My question is about wall coverings for the tub/shower area. My house was a kit that someone built himself back in the 1950's. I have a in-floor cast-iron tub. There is also a window positioned in the middle of the outside wall in the shower area just above the tub. This feature and the fact that the area is an odd size prevents using a shower enclosure. I want to know where and if some kind of plastic or vynil wall board exists to cover the walls. The laminated particle board that is up there now is flaking and rotting from water damage. If something like this exists where would I find it and how much could I expect to spend?