Linen closet: A tall, narrow closet with shelves in a bathroom used for storing towels,sheets,washcloths, and toiletries. Utility closet: A utility closet is a closet most commonly used to house appliances and cleaning supplies. Most of the time, you may find a hot water heater and possibly the furnace. The closet may have shelves for storing appliances on top where they are out of the way.