Roof Leak Advice & Insight

We have a 1995 TM that has developed some significant leaks…significant in that they seem to be all over the place, not necessarily a huge volume of water coming in. After looking through all the “leak” threads here, I'm sure it's the trim that needs to be re-caulked, so I am planning on re-caulking all the corner seams on the exterior of the roof, as well as possibly the center trim piece although it does not seem to need it.

I’ve noticed that the trim on my roof differs from the trim on newer roofs (see my pictures), so I hope somebody that has or has had an older TM may be able to enlighten me to some degree on the construction of the roof and how the trim on my roof “works”…I don’t know if just removing the old caulk from the seam formed by the trim and the roof is sufficient or not. The aluminum trim piece on my roof edge has a center channel with a piece of “floating” vinyl type material that is either slid-in or is pushed inside it. I haven’t removed it, but at this point I am assuming the vinyl piece may cover some screws that hold the trim piece in place and possibly the roof to the side walls?? If that is the case, it seems like I could possibly be getting some leaks from inside the channel of the trim via the screw holes in addition to the seam between the trim piece and the roof where you can see the caulking. My roof does not have an interior aluminum angle brace like the newer models have (based on the interior pictures posted by commodor47 http://picasaweb.google.com/commodor47/RoofLeak#), and that is why I am assuming the outside trim piece is what holds the roof to the side walls. Hopefully somebody here knows for sure as I don’t want to have to start pulling stuff apart unless I absolutely have to, and then only if I have replacement parts on hand in the event something needs to be repaired/replaced.

We have a Camping World about thirty minutes away, so I went there yesterday and picked up some tubes of caulk…two types, one a self leveling and the other a non-leveling, for horizontal and vertical surfaces, respectively. They are both made by Dicor and were $8 a tube, which is twice the cost of the DAP Alex Ultra230 caulk I used on my house this spring when I painted it. I guess the Dicor caulk is superior in some way to the DAP caulk so much so that it justifies the cost? I don’t necessarily mind spending twice as much on caulk if that’s the case, but would like to know if anybody has had any issues with it versus, say, a run-of-the-mill but high quality caulk like DAP. It looks like the caulk used (by the factory I assume) on the horizontal surface is not a self leveling caulk, so I'm not sure if I really need to use this type of caulk. Any thoughts? There does not seem to be any caulk on the vertical surface where the corner roof trim meets the side wall of the TM so I plan on using the non-leveling type caulk there as (1) it couldn't hurt to have it there, and (2) it seems there is a potential for water/moisture to wick into this seam without it.

I've got about 9 months of tree litter and dirt to clean off of the top of my TM before I re-caulk, and was going to pressure wash it off, but on second thought that will probably just put a lot of water inside the walls given the leak problem, so I'm just going to have to do it the more labor intensive way with a bunch of elbow grease . I bought a plastic caulk removal tool to (hopefully) get most if not all of the old caulk off the trim/roof...any advice for getting the remaining scraps off?? Alcohol or acetone seems to be the popular recommendations. Any other advice or insight would be helpful...I want to get this done RIGHT the FIRST time so it won't have to be done again (hopefully) for a long time.

Tony

I've had good luck so far with G.E. Silicon II exterior home caulk. It's available at Lowes and other large hardware stores. Supposed to be pretty flexible over a long period. Seems to stick pretty well to both plastic and aluminum on our trailer. Not sure if it's any cheaper.

[MariaG]

We have a 1986, so considerably older. It has the same kind of trim, so it may be more similar to yours than a newer model - there are a lot of pictures of our rebuilding saga on my blog, the link is in my signature below. I _think_ we used white silicone caulk on everything, but I can't remember for sure.

Self leveling caulking is mostly used on trailers with membrane roofs to cover seams and screws where water can pool. As others have said, I would use a good exterior silicone preferably with a mildewcide.

Water always runs downhill. If you have leaks on two or more different points on the trailer investigate seams on the high points first and don't ignore the areas around vents and the air conditioner. We also had a leak once at our TV antenna.

[commodor47]

Tony,

Those are great photos and do indicate areas of possible water infiltration. That trim piece is similar to pieces found on my unit - specifically along the front shell leading roof edge, on all four corners of the main box and around the outside storage doors. The center strip is a vinyl material used in many RV models. It should be readily available from most RV dealers. The ends of the vinyl strip is folded under on itself and can be tricky to remove. Applying heat (maybe a hair dryer) should soften the vinyl and make undoing the folded end a bit easier. Your assumption of hidden screws is correct. I would suggest you concentrate on the replacing the old caulk first. If that stops the leak(s) there is probably no need to remove the vinyl strip(s). It might be a good idea to replace the caulk along the center of each shell roof and around any skylights.

Dick

Hey Ya'll,

Thanks for the replies...it's really a big help.

As soon as I get some clear weather, I'm gonna get started. I think I'll stick with the Dicor (I'll return the self-leveling stuff) caulk since I've already bought it and it's made specifically for RV use. I couldn't find any information (even on the Dicor website) as to what type of caulk it is (i.e. silicone, polyurethane, butyl, or some type of hybrid...it's definitely not acrylic or latex as it requires mineral spirits for clean-up), but in my searches on some other RV forums it seems to come recommended and works well.

Maria - I read your blog with interest and noticed that you were going to use a cut piece of 55-gallon drum as a wheel-well guard. Last Aug/Sept when we joined this group, I saw the plans for using sheet metal and had planned on doing that over the winter. Little did I know that I should have done it right away...a trip down to P'cola in Oct resulted in an unfortunate de-lamination of the tread on the driver side wheel which of course slashed a big hole in the forward part of that wheel well. The immediate damage was minimal, but on the way back home we ran into a few hours of rain, which was then slung by the wheel into the new hole inside the kitchen cabinet and then ran out onto the floor. We got home, opened the TM only to find the carpet soaked. I've since pulled up the carpet and pad and replaced it. We have spent the last few months renovating the interior with new upholstery among other things. Please let me know how the 55-gallon plastic worked as this will be my next project and I'm always open to different ideas. Seems like it might be a little easier to work with.

Dick - I will be sure to go ahead and do all of the skylights as well as the center roof...I saw somewhere a discussion about a tape product called Eternabond and think I may consider using that on the center "seams" of the roof.

Tony

[hhoenig]

I was plagued with stubborn roof leaks untill I came across "C-10 flow seal". It is a self leveling caulk sealant that solved my problems. My RV dealer sells it for $10.98. It worked so well, I used it in my shower at home. Worked great. Use it on the center seam and side seams. Good luck.

[MariaG]

Hi Tony -

Fingers crossed, we haven't had a blowout yet, so I'm not sure just how well the drum will hold up. However, it is very thick and my husband thinks it will do the job. I hope we never have to find out, but if it happens I'll definitely report it here!

"I bought a plastic caulk removal tool to (hopefully) get most if not all of the old caulk off the trim/roof...any advice for getting the remaining scraps off?? Alcohol or acetone seems to be the popular recommendations."

So I don't see anyone answering this question, which is what I'm trying to figure out right now. I just tried Lift-off and it takes the paint off (to be fair, it does say very clearly that it is not recommended for painted surfaces).

[mcgyver210]

We plan on re-caulking ours soon because it is showing signs of caulk releasing. I decided to use the GE Silicone II in the newer Gold Tube due to all the negatives I have read on caulk supposedly for Travel Trailers.

We don't have leaks yet but I am more proactive than reactive & I see the center strip lifting also.