My PUP is showing her age and the effects of the humid southern climate. I already had to replace a section of the floor and now another spot is getting pretty soft. I also have several wall sections that have come loose from the floor & I suspect that rot is part of the culprit. The short sections of wall, front driver side & rear passenger side are loose. The front one isn't really affecting too much because the bunk is well supported by the brace poles. But, the rear one, which borders the door, is allowing the bed to sag a bit and the door not to align properly. In addition, because of the common cracking of the corners on the Flagstaff roof, I have a bad piece of wood in the leading edge of the roof. Given all of these issues, I think that I'm going to attempt a complete floor-up rebuild soon (maybe this winter). I'm thinking that I can certainly do the rebuild for less expense than replacing the entire PUP. While I'm at it, I'll probably do some mods in the interior by replacing some cabinets and possibly removing the shower unit and hot water heater which I never use. Here are a few thoughts & questions on the project that I'm looking at: I'm thinking of going for rugged construction within the limits of my frame and axles. So, I'm looking at materials that should hold up better than the stock stuff. What are suggestions for floor materials? I see many use exterior plywood rather than OSB. Has anyone used 3/4 or 5/8 plywood for the walls? I'm considering adding additional exterior access doors to be able to load/restock supplies without having to pop up. I'm also considering adding a bit more depth to the roof sides to allow for thicker mattress pads or toppers. Has anyone done this? Obviously, I would like to reuse the exterior siding & diamond plate. I'm thinking that contact cement is what is used to reattach? I'll keep an eye on this thread and be reading all of the other rebuild threads. Once I start the project, post a thread on the progress.