Never had any washboards in my B36(2002), instead I bought some white rubber matting with a floral design on it from a caravan accessory shop. The matting is easy to cut to shape, it allows water to drain through it to the shower sump, and doesn't squeak at all. Periodically it goes into the washing machine at home, or gets a squirt of bleach if it starts to stain. Also it's kind on the feet, particularly in cold weather for that middle of the night trip !!