How to Insulate Old Aluminum Wires

Aluminum wiring became popular in homes built between 1965 and 1973 because it was less expensive than copper wiring. However, aluminum wires are known to cause safety issues due to expansion and contraction. This can lead to loose connections which increase the risk of fires. Therefore, it is important for homeowners to properly insulate old aluminum wires.

Dangers of Uninsulated Aluminum Wires

Aluminum wires expand and contract more than copper wires due to temperature changes. This can cause connections to loosen over time. Loose connections generate heat which can melt the wire insulation and lead to fires.

Some key dangers of uninsulated aluminum wiring include:

Signs You Need to Insulate Aluminum Wiring

Watch for these warning signs that indicate your aluminum wires need to be properly insulated:

If you notice any of these signs, it is critically important to have your aluminum wires inspected and insulated.

How to Insulate Aluminum Wires

Here are the recommended steps for properly insulating old aluminum wiring:

Inspect the Wires

Carefully inspect along the entire length of aluminum wires for cracks, damage, discoloration, or loosening connections. Damaged areas need to be re-insulated.

Clean the Wires

Use a wire brush to thoroughly clean aluminum wires of dirt, oxidation, and corrosion before insulating. This allows insulation to properly adhere.

Apply Insulating Coating

Apply a thick coat of insulating sealant like liquid electrical tape along the entire length of the wire. This seals and insulates wires.

Replace Wire Nuts

Replace old or damaged wire nuts with new CO/ALR rated wire nuts designed for aluminum and copper wiring. This prevents loose connections.

Use Anti-Oxidant Paste

Brush anti-oxidant paste on wires and connections. This prevents oxidation that leads to loose connections.

Insulate Connections

Wrap high-quality electrical insulating tape around all wiring connections to protect from heat buildup.

Label the Wires

Clearly label insulated aluminum wires to alert future homeowners. Write "Aluminum Wiring" along the insulation.

Properly insulating old aluminum wiring requires patience but is critical for safety. If unsure, consult a licensed electrician to check for damage and insulate areas needing repair. Your diligence can prevent wire hazards.

FAQs About Insulating Aluminum Wires

Should I replace aluminum wires instead of insulating them?

Replacing aluminum wiring with copper is the best option, but can be very costly. Properly insulating wires is an affordable alternative to increase safety. But insulation is only temporary - replacement may still be needed down the road.

How much does it cost to insulate aluminum wiring?

If doing it yourself, the material costs are minimal - around $50-$100. If hiring an electrician, costs range from $90 to $250 per hour depending on local rates. Get quotes from 3+ electricians.

How long does aluminum wire insulation last?

With proper installation, insulating coatings and tapes can last 15-20 years before needing replacement. It's important to periodically inspect for cracking insulation.

Should I use twist-on connectors or wire nuts?

Wire nuts rated CO/ALR are highly recommended as they help prevent loosening of connections with aluminum wires. Twist-on connectors are more prone to loosening over time.

Can I use electrical tape alone to insulate connections?

While tape provides insulation, it should not be used alone on connections. The adhesive can fail over time. Use insulating coating and CO/ALR rated wire nuts, and tape those connections.

Taking the proper steps to insulate old aluminum wiring helps reduce the risks of electrical hazards and fires. Be diligent in inspecting wires and addressing any damage found. If ever in doubt about safety, consult a professional electrician.