A Floor Drain is a plumbing fixture that is installed in the floor of a structure, mainly designed to remove any standing water near it. They are usually round, but can also be square or rectangular. They usually range from 2 to 12 inches (5.1 to 30.5 cm); most are 4 inches (10 cm) in diameter. They have gratings that are made of metal or plastic. The floor around the drain is also sloped to allow the water to flow to the drain. Many residential basements have one or more floor drains, usually near a water heater or washer/dryer. Floor drains can also be found in commercial basements, restrooms, kitchens, refrigerator areas, locker/shower rooms, laundry facilities, and near swimming pools, among other places.