Today we’re going to talk about aluminum wiring. This is a hot topic these days and we wanted to give you a bit of information.
In the mid 1960’s the price of copper increased dramatically and aluminum became the choice product for wiring houses. Aluminum wiring has been implicated in house fires, either because of improper installation or a difference in the expansion capabilities between the wiring and the termination techniques.
There are several problems inherent in aluminum wiring. One is aluminum oxidation. Oxidation happens when the metal is exposed to air, and as oxide is an insulator rather than a conductor this can hinder the flow of electricity . However, as long as there is a proper connection between the wire and the terminal no air will penetrate the connection to form oxide.
Another problem is the joining of aluminum and copper wiring. Since they are dissimilar metals corrosion of these connections can occur over time causing the connection to become unstable. However, special connectors have been created to help alleviate this situation. In 2011 AlumiConn lug connectors were approved for use in addressing this particular issue. Here at SJO Electric that is what we recommend and use for permanent repair. This is a procedure that is often called pig-tailing and can be efficient and affordable.
Last but not least is a problem referred to as “creep.” This is an issue that occurs in pre-1970 solid aluminum wiring. Creep refers to the tendency of sold aluminum wire to permanently deform and relax over time under thermal load. When this happens the connections may become loose or otherwise damaged creating a need for repair or replacement.
Many incorrectly believe that repairing older pre-1970s aluminum can be done by replacing electrical devices such as switches and outlets with ones that are rated for use with aluminum wire. These modern devices are tested and approved using modern aluminum wire, which is very different than older pre-1970s aluminum wire which expands and contracts much more making it more susceptible to oxidation and creep. Using modern aluminum rated devices for older aluminum wiring should only be considered as an emergency repair.
Having aluminum wiring in your house does not always mean you have potential for a house fire. Some aluminum wiring is safe and can be left as is. But that is not always the case. Please, don’t believe you can address the problem yourself. Have a licensed electrician check your wiring if you have doubt and have it addressed properly.
Thanks and have an electrically charged day!!!
The team at SJO Electric