repairing leaks around roof vents

[SMCrane1554]

Suggestions for best way to repair leaks around roof vents?

[rvcycleguy]

Best way would be to remove factory caulk material and replace with new. Even go so far as installing a flashing material. Water leaks, on any RV, and specifically on the TM can lead to internal damage that may not reveal itself for months, years.

Generally a surface applied product over top of the factory sealant is temporary. Especially those " as seen on TV " products. Takes time and patience to do the best job. The prep work taking it down to a clean surface is crucial to any new product adhering and sealing. Then, you may think or consider covering the TM in those critical vent areas when the camper is parked , stored in direct sun for long periods of time.

[mcollect]

What is the best sealant for the roof vents?

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Originally Posted by mcollect

What is the best sealant for the roof vents?

Check out Eternabond tape....I think it's pretty good stuff if put down correctly. So what do you say forumites....howza bout Eternabond tape?
Tom who like it...

[gonzo628]

EternaBond is SOLID, a wonderful functional solution, but not very aesthetically pleasing. Now, if it is to fix roof vents, I guess aesthetics are not of much concern (areas around roof vents are usually only seen by Paul Bunyan or the 50ft woman) when the camper is setup.

[CAG1976]

I just had to fix some leaks around two of my vents and above the front exterior light.

For the vents I used an RV silicone and some Dicor lap sealant NON leveling.

On one vent the original caulk was still pretty good, but it had slow leak in one corner. After looking at the corner, it appeared there was a one inch spot where the caulk was pulled away from the riser boards under the vent and where the corners of the riser boards meet. So I just cleaned out those areas and removed loose caulk and applied the Dicor over that area because it was such a small spot. I would have redone and removed everything but I didn't have the time.

And on the other vent I did remove EVERYTHING and took it back to the painted metal. This was the exhaust fan over the door. That one was leaking at the corners of the riser boards and under the riser boards. So I had no choice but to remove it completely. It was pain to get the old caulk residue completely removed. I ended up having to use a metal putty knife and razor blade to get the last of it off. I did add some scratches by doing this but I figured it was going to get covered over anyway. I also went ahead and replaced the riser boards with new PVC trim boards from home depot and I gorilla glued the corners together to hopefully prevent those corners from separating like they did before. They were just stapled together by the factory. I siliconed down the riser boards with double beads, and the fan flange too. I made sure to keep the silicone caulk from oozing outside too much because I used the Dicor non leveling lap sealant on the outside edges and corners. This repair has held up well because we just had 4 or 5 inches of rain last night and it did not leak. I don't know about the other two areas I caulked. I just did those this morning but its supposed to rain every day here for the next few days so we shall see. The worst leak I have had was from that outside light on the front shell above the tongue. Water tends to run down right on top of that light and it was letting water into the light fixture which was flowing back into the trailer right below the front shell cabinets above the front bed (3124kb).

[CAG1976]

And one comment about the Eternabond, I ordered a roll of that too. I thought I was going to use that stuff, but after some research and talking to others I decided against it for now. At least for the vents it seemed to me that there is a decent chance that at some point I may have to fix or replace one of those vent fixtures. And I think trying to remove the Eternabond tape with a heat gun sounded even worse than removing stubborn caulk. I am however considering using the tape on other joints where I should not ever have to be removing things such as along the sides of roof shell where roof meets the corner trim. Those areas are long and they seemed like a good place for the tape since I shouldn't be replacing anything along there. I have wondered though how the eternabond tape holds up when the front shell is sitting on the back shell going down the road. I was concerned about the shells rubbing on the eternabond tape while driving and causing other problems.

[Gwenne & Len]

Using house construction flashing approaches you would use a self attaching product like Ice & Water to flash over the curb - down the riser face and out across the roof an inch or so. To protect the Ice&Water from uv you would cover it with a z flashing of (white) aluminum flashing material sealed at the seams and around the perimeter of the intersection to the roof.
This or just the aluminum flashing applied squeezing a coating of sealant beneath it.
Are there drawbacks to either of these approaches? Our 05 uses un flashed wooden risers which seem contrary to quality construction practice.
Len

[chay1950]

Originally Posted by SMCrane1554

Suggestions for best way to repair leaks around roof vents?

The best way IMHO is to strip off all of the old caulk and start fresh. WD-40 works very well in loosening up silicone and making it much easier to remove. Use Butyl tape between the roof surface and wooden/aluminum riser frame and between that and the vent or the fan vent. Tighten it all down and then use Dicor 501LSW non-sag caulk to cover up the seams and everything else. I saturated the entire vent frame with caulk.
Now if you're a belt and suspender type like me, I then brushed on a coat of Geocel Proflex RV coating. This will seal up a submarine. It's like brushing cold honey and it really sticks to everything.

If the old caulk is still basically good and you don't want to go thru the hassle of stripping it all down, then using the Geocel Proflex will seal it up again.

I'm in the process of doing this now along with a window and the backside of the awning. So far so good.

P.S. All of the previous answers are good. It just depends on your skill level.

[chay1950]

I did a small test on some left over Cofair Peal & Stick Aluminum tape. This is equivalent to Eternabond. I got it free, so the price was hard to beat. The attached picture shows where I applied Geocel Proflex RV flexible sealant (caulk) on the left side of the picture. On the right side I applied the sealant, let it set up and then brushed on the Geocel Proflex RV multi-purpose brushable repair coating. Both adhered very well, did not peal off and proved to be very flexible. I could bend and twist my sample and there were no cracks nor pulling away from the aluminum. They both worked as advertised. This picture is best viewed with Microsoft Paint in order to read what is in the arrows.