Well, I suppose it was bound to happen given the weather. (Rain since March!) I have become aware of a problem in two of the cars in the collection developing mildew on the inner surfaces. I want to be sure to wipe out any chance of it spreading to the rest of the cars. Also kill it where it already has formed. The structure is 60' x 26' with a concrete floor, framed walls and steel roof. The walls and roof were sprayed with foam insulation. Finish on the walls is painted sheetrock and Luan plywood on the ceiling. My initial information indicates a chlorine solution needs to be used. Anyone have a similar experience or input? Structure has not had this problem for the past 5 years, only after all the rain this year. Located in central NY.