The distribution system for house and tenant power and lighting including the heating, ventilating, air conditioning, plumbing, sprinkler, and snow-melting systems, elevators, moving stairs, signs, interior and exterior lighting, and the control, communication, and signaling systems which include the public address, clock, bus dispatching, bus counting, fire alarm, and sprinkler supervisory systems, as well as the watch engineer's supervisory control system, are discussed.