Basically we built a frame for the front if the tub and covered it with beadboard wainscoting and MDF moldings (a plastic, waterproof, rot proof version of the classic wood moldings). On the top edge of the tub we placed a board made from PVC to finish off the built-in look. We also added MDF boards on the side of the tub going up the wall to further anchor it in place. What is behind a beadboard trim to update and upgrade old bathtub