Hardwiring Your Home With Aluminum Wires

I recently decided to rewire my 1970s home to upgrade the electrical system. Upon inspecting the wiring, I discovered that most of it consisted of aluminum rather than the more standard copper. This led me down a rabbit hole of research to determine if I could safely keep the existing aluminum or if it needed to be fully replaced. Here's what I learned about aluminum wiring through my journey.

Why Aluminum Wiring Was Used

During the 1960s and 1970s, copper prices were very high and there was also a copper shortage at times. As a result, many homes built during this period utilized wiring made from aluminum rather than copper. Aluminum was seen as an affordable alternative that could conduct electricity nearly as well.

There are a few key reasons why builders opted for aluminum:

• Aluminum was cheaper - Copper was priced very high at the time, making it less affordable. Aluminum wiring was estimated to save builders up to 50% compared to copper.

• Aluminum conducts electricity effectively - Aluminum is an excellent conductor, carrying electricity nearly as efficiently as copper does. This made it seem like a feasible substitute.

• Aluminum was easier to work with - Aluminum wiring is more lightweight and flexible compared to copper. This made installation simpler than working with rigid copper wires.

Though cost savings and availability drove the initial use of aluminum wiring, it was seen as an acceptable solution at the time since aluminum can effectively carry electrical current.

The Downsides of Aluminum Wiring

However, over time it became clear that aluminum wiring has some important downsides compared to copper:

• Higher resistance - Aluminum has a higher resistance than copper, which means more energy is lost as heat during transmission. This requires thicker wires to carry the same electricity.

• More prone to corrosion - Aluminum oxidizes more easily than copper, especially in connections. This can increase resistance and cause wires to overheat.

• More likely to loosen from connections - Aluminum wires expand and contract more with temperature changes. This can cause connections to loosen over time, resulting in overheating issues.

• Higher failure rates - Homes wired with aluminum have a failure rate for connections that can be 20 times higher than copper wiring. Loose connections cause problems.

While it seemed like an inexpensive solution originally, the potential hazards of aluminum wiring became more apparent over decades of use. Preventing problems requires properly maintaining connections.

Inspecting Aluminum Wiring in My Home

Since my home was built in the early 1970s, I wasn't surprised to find that all of the wiring consisted of aluminum. This included:

• Wiring connecting the electrical panel to outlets and switches
• Wiring for the light fixtures
• Appliance wiring running to the furnace, water heater, and AC unit
• Any other permanent wiring throughout the home

I systematically went through the house and inspected each electrical connection I could access. I looked for:

• Discolored or warm connections - A sign of overheating

• Corrosion - Any white or dark colored oxidation

• Loose connections - Verified tightness of all screws and contacts

• Original equipment - Outlets, switches, and breakers rated for aluminum

Thankfully, I didn't find any glaring issues with my wiring. No discoloration or significant corrosion. However, I did find a few loose wire nut connections that I tightened.

Overall, the aluminum wiring appeared in reasonable condition given its age. But I knew I still needed to take precautions going forward.

Options for Making Aluminum Wiring Safer

I had to decide whether to completely rewire my home with copper or find ways to make the existing aluminum wiring acceptably safe. Here are a few options I considered:

Completely Rewiring the Home

• Pro: Safest option, avoids any risks of aluminum wiring

• Con: Extremely expensive ($10k+) and damaging to the home

Use Copalum Crimp Connectors

• Pro: Simple for DIY, joins copper to aluminum

• Con: Still have most aluminum wiring

Pigtail Wiring Method

• Pro: Also DIY friendly, adds copper pigtails

• Con: Still largely aluminum, very time consuming

AlumiConn Connectors

• Pro: Professionally converts connections to copper

• Con: Only fixes connections, not whole runs

Adding Arc Fault Circuit Breakers

• Pro: Affordable safety upgrade to panel

• Con: Doesn't fix underlying issues

I ultimately decided that a combination of copper pigtailing some connections and AFCI breakers in the panel was the best solution for me. This significantly improves safety without a huge expense.

Key Tips for Safe Aluminum Wiring

If you decide not to fully rewire, here are some tips to follow:

• Use the twist-on connectors specifically rated for aluminum when splicing wires

• Pigtail connections with copper whenever possible

• Make sure outlets, switches, and breakers are rated CO/ALR for aluminum

• Go with AFCI breakers to protect against loose wiring faults

• Check for any hot outlets indicating connection issues

• Shut off and reconnect wires that feel more than warm to the touch

• Periodically check wiring connections for any signs of issues

While aluminum wiring can certainly be maintained safely, it does require diligence and the right components to prevent hazards. Following these guidelines, upgrading certain connections, and monitoring everything regularly can go a long way towards protecting your home.

Is It Necessary to Rewire My Whole House?

The question of whether to do a complete rewire comes down to a safety vs cost analysis:

• A full rewire provides maximum safety by removing all old aluminum wiring. However, it is also extremely expensive.

• Upgrading connections, using AFCI breakers, and monitoring wiring often provides adequate safety at a fraction of the cost.

According to the Consumer Product Safety Commission, homes only need to be fully rewired if:

• There are visible signs of improper connections

• Wiring is incorrectly installed or otherwise faulty

• A professional electrical inspector recommends it

For many homes that just have old aluminum wiring, focused improvements are often sufficient to address safety concerns. The wiring just needs to be properly maintained and monitored.

Key Takeaways on Aluminum Home Wiring

Upgrading my 1970's home sparked an extensive learning journey on safely maintaining aluminum electrical wiring. Here are the key takeaways:

• Aluminum wiring requires meticulous connections to avoid resistance and overheating

• Improving certain connections with pigtails and AlumiConn adapters can help significantly

• Using AFCI outlets and breakers provides important fire protection

• It's critical that all switches, outlets, and breakers are rated for aluminum

• Ongoing monitoring of wiring condition allows problems to be addressed

• For most homes, selective improvements reduce risks at a reasonable cost

While aluminum wiring has downsides compared to copper, it can be maintained safely with care and upgrades. This makes full rewiring optional, not required. My journey taught me how to work with aluminum wiring in a way that allows me to keep the benefits of my home's original construction while still protecting my family.