How can you tell if a house has aluminum wiring?
You can often tell a house has aluminum wiring by looking at the cable jacket, which may be printed with AL or the word aluminum, and by the silver color of the bare wire in the panel or outlet boxes. Do not open boxes with power on. A licensed electrician can confirm it safely.
Copper wire has a warm, orange tone, while aluminum looks silver and dull. The cable jacket in the attic or near the panel is often the easiest place to read the markings, since an attic inspection does not require touching any connection.
Home inspection reports sometimes note aluminum wiring. If you bought a house from the 1960s or 1970s, check that report, and ask the electrician for a written finding if you have any doubt.
Why is aluminum wiring a concern?
Aluminum wiring is a concern because aluminum expands and contracts more than copper as it heats and cools, which can loosen connections at outlets, switches and splices over time. Loose connections create heat, and heat at a connection is a recognized fire risk.
Aluminum also forms an oxide layer that resists current, and it can react with some metals used in older devices. Outlets and switches not made for aluminum can make this worse.
In Arizona, attics and wall cavities see large temperature swings, which adds stress to connections. That is one reason aluminum wiring deserves attention here, even though the wire itself may have worked for decades.
Which West Valley homes might have aluminum wiring?
Homes built from about the mid 1960s through the mid 1970s are the most likely to have aluminum wiring. In the West Valley, that includes some older Glendale neighborhoods and early Sun City homes, since Sun City began in 1960. Homes built later, such as in Sun City West, usually have copper.
Age alone does not settle the question. Many homes built in this window have copper, and some have additions or remodels that mixed wiring types. Only an inspection of the actual wire tells you.
Warm outlets or switch plates, flickering lights, a burning smell, or a faint plastic odor near outlets are warning signs. Stop using that circuit and call for service.
What are the options if a home has aluminum wiring?
If a home has aluminum wiring, the options generally include replacing the wiring with copper, or having an electrician install approved connectors or devices rated for aluminum at the connection points. The right choice depends on the condition of the wiring, the budget and how much of the home is affected.
A licensed electrician can inspect outlets, switches and the panel, and recommend a path. Partial repairs may be a sensible start, while full rewiring suits homes with other problems like two prong outlets or an outdated panel.
Do not swap devices or use wire nuts that are not rated for aluminum. Vortech provides licensed electrical inspections and repairs for older homes across Glendale, Peoria, Sun City and Surprise.
More questions: Rewiring, Outlets and Switches: 12 Most Asked Questions