Current codes require separate circuits for all fixed appliances (range, dryer, hot water heater, furnace) and convenience outlets located along the wall within six feet of any potential need. Older homes often have fuse boxes that have been expanded to accommodate additional loads. In the early and mid-sixties, three-pronged outlets became required by code for new construction. This third wire provides additional protection against electrical shock.

Ground Fault Interrupt Circuits (GFI's) came into use in the early seventies. These circuits are designed to detect any ground current fault and immediately disconnect the circuit. Bathrooms, outdoor fixtures and outlets near water were the first to require these devices. Kitchen outlets have since been included. These circuits are often identified by the test and reset buttons located on the receptacle.

Aluminum branch circuit wiring was briefly used in the sixties and early seventies. Because of potential hazards, the use of aluminum wiring is now severely restricted. The improper installation of switches, receptacles and fixtures can cause overheating and fire hazards.

A thorough survey of the electrical system should always be undertaken when contemplating additions and/or remodeling a house with an older electrical system.