Aluminum Wiring in Wisconsin: Safety Risks and Solutions

Aluminum Wiring: A Hidden Risk in Wisconsin Homes

Between roughly 1965 and 1973, a copper shortage led homebuilders across the country — including throughout Wisconsin — to use aluminum wiring for branch circuits in residential construction. At the time, it seemed like a perfectly reasonable substitution. Decades later, we know that aluminum branch circuit wiring is a documented fire hazard that affects thousands of homes in Racine, Kenosha, Milwaukee, and the surrounding area.

If your home was built during this period, understanding the risks and your options is important for your family's safety, your insurance coverage, and your home's value.

Why Is Aluminum Wiring a Problem?

Aluminum is an excellent conductor and is used safely in many electrical applications — including the main service entrance cable in virtually every home. The problem is specifically with aluminum branch circuit wiring (the 15-amp and 20-amp circuits that run to your outlets, switches, and fixtures). Here is why:

• Higher coefficient of expansion: Aluminum expands and contracts more than copper when it heats and cools during normal use. Over thousands of heating and cooling cycles, this loosens connections at outlets, switches, and wire nuts.
• Oxidation: When aluminum is exposed to air, it forms aluminum oxide on the surface. Unlike copper oxide (which is conductive), aluminum oxide is resistive. This creates heat at connection points.
• Softness: Aluminum is softer than copper. When screwed down at a terminal, it can deform and creep over time, leading to loose connections.
• Galvanic corrosion: When aluminum contacts copper (such as at a standard copper outlet), a chemical reaction occurs that degrades the connection over time.

The result of all these factors is the same: loose, high-resistance connections that generate heat. The Consumer Product Safety Commission (CPSC) has found that homes with aluminum wiring are 55 times more likely to have fire-hazard conditions at outlets than homes with copper wiring.

How to Know If Your Home Has Aluminum Wiring

There are several ways to check:

• Check the visible wiring. Look at the wiring in your panel, attic, or unfinished basement. Aluminum wire is silver in color (copper is, of course, copper-colored). The cable jacket may be stamped with "AL" or "ALUMINUM."
• Check the panel. Open your panel cover (with the power on, but do not touch anything inside) and look at the wires connected to the breakers. If the branch circuit wires are silver rather than copper, you have aluminum wiring.
• Check the home's age. If it was built between 1965 and 1973 in Wisconsin, there is a significant probability of aluminum wiring.
• Have an electrician inspect. If you are unsure, a licensed electrician can confirm the wire type in minutes.

Approved Repair Methods

There are three recognized approaches to addressing aluminum wiring, listed from most effective to least:

Complete Rewire

Replacing all aluminum branch circuit wiring with copper is the most thorough solution. It completely eliminates the hazard. However, it is also the most expensive and disruptive option. A full rewire of a typical Wisconsin home costs $10,000 to $25,000, depending on the home's size, accessibility of the wiring, and whether walls need to be opened. For many homeowners, this is impractical.

COPALUM Crimp Connectors

The COPALUM method is the CPSC's recommended permanent repair. It involves attaching a short piece of copper wire to the end of each aluminum wire using a special crimp connector and a powered crimping tool. This is done at every outlet, switch, fixture, and junction box in the home.

The COPALUM repair can only be performed by an electrician trained and certified in the COPALUM process, using the proprietary AMP tool. The cost typically runs $3,500 to $7,000 for a whole house, depending on the number of connection points. The COPALUM repair is considered a permanent fix by the CPSC and most insurance companies.

AlumiConn Connectors

AlumiConn connectors are a more recent alternative that the CPSC has also recognized as an acceptable repair. These are set-screw-type connectors that create a reliable aluminum-to-copper connection. They do not require a specialized tool, so any licensed electrician can install them.

An AlumiConn repair typically costs $2,500 to $5,000 for a whole house. While slightly less expensive than COPALUM, AlumiConn connectors require more space inside the electrical box, which can be an issue with older, smaller boxes.

Insurance Implications

Aluminum wiring and insurance is a growing concern in Wisconsin:

• Some insurance companies will not write new policies on homes with unmitigated aluminum wiring.
• Some carriers require an inspection and proof that an approved repair method (COPALUM or AlumiConn) has been completed.
• Some carriers charge higher premiums for homes with aluminum wiring — often $300 to $800 more per year.
• During a home sale, the buyer's insurance requirements can force the seller to address aluminum wiring before closing.

If you are buying or selling a home with aluminum wiring in Racine, Kenosha, or the surrounding area, get ahead of the insurance issue early in the process. A proactive inspection and repair plan is far better than a last-minute scramble that could delay closing.

What NOT to Do

Some approaches that are sometimes suggested are inadequate or dangerous:

• Standard wire nuts: Regular wire nuts are not rated for aluminum-to-copper connections and will not solve the problem. Even "AL-rated" wire nuts (purple wire nuts) are considered a temporary repair by the CPSC, not a permanent solution.
• Anti-oxidant compound alone: While anti-oxidant paste (like Noalox) is a helpful part of a proper aluminum connection, it is not a standalone fix.
• Ignoring the problem: Aluminum wiring does not get safer over time. The connections continue to degrade with every heating and cooling cycle.
• Pigtailing with standard methods: Connecting a copper pigtail to an aluminum wire with a standard wire nut is not an approved repair and may actually increase the risk.

Signs of Trouble

If your home has aluminum wiring, watch for these warning signs that connections are deteriorating:

• Warm or hot outlet or switch cover plates
• Discoloration or melting around outlets or switches
• Flickering lights not tied to appliance startup
• A burning or plastic smell near outlets or switches
• Outlets or circuits that work intermittently
• Sparking when plugging in or unplugging devices

Any of these signs in a home with aluminum wiring should be treated as urgent. Turn off the affected circuit and call a licensed electrician immediately.

Frequently Asked Questions

Is all aluminum wiring dangerous?

No. Aluminum wiring used for the main service entrance (the large wires from the meter to the panel) and for large appliance circuits (240-volt dryer, range, AC circuits) is safe and standard. The hazard is specifically with aluminum wiring used for 15-amp and 20-amp branch circuits — the circuits that serve your outlets, switches, and lighting. These smaller gauge aluminum wires are where the problematic connections occur.

Do I have to rewire my entire house?

No. A complete rewire is the most thorough solution, but approved methods like COPALUM crimp connectors and AlumiConn connectors can safely mitigate the risk without replacing the wiring itself. These methods address the problem at the connection points, which is where the hazard exists. Most insurance companies accept COPALUM or AlumiConn repairs as adequate mitigation.

Will fixing aluminum wiring increase my home's value?

Yes. Mitigated or removed aluminum wiring eliminates a major concern for buyers, inspectors, and insurance companies. In the Racine and Kenosha real estate market, aluminum wiring is consistently flagged during home inspections. Having documentation that the wiring has been professionally addressed with an approved method removes a significant negotiation point and can prevent deals from falling through.

Concerned about aluminum wiring in your home? Call Couillard Electric at (262) 618-2851 for a free estimate. We perform aluminum wiring inspections and COPALUM/AlumiConn repairs throughout Racine, Kenosha, and southeastern Wisconsin.