Travel Star Roof Leak

I have worked on the roofs of two travel trailers. One a complete replacement and the other rebuild a water damaged corner along with walls too. In a wood frame trailer the roofs are basically like this. Sheet rubber, plywood or OSB deck, wood joist/truss, insulation, ceiling sheathing. I checked StarCraft web site and there roofs are just like that. When the trailers are built, the walls are installed on the floor deck, then the roof assembly is installed on top of the walls. So what happens is that ceiling sheathing is sandwiched between roof assembly and top of wall. So if you need to replace any of the ceiling system a special procedure is required.
If you only have a leak at skylight, I would assume that caulking at skylight is bad. If it was my trailer I would remove skylight from top along with trim inside. Lift up on rubber membrane a bit to see if wood deck is ruined. You can also push back insulation around opening and see if wood ceiling or truss is damaged. If they appear to be sound, then it is just a matter of reinstalling skylight with new putty tape and Dicore sealant around skylight.
If truss, roof deck or ceiling is bad, then you have a major project on your hands.

When I was renovating my Starcraft, I found Starcraft customer service to be knowledgeable and helpful. There may be no drawings that are shared about the individual framing schedules, existing only for design engineers and production managers. Then again, maybe not. In any case, most wood framed RV's are built as the good DR states. If you can build a dog house, you could frame an RV.

In the case of failed roofs, most damage starts by water infiltration around through holes in the rubber membrane or at it's edge. If left for some time, the wood surrounding the leak point will start to fail. Good news is that the membrane pulls off that easily. Bad news is that some wood particles may be attached to the adhesive on the membrane. The other insidious part of water leaking is that water travels with gravity along framing surfaces and can run for good distances. That means that what started as a roof leak may become a wall framing problem. Careful inspection is necessary.

After you have any damage repaired and the roof membrane reattached, I'd suggest to seal any problem spots with Eternabond tape. It never has to be maintained and won't crack and fail again like a caulk sealant might.

Good luck on your project!

Westend Thanks for the reply. I'm hoping to start in the bathroom area as the leak started at the skylight. I'm hoping that the damage is only in that part of the roof. I have checked the wall area and they seem to be okay. It may be awhile before I finish the project as the trailer is going to Georgia to be a hunt camp with a tarp as a roof.