Post some pictures of the rot, it is all fixable. Old Mister Bill was the master rv repair guy on here, but even with him gone there are several of us who have worked on some. Unfortunately I don't think that make had anything but a wooden frame, so you need to be careful taking it apart so you can get measurements to figure out how it should go back.
Yep its wood.
This is the part I put the clear flextape on. I need a little more at the right side, or silicone. There wasn't much wood in the wall for the bolts for the trim to go into, something like wood paneling thick. It has rigid styrofoam insulation in there mostly. I guess they tried to build it as light as possible. I can't see the framing very much.
Down below this area, there is an access hatch for the purpose of getting under the tub for wires/pipes and it doesn't look totally rotten, unless I didn't look close.
There is some rot around the fridge, water heater and water inlet. The inner vent for the fridge isn't too bad, i got the trim piece over the seams remounted pretty good by driving extra long screws in. They aren't anywhere near the fridge coils so its safe.
I'm not sure that it's heavily structurally rotted yet, but rather the thin paneling bits. I'm working hard to seal everything I can before it rains a lot again.
But anyway, i can't drive long screws in this spot because they'd go through to the shower, which is directly on the other side of that wall. I tried to look for studs but couldn't see any except by the window. It's thin, flexible fiberglass so its kind of flexy without being totally flat like its supposed to. As long as the flextape sticks, it shouldn't leak. It's the 4" width tape.
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