In the late 1960s and early 1970s, copper prices were very high compared to aluminum, so contractors and electricians started using aluminum to lower their costs. Although no longer used in distribution circuits (which are the smaller wires in the home carrying electricity to the sockets and switches), aluminum wiring is still used today for certain applications. For instance, it can be found on 240 volt circuits for stoves or dryers and used as the main service entrance wire from the road to the house.
The Dangers of Aluminum Wiring
Aluminum’s conductivity is not as strong as copper, so contractors used thicker wire. Today your typical socket or switch is wired with 14-gauge copper, while aluminum requires a 12-gauge wire. If aluminum is connected to a fixture not designed for it or if copper and aluminum wires are connected together, then they can react with each other. This can cause the connection to fail, potentially disconnecting and overheating, sparking or even catching fire. Symptoms of this can sometimes be seen by a discoloration of the receptacle, flickering lights or the smell of hot plastic insulation.
What to Do if You Have Aluminum Wiring
Aluminum wiring if installed correctly will work as safely as any other type of wiring. If a home has aluminum wiring and you think that problems may exist, advice from a qualified electrician that has knowledge about aluminum wiring would be the best place to start.