Aluminum electrical wire was used from 1960 up until 1980. This type of conductor was made because it was a less expensive alternative then copper conductor wire. Aluminum wire is not as efficient a conductor as copper wire was so to compensate a larger wire size had to be used. The main issue with aluminum wire is that it expands when it heats up. This expansion can cause the wire to become loose from its attachment screws. Expansion of the wire causes poor electrical connections between the wire and its terminal. Another issue is that aluminum wire is easy to damage and often was nicked or crimped. When the wire is damaged hot spots can occur.
There are two corrective measures that one can take when aluminum wire is found during the home inspection process. The first one and the one that I recommend is to replace the aluminum wire with cooper conductor. This is an expensive undertaking but at least you will have the piece of mind knowing that the problem wire has been replaced. A second measure is to install special connectors where the aluminum wire is connected to copper wires. These connections are regularly referred to as pig tails. This method is good in theory but poor in practice. What you have now is the addition of many more electrical connections in the home. The more connections and splicing that you have the greater chance of shorting and overheating can occur. In any event when we locate aluminum wire during a New Jersey home inspection you should get a licensed electrical contractor to determine the best corrective measures. Most electrical contractors are going to recommend that the suspect wiring be replaced.
New Jersey Home Inspections performed by a Licensed New Jersey home inspector.