Our 5'x 8' bathroom remodel includes a new 5' whirlpool tub. It will not be used as a showwer though it will have a hand held "shower" for rinsing/hair washing. We plan to have a 48" high beadboard wainscott on all the walls including the walls above the tub, then painted sheetrock to the ceiling. Is there a preferred method/material that would provide some moisture proofing of the wall surrounding the tub?