A mechanical room or a boiler room is a room or space in a building dedicated to the mechanical equipment and its associated electrical equipment, as opposed to rooms intended for human occupancy or storage. Unless a building is served by a centralized heating plant, the size of the mechanical room is usually proportional to the size of the building. A small building or home may have at most a utility room but in large buildings mechanical rooms can be of considerable size, often requiring multiple rooms throughout the building, or even occupying one or more complete floors (see: mechanical floor). A mechanical room or a boiler room is a room or space in a building dedicated to the mechanical equipment and its associated electrical equipment, as opposed to rooms intended for human occupancy or storage. Unless a building is served by a centralized heating plant, the size of the mechanical room is usually proportional to the size of the building. A small building or home may have at most a utility room but in large buildings mechanical rooms can be of considerable size, often requiring multiple rooms throughout the building, or even occupying one or more complete floors (see: mechanical floor).