Trackrig, Thanks for the advice. Plywood was damaged in two places. One place was was under one of the dinette cushions. I never experienced any problem under any of the cushions in the past, but the plywood on which it sat was damp and black. It was also where one of the chains was anchors to attach to the truck bumper. It was protected from rain and open to ventilation. The other piece of plywood was under the sink. There was no leak from the sink or plumbing, but there was a cast iron griddle sitting on the shelf and when I picked up the griddle, it, too, was black and soggy, only under the griddle, not under any other pots or skillets, etc.