Hi! We have enjoyed our 1986 class C 21' RV for about 4 years. We added some plywood planks in the front above the driver's seat area to expand sleeping space for our 2 youngest kids. It works great! We found this summer that after a rain when we moved the plywood planks, they were wet on the UNDERside. The bedding was never wet, so I know it isn't leaking from above. We did a water test, and see no visible leaks. Any ideas where the rain might be getting in and seeping up from the bottom? Thanks so much for the help!

