I'm not sure if I am posting in the right forum or not, so I apologize in advance. My topic kind of fits a few places I suppose. Long story short, my 2017 Keystone Sprinter 33bh has water damage. I...
marine ply or advantech would work. advantech will be easier to find and cheaper if it is the right thickness. just don't use pressure treated it can corrode metal. also try to cut out a section that will overlap the frame where the edges meet.