High-Impact Polypropylene Floating Basement Tiles are designed especially for your basement. Because basements tend to be humid, these interlocking tiles are designed with grooves underneath for air and water passage. This is needed so that mold does not build up between the tiles and the concrete floor. They can easily be cleaned using a sponge mop with mild soap and water. They are made from High-Impact Polypropylene material that can withstand high rollover weight capacity.