Volkemon, thanks so much for your narrative and photos on what you found. Fortunately I havenít had any leaks so far (knock on wood) but I am paranoid about this occurring. Even though my unit is only about a year and a half old I frequently inspect the roof caulking and have touched it up to try and stay ahead of any issues.One area of concern i have is where the roof and sides mate up with the front and rear fiberglass end caps. I see on the sides in your photos this is where you found areas where water was getting in. Is this just a simple U channel that snaps over the seam or how is it retained? The front and rear caps lap over the side panels. On the rear cap, it appeared that the cap was pop-riveted every 6 inches or so to the body panels. There is a metal track that then was riveted on top of the seam, with rivets that barely went through both layers below. The trim you see on the outside clpis on to the metal track, hiding it. As you mentioned several screws were used are they just screwed in to the outer fiberglass skin or do they depend of the Luan plywood interior panel for their anchor? Since I have not seen this splice joint disconnected other than your photos and I am a little confused as to how it supposed to work. Any clarification you could provide would be greatly appreciated.The screws on the rear cap seam were all added in a previous repair that was done rather poorly. They anchor the surface track into the rear cap and side skins similar to the original pop-rivets. Before my ownership, It would appear that the rear corner hit something. With a new, undamaged coach I wouldnt worry too much about those seams.
I had a VW before too (Winnebago Rialta) and finding parts and service for that teutonic pos was like owning an antique car, something you don't do unless you are mechanically inclined and enjoy working on projects, but really should not be driving on adventures to Anytown USA.
I find it amazing how such a minor water leak at the lower skirt can do so much damage. Not just water but also mold. Fortunately it is in a confined area that is non structural and relatively simple to resolve. This should be a warning to the rest of us. If water is getting inside somehow. Don't delay in finding the cause. Imagine the water damage and mold that often occurs in a typical class C in the cab-over bed area. You had a small confined area, they have it in a massive area. I don't know how people deal with the mold while ignoring the problem.We looked at a few. You are doing great there volkemon.