How to Use Aluminum Wiring Safely in Older Homes

How to Use Aluminum Wiring Safely in Older Homes


Aluminum wiring became popular in American homes built between 1965 and 1973 because it was less expensive than copper wiring. However, aluminum wiring has been linked to certain fire hazards if not properly installed and maintained. As the owner of a home with aluminum wiring, you can take steps to use it safely. This article provides an in-depth look at aluminum wiring and how to use it safely in older homes.

What Is Aluminum Wiring?

Aluminum wiring consists of pure aluminum or an aluminum alloy rather than copper. It was used for both 120-volt and 240-volt circuits during the 1960s and 1970s.

Key characteristics of aluminum wiring:

Aluminum wiring is identified by the color and words printed on the outer plastic insulating jacket:

Potential Hazards of Aluminum Wiring

The potential fire hazards associated with aluminum wiring occur due to:

Other factors that increase fire risks with aluminum wiring:

Inspecting for Aluminum Wiring

To use aluminum wiring safely, the first step is to inspect your home to verify if aluminum wiring was used.

Warning signs your home may have aluminum wiring:

Thoroughly inspect the electrical panel, outlets, switches, and light fixtures. Use a flashlight to better see the writing printed on wire insulation. Pay special attention to areas where appliances pull a lot of electricity like the kitchen, laundry room, and garage.

If your home has combination wiring (some copper and some aluminum), be sure to identify which circuits have aluminum wiring. This will help you focus mitigation efforts on the aluminum wiring only.

Mitigating Aluminum Wiring Hazards

If your home inspection confirms aluminum wiring, several steps can be taken to mitigate fire hazards:

1. Hire an Electrician

Professionally replacing aluminum wiring with copper wiring is the best solution, but also the most expensive. If this isn't feasible, hire a qualified electrician to inspect all connections and perform the following mitigation techniques. Improper work could make hazards worse, so always use a licensed electrician experienced with aluminum wiring.

2. Repair Loose Connections

The electrician should tighten any loose connections and outlet or switch screws/terminals. Special care must be taken to not overtighten and damage wires. A special antioxidant grease or lubricant should be used on aluminum wire terminations to prevent future loosening.

3. Pigtailing

Aluminum wires can be attached to short lengths of copper wire called "pigtails" using special connectors. The pigtails are connected to outlets and switches. This prevents direct contact between the aluminum wire and the device's copper screw terminals.

4. Replace Outlets and Switches

Standard outlets and switches are incompatible with aluminum wiring. The electrician should replace old outlets and switches with models labeled "CO/ALR". These are designed to safely work with aluminum wiring.

5. Circuit Breaker Upgrades

Standard circuit breakers may be improperly rated for aluminum wiring. A qualified electrician should evaluate and potentially replace breakers with appropriate models.

Ongoing Maintenance and Monitoring

Proper maintenance and monitoring is crucial for continued safe operation after mitigating aluminum wiring hazards in your home.

Is Aluminum Wiring Always Unsafe?

While aluminum wiring does present fire hazards if not properly addressed, the risks can be greatly reduced by following proper safety practices. Homeowners should not panic if they discover they have aluminum wiring, but rather take prudent steps to use it safely. With the right precautions and maintenance, aluminum wiring can be used safely in older homes.