What to Do if You Have Aluminum Wiring in Your Home

Many homes built in the 1970’S were wired with aluminum wiring within their walls. Most all these homes have or will experience various electrical problems. The problem lies in the fact that aluminum wire tends to expand and contract at a greater ratio than the more commonly used copper wire. This excessive expanding and contracting tends to loosen the connections at switches, receptacle outlets, and other electrical devices. While aluminum wiring is still widely used for electrical wiring, and if installed properly and as per code, it is completely safe. However older homes that have aluminum wiring need to be inspected and repaired. If properly done an older aluminum wiring system can made safer than many new homes.

Many Electricians, Building Inspectors and other professionals have held onto the outdated notion that pigtailing with an antioxidant compound is the way to make these repairs. Pigtailing is the process where short pieces of copper wire are connected to the aluminum wiring with the use of wire-nuts and an antioxidant compound. The short pieces of copper wire are then attached to the switch or receptacle outlet.

The use of pigtails MUST NOT be utilized in this application. Further, the US Consumer Product Safety Commission States: The first temporary repair involving pigtailing with a twist-on connector. The effectiveness of “pigtailing” using twist-on connectors has been evaluated by CPSC staff. In CPSC-sponsored laboratory testing and life tests, substantial numbers of these connectors overheated severely. Surveys of and statements made by electricians and electrical inspectors confirm the highly variable and often poor performance of twist-on connectors with aluminum wire. It is possible that some pigtailing “repairs” made with twist-on connectors may be prone to even more failures than the original aluminum wire connectors. Accordingly, CPSC staff believes that this method of repair does not solve the problem of overheating present in aluminum-wired branch circuits. Also, none of the manufacturers of antioxidant compounds list their product for this purpose. Antioxidant compound is a product used on aluminum to prevent spalling.

The other repair recommended by the industry is to use switches and receptacles labeled “CO/ALR.” These devices are intended for direct connection to aluminum wire, although they can be used with copper or copper-clad wire. CO/ALR devices perform better with aluminum wire than non-CO/ALR devices when installed carefully and according to best electrical practices. This process in conjunction with replacing your existing breakers with Arc Fault (AFCI) type breakers, will make your home safe from most electrical fires.

All receptacle outlets and switches are to be replace with devices that are “Rated” and “Listed” for use with aluminum wiring. As per the 2017 NEC, Article 406.3(C) Receptacles for Aluminum Conductors: Receptacles rated 20 amperes or less and designed for the direct connection of aluminum conductors shall be marked CO/ALR. NOTE: The aluminum conductors are to be directly connected, the use of pigtails is in violation of the code and must not be utilized.