How long should caulking hold up before redoing it?

[imq707s]

I've had our 2011 Crossroads Zinger for close to three year now. When I first got it I went through everything and cleaned out the old caulking on all of the joints, and redid it. Then last summer I noticed that some of that caulking had started to crack and look pretty bad so I redid a bunch of it again.

And now this summer/fall I've started to notice that once again, I can see several spots were the caulking around things has started to pull away and/or crack...and needs to be redone.

I've always used the high quality (and expensive) RV caulk, and it just doesn't seem to last very long.

Is that pretty normal, or am I doing it wrong??

[imq707s]

I thought silicon caulk on a camper/trailer was a big no no?

[GrandpaKip]

I use Lexel on everything but the roof. I do the best I can to remove every bit of the old silicone before recaulking. If the new caulk is pulling away, that is probably due to a film of silicone that has remained. It’s pretty easy to remove the silicone bead, but that film isn’t.
I’ve used a combo of GooGone caulk remover and a razor blade to remove the film. Still a PITA, but much of nothing will stick to that film.

[falconbrother]

I think for caulking on the trim and sides it's best to keep an eye on it and cut out and replace when it's separating around the edges. The roof is another issue. I wash mine two times a year. It doesn't take long. I inspect it really close and would use the proper sealants when needed. Back in the day our old 1991 Prowler had a metal roof. That was so easy to maintain.. These rubber roofs can have a leak so small you have a hard time finding it and it can hurt your feelings. Leak prevention is high priority stuff in my book.

[Bunklash]

Another vote for Eternabond here. I've even heard of folks stop using caulk on their roof in favor of Eternabond at all seams. But even it has it's limits. It was used from the factory on the seam between the roof and the end caps. Not knowing what I was doing, I caulked a few small cracks in the tape. Well of course new cracks formed. I ended up removing all the original Eternabond and Dicor and replaced all with new. It's holding up really well after two years.
As for the horizontal Dicor, I too had disappointing results. It shrunk and separated after about three years and allowed more water intrusion along the forward side seams of the fiberglass.

In the end, I highly recommend frequent inspections of all seams, roof and sides. Especially if your rig is wooden framed walls. Mine is aluminum studs, and so far the only damage has been surface rusting of the front frame pieces.

Safe travels, y'all

P.S. Never put Eternabond or any other sealant on top of new caulk. The caulk gives off gases as it cures and will form bubbles under the tape. OK to caulk over tape, but be aware if the tape is cracking, it will continue to deteriorate. Best to remove and replace.

[imq707s]

I think that all of the movement and vibration from pulling your trailer down the road is what causes a lot of the cracking/pulling away issues with the caulking. Your house is pretty stable....nothing like a trailer.

[Hannibal]

Would be really nice if Dicor would offer their lap sealants in smaller squeeze tubes for touch ups. I don't always need an open caulking tube with the caulk gun. Is there any caulk at Home Depot that would work on our RV roofs? We had new windows installed in the house almost 15 years ago and the caulk around the windows is still in great shape.

[allen8106]

Depends on the type of caulking used. I have had my rig since new in early 2011 and have only had to touch up a few placed where the caulking has shrunk away from screw heads and such. I use Dicor self-leveling for horizontal surfaces and Dicor non-leveling for vertical surfaces.

Works pretty well so far.

[Community Alumni]

On the roof I've switched over to Eternabond tape wherever I could. Do it right the first time and don't worry about it again.

[imq707s]

donn0128 wrote:
Dicor markets two versions. One for verticle and another for horizontal surfaces. I have tried ProFlex and it did not work for me. Redid with Dicor and it worked fine.

That's strange. I used the Dicor for horizontal (no sag) and it didn't last nearly bas long as the Proflex. Maybe I got some bad Dicor?

I did notice that the Dicor seemed to really pick up dust/dirt/mold badly...and turns dark after a year or so where the Proflex seems to still be white.

[donn0128]

Dicor markets two versions. One for verticle and another for horizontal surfaces. I have tried ProFlex and it did not work for me. Redid with Dicor and it worked fine.

[2oldman]

imq707s wrote:
I'm looking for a better lap joint/non sag type of sealant.

Ok.

[imq707s]

2oldman wrote:

imq707s wrote:
Is there something else I should try out?

Yes. Heng's rubber roof coating. Goes on like paint, seals everything. It was the only product that stopped my leaky skylight.

I never remove old caulk.. just coat it with that stuff. Much easier and works like a charm.

I'm having issues with the sealant on the side and horizontal joints......the self leveling Dicor roof sealent works great for the roof.

I'm looking for a better lap joint/non sag type of sealant.

[joelc]

Here is what I do First be sre you are NOT using silicone. I inspect my seams and roof twice a year. Any areas that are compromised the old sealant is removed and the area cleaned with alcohol. I use Dicor and Lexel. One is for the roof and the other is for the side seams. I meant to add. If you have any areas that are punctured use Eternabond roof repair tape. I had an area just to the rear of the front cap that got a branch in it. I covered it and the entire front seam with the repair tape.

[2oldman]

imq707s wrote:
Is there something else I should try out?

Yes. Heng's rubber roof coating. Goes on like paint, seals everything. It was the only product that stopped my leaky skylight.

I never remove old caulk.. just coat it with that stuff. Much easier and works like a charm.

[imq707s]

Any suggestions on what lap joint type calking works best. I've used Dicor, Silkaflex, and ProFlexRV....Proflex is by far the best, and holds up longer than the others.

Is there something else I should try out?