Aluminum Wiring 
Was installed and used in the building trade during the late 1960's and early 1970's. It was used as an alternative material to replace copper, a material that was soaring in cost, and inflating the prices of new construction.  After the industry discovered problems with the use of aluminum, they began to manufacture a product called copper clad. Copper clad was a product made of aluminum with a thin coating of copper applied in hopes to alleviate the problems associated with pure aluminum conductors.  This process proved unsuccessful as well, and soon aluminum was no longer the choice of preference in the electrical trade.

Is aluminum wiring illegal to use? 
No, aluminum conductors are still sometimes used in applications that require a larger size conductor. However, these applications are mostly limited to single use circuits, and are used in situations requiring a large feeder or service entrance. Copper conductors is the wiring method prefered in residential applications throughout this part of the country. However, power utility companies still use aluminum conductors as a service drop from the utility pole to the building or home.

If my house has aluminum wiring, do in need to rewire it?
No, rewiring is not necessary. The problem with aluminum wiring is not in the conductors itself, but at the point of attachment to a device.  Aluminum is a very porous material, which allows it to easily expand and contract according to temperature changes. Along with expantion, the normal everyday vibrations throughout the building, allows the connections to work loose.  A loose electrical connection produces heat. The more heat produced will eventually cause the conductor to burn, thus causing the possibility of a fire. This condition can occur without tripping the circuit breaker.

What is "Pigtailing"?  
Pigtailing was a method used to get the aluminum conductors off the connection point of the device.  A short piece of copper wire was connected to the aluminum conductor with the use of a wire connector. The connector was treated with a anti-oxidizing compound before being used. Then the copper conductor (pigtail) was connected to the device.

Is "Pigtailing" legal?
Yes, this method has neen apporved and accepted by the National Electrical Code, as long as a special connector is used. This connector is refered to as "COPALUM" connector, and is purple in color.

What is my solution?
The most accepted and perfered way to address the problem of aluminum wiring is to change all the outlets and switches in the house with a special device designed to accept aluminum wiring at the contact point.  This device is referred to as a "CO/ALR" device.

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