I've got a commercially built squaredrop that I've been incrementally rebuilding to make it closer to what I want and also to improve the build standard. It started leaking from the roof at the end of last fall and the crazy warm weather this week has me trying to reseal the roof. The roof currently is 1/4" ply on the inside, 1.5" of styrofoam, and then a thin aluminum skin on the outside. Since it's a 6x10 trailer, I've got the edges/corners plus two transverse seams to deal with. The factory setup is that the corners and the two seams have aluminum extrusions covering them, screwed into the framing down their center. Then a vinyl insert covers the screw heads. To be water tight, the RV trim has to be caulked both at the outside edges of the aluminum extrusions where they rest against the aluminum skin of the trailer and also at the seam between the vinyl insert and the aluminum extrusion. After doing my best to scrape out the existing degraded silicone caulking, I'm replacing it with Lexel, since I've had very good luck with it on my house. However, this is a TON of work and I have no interest in doing this yearly!
Is there a better product that I can replace this all with? I'd love to rip off the RV trim extrusions and just cover the skin seams in something more permanent. The only thing I've come up with is making the camper a fiberglass hat to wear and that just seems like a ton of work. If I'm going to put that much into it, I might as well just build a foamie exactly the way that I want it. Is there some product I can switch to that makes this a non-issue?