Aluminium wiring
Residential Installations
Aluminium wiring was extensively used in homes between 1965 and 1976. Problems have been reported from the overheating and failure of aluminium wiring terminals resulting in insurance concerns.
The signs of these problems are:
- the discolouring of the wall receptacle,
- flickering lights, or
- the smell of hot plastic insulation.
Although not all aluminium wiring is hazardous, the safety issues with aluminium wire usually involve the 110-volt circuits used for outlets and lights. In some cases connections worked loose and the wire overheated, which sometimes caused a fire. Consequently, the use of 110-volt aluminium wiring was abandoned, and older homes with this type of wiring typically warrant upgrades at connection points or junction boxes.
The use of aluminium wiring is common and acceptable for 220-volt circuits, provided the connected device is rated for aluminium wire. Heating equipment, air conditioners, clothes dryers and electric stoves are examples of acceptable hardware.
As long as the wire ends are protected with a corrosion resistant compound, concern over the presence of aluminium wire may not be justified. In fact, the majority of electric utility companies use aluminium cable for their main service lines. In all likelihood, the power lines coming to your home are aluminium.
What to do
To confirm the safety of the aluminium wire in a home you may be purchasing, have a home inspector and electrician meet at the property to confer and to compare findings. It is recommended that a qualified electrical contractor inspect the electrical system, including all connections. The insurance company may insist on a complete electrical inspection by a certified electrician, rather than a report from a home inspector.
Source: CREA