new EPDM. The old EPDM was laminated well along the edge where I scored it, and I scored the new EPDM so that it butted up almost perfectly. After everything was glued down I covered the seam with 4" Eternabond tape. So far so good, and the hard part was done...

Yesterday I was preparing to put it away for the winter and I decided to seal along the edges of that Eternabond tape I had put down. I figured another layer of water protection wasn't a bad thing. I put it down kind of thick and narrow, so afterwards I used a putty knife to gently spread it.

Today I went out and discovered that along the edges of the Eternabond, where I applied the Dicor, the roof has a bunch of bubbles. The bubbles are all in the area where I applied the Dicor, but they are actually under the EPDM. In other words, the Dicor adhered well to the EPDM, but for some reason the EPDM seems to have separated from the underlayment.

Does anyone have any idea why this happened? Did the Dicor grab the EPDM, and cause it to separate from the underlayment as it was curing? Did moisture somehow get under there? (It hasn't rained lately.)

More importantly, how should I repair it?

Is it still water-tight, despite the bubbles? If so, can I leave it alone? I only want to get maybe 4 or 5 more years out of the trailer anyway.

Or, is the moisture barrier comprimised? In that case, do I have to peel back the EPDM in that area and repair? I *really* hope I don't have to do that. This has been a pretty frustrating project so far.

Photos below. It's hard to see the bubbles in the close-ups, but hopefully you get the idea.

Thank you in advance for your help.

-Mark

[Huntindog]

That is COLD. It was around 60 when I did mine.. Cold for Phoenix. I guess I'd never had the issue before as it is most always a lot hotter here.

If you do an archive search (over 1 year old) you will find a lot of discussion about this... But everyone agrees that it is not a problem.

I did mine on friday. On Sat. I saw the bubbles. They had shrunk about 50% as of yesterday.. But from what I have read, the colder it is, the longer it will take for the Dicor to cure. Some say up to 30 days... So don't panic for awhile anyways.

[cumak]

Thanks everyone for your comments. This makes me feel a bit better. I'm confident that the adhesive under the EPDM was done correcty, and the Eternabond as well, so I'm just going to keep my fingers crossed for now and see how it looks in the spring.

Huntindog - maybe it's just wishful thinking but your explanation is in line with what I'm seeing. The temperature was in the upper 40's when I applied it, but dropped to the mid 30's at night. Also, the bubbles only exist on the "outer edge" of the seal, where the Dicor comes into direct contact with the EPDM. On the "inner edge", where the Dicor is in contact with the Eternabond, it's nice and flat. If your explanation is correct, then perhaps the Eternabond prevents that part of the membrane from absorbing spirits so bubbles don't form there.

Thanks,
Mark

[Huntindog]

I just replaced my skylight, and the Dicor caused the roof to bubble up... Strange as I have used it many times in the past without this happening.

I did a search here and found several posts about this. It seems that if you put Dicor on when it is cold out, that the sealant doesn't cure fast enough to keep the roof from absorbing some of the spirits in the Dicor... But that it is no cause for concern as they will disapate over time and the roof will lay back down... Mine is already looking better.

[westend]

Let it sit, the bubbles will probably go away. More than likely, you have three different materials with different expansion characteristics, causing the membrane to pull slightly. If you put down adequate adhesive under the membrane, don't sweat it.

[icanon]

I don't know the answer and I'm sure someone will have an answer but was the surface clean prior putting the Eternabond tape? I would try re-rolling the Eternabond tape again and see what happens the next day. Other than that I have no idea and probably start over which is a bummer!

DutchmenSport just answered before I finished posting, He's quick :B

[DutchmenSport]

It looks like it might be a simple case of moisture under the sealants trying to escape. The sun pounding down on the roof is heating the glues and sealers under. Simple evaporation to dry the glues is attempting to occur. With no where for the gasses to escape, they are forming bubbles. I don't think you have anything to worry about.

My Springdale did this all the time, the bubbles came and went, for about 5 years when it finally quit.

But, just to be certain, check it often for leaks. I think you're OK.