Homes built before 1972 with solid aluminum wiring are "55 times more likely to have one or more wire connections at outlets reach Fire Hazard Conditions than homes wired with copper,” according the CPSC (Consumer Products Safety Commission). The problem is due largely to aluminum’s high coefficient of expansion compared to copper, although oxidation is also a problem. When aluminum heats up and expands, it begins to loosen the wire connections at receptacles, switches, and junction boxes. The loose connection increases electrical resistance at that point, which makes the connection hotter and looser, and the cycle repeats itself until it becomes hot enough to ignite nearby flammable building materials and start a house fire. 

    We don’t see too many homes anymore with solid aluminum wiring that has not been fixed by installing COPALUM pigtails or totally replaced with copper. But they are still out there, and usually in older pre-HUD mobile homes. It’s important to remember that only SOLID aluminum wiring from the mid-1960s to 1972 is a fire hazard. MULTI-STRAND aluminum wiring is code-compliant and often used for service cables and major appliance circuits.

    Here’s links to our answers for Frequently Asked Questions (FAQ) about ALUMINUM WIRING:

• I heard that aluminum wiring is bad. How do you check for aluminum wiring? 

• Does a home inspector check for aluminum wiring?

• When did they stop using aluminum wiring? 

• When was aluminum wiring banned in mobile homes?

• What is the gooey stuff on some of the wire connections in the electric panel?

• Should I buy a house with aluminum wiring? 

• What are typical aluminum service entrance wire/cable sizes for the electrical service to a house?

• Do any pre-1960 houses have aluminum wiring?

• Can a home inspector tell me if the wiring in a home is safe?