Roof Leak

Dicor Self Leveling caulk on the roof.

Consider covering the seams with Eternabond.

If you have a walk-on roof, use the water hose, and also from the ground level in that area.

Do a pressurized cabin air leak test would be my suggestion. That may not be the only area where you have failed sealant and/or leaks.

Dicor self leveling lap sealant is a Forum favorite for sealing on EPDM roofs. Eternabond tape is extremely good, also.

Could it be a leaky hatch door?

tbred wrote:
Could it be a leaky hatch door?

The tissues with water stains are above the hatch door, so I think it's a leak that found it's way down. Those tissue boxes must have been perfectly located to absorb the interior water because I can't find any sign of interior damage. I'll have to add wood to the hatch because the weight of the hitch seems to be a problem there now.

Thanks for the caulking tips. No idea how to do an interior presssure check.

LynnandCarol wrote:
If you have a walk-on roof, use the water hose, and also from the ground level in that area.

Not technically a walk on. Your ground level comment makes me wonder if the leak could be on the vertical front seam instead of the roof.

Hello. If you enter Seal Tech 430R into your search engine you will find dealers in your area that use this machine to do pressurized leak tests.

I would do the pressure test. I would seal up all the clearance/marker lights too.

Seal Tech 430, two of them, about 2 hours away from my trailer. That's doable. Thanks for the idea to check the running lights for leaks, too.

LaunchnRetrieve wrote:
Trailer still appears to be in good condition, but there are signs of a water leak in front right corner of trailer.
No sign of water damage on wall, but front storage has depressed wood floor near hatch door and small pile of yellow "powder" sitting just inside hatch door on ledge. Inside two tissue boxes seem to have absorbed water with discolored tissues all stuck together.

OK, so I'm assuming a roof leak that hopefully just needs some caulking. Any advice on confirming that I have caulked the right place and that leak is just from aged caulking leak?

What kind of caulk should I use?

IMHO it is almost impossible to successfully caulk the four roof corners on a typical trailer. The area I'm talking about is shown in the pic below and the issue is the "pooling area" formed by the cap to roof ridges and the cap/side metal insert molding that typically runs up onto the roof for 8 or 10 inches.




The two issues are except for some of the marine caulks and Eternabond none of the other caulks are meant for submerged use and even the marine caulking like the 3M 4000/5000 series is only designed for a primary seal when used between two surfaces that are fastened together. Also, regardless of how the trailer is leveled at least one and usually two of these corners are going to have "POOLS" of water sitting in the above area for days at a time.

What I did and some don't like my approach since they think it makes the area ugly and obviously a prior problem because of how it looks. However, I took the approach that I didn't care as long as I felt I had really protected that area from potential leaks and if the next owner couldn't understand why I did what I did then that person really didn't understand the real issues involved anyway. When I redid and modified my corners I stared off by trying to feather/slope that are so water would more likely run off onto the roof and not "SIT" in that corner area. For this I first cut some triangles out of some thicker plastic/acrylic and put a triangle in each corner and then layered everything in strips of overlapping Eternabond and that included the entire metal insert molding and it's roof end front on the roof to where it turned to go down along the front/rear caps. Below is a couple of pics of two of the corners finished being "ENTOMBED" as I like to now call it.