Roof Vent Leak

Randy · 04-24-2014, 02:40 PM

I own a 2002 2720SL that has a persistent leak around the roof vent located in front of the air conditioner. The leak becomes apparent only after extended rains and appears to migrate from the space between the roof vent and air conditioner. Two years ago I removed all old calking from around the air conditioner shroud, the roof vent, and the roof seam front to back. I replaced all calking with 3M 4000 sealant and laid 6 inch rubber roof repair tap around the vent lapping it up over the screws, the valley between the air conditioner and vet lapping the tape up the front of the air conditioner shroud, and along the entire roof seam front to back. Despite this I still have a leak and the wood sandwiched in the roof around the vent opening is showing signs of deterioration. The hold down clips for the roof vent are tight, the hold down bolts for the air conditioner are tight. After reading the many similar treads on this topic, I am seriously contemplating pulling the roof vent and replacing it with a new one. Before I tackle such a project I would welcome any additional thoughts or ideas that may be out there. This is really frustrating.

Randy

Redtail Cruiser · 04-24-2014, 03:55 PM

So, if I understand your problem correctly the water comes in from the vent even though you re-caulked around it, the entire AC shroud and the roof seam. Did the 6 inch tape lap up around the entire shroud or just on the front side of it? If not maybe the water is getting in that way. How long does it have to rain, before you see water intrusion?

I hate leaks and they are frustrating to track down.

Randy · 04-24-2014, 09:03 PM

Hi,

It usually has to rain steadily for a day before water starts dripping our of the vent inside. I have not tape along the sides of the AC although I have re-caulked completely around the AC. Maybe that is a possible try. We love our TM but have been battling roof leaks for the ten years we have owned it.

Randy

Redtail Cruiser · 04-24-2014, 10:55 PM

Hey Randy, have you ever considered having an estimate done for an elastomeric seal coat. They offer a warranty for varying lengths of time, depending on the cost of job. Might be worth a look/see since you it sounds like your fighting a losing battle; however there are only so many places that water can enter. So, if one would tape and caulk every possible intrusion point on the entire roof, that "could" fix it, if not then maybe you'll need professional help.

Good luck, keep us posted, I'd like to hear how you get it resolved.

**dr carver** · 04-25-2014, 06:57 AM

I have heard of one service center finding leaks by pressuring he camper via a vent and using soapy water to detect leaks. You may be able to adapt something like that to our TMs.

Maybe a shop vac with the exhaust duct taped to a piece of plywood duct taped to one of the roof vents (open of course). Some tape to seal some of the gaps between the upper and lower shells. Fire up the shop vac, douse suspect areas with soapy water, and watch for bubbles.

I've never tried this on a camper, but it is the same basic operation as gas line leak checks, air line leak checks, reactor leak checks, distilling leak checks, and so forth. It should work well. It may be a lot of trouble to seal the camper, but not as much as blindly taking stuff apart and putting it back together!

tentcamper · 04-25-2014, 09:55 AM

There is so much going on in that location. The AC, roof vent, and the top roof epoxy roof seam. I assume you have replaced AC / roof seal gasket?

Do you store it out side? If so I would try taping off a garbage bag around the AC unit to the base for the AC, and check it after a hard rain. I have also heard of people using a garden hose to try to isolate a leak.

On an old camper I had. It took awhile to find the leak. It was a rivet in the roof vent cover. But looking at my TM, if the rivet leaked it would not leak inside. One of my campers when it rained hard or driven in the rain it would splash up and leak in a spot that the foam seal was missing between the cover and base of the vent.

What a PIA leaks are?

Randy · 04-25-2014, 12:46 PM

Hi,

Thank you for the ideas - they are all very helpful in thinking through this persistent problem. I have not pulled the AC unit although it has always been dry around the roof penetration so I haven't focused too much on that area. Elastomeric seal coating - i will have to look into it.

Again,

Thank you all,

Randy

Randy · 04-25-2014, 12:49 PM

Just a thought - has anyone had a rubber roof membrane installed on their trailmanor to combat leaks?

Randy

04-27-2014, 10:12 PM

I had a persistent leak in my roof too. Got it for a steal because previous owners couldn't fix it. The entry point of water was the front corner. The water traveled through the roof and out my vent... recaulked and leak gone! There's no telling where those things show up.

daveinfl · 10-10-2014, 01:07 PM

I know this post is from April, but now that we are going into the Fall and Winter months many people will begin working on their Trailmanor for next year. I had the very same problem as Randy. I spent well over $100.00 on the "wondertape" and it still did not solve the problem. I ended up cutting the tape off the corners of all the vents and just sealing them with with what seemed like a ton of the 3M 4000 sealant. It isn't pretty, but it did the job and stopped the leak.

I have decided my next project will be to cover the entire roof with Dicor Elastomeric RV Roof Coating. I have read on other sites that many people have used it with great success. I also ran into a TM owner not long ago that said he used it and never had a leak. I am going to lightly sand the room, trim down the 3M 4000 caulk and paint it on the entire roof and up and over the shrouds for the A/C and vents. My thought is that the elastomeric coating will fill in the small cracks. I have also heard it is best to do two coats.

If anyone has done this already, I'd like to hear your results.