Aluminum vs. Copper Wiring: a cheat sheet

Your home's electrical wiring is a crucial aspect of its safety and performance. The choice between aluminum and copper wiring has significant implications. Homes in Milton and elsewhere built in the 1960s and 1970s most likely had aluminum wiring installed.  Let's explore the key differences and when rewiring may be necessary.

Aluminum Wiring

Pros:

1. Cost-effective
2. Lightweight
3. Good conductivity

Cons:

1. Susceptible to corrosion
2. Expansion and contraction issues
3. Slightly higher fire risk

Copper Wiring

Pros:

1. Excellent conductivity
2. Durable and long-lasting
3. Heat-resistant

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Cons:

1. Higher cost
2. Heavier
3. Prone to theft

When to Consider Rewiring
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1. Homes with older aluminum wiring (1960s-1970s)
2. Signs of corrosion, overheating, or frequent electrical problems
3. During major renovations or additions
4. Insurance concerns or safety issues
5. Inadequate electrical capacity

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Example

At Milton Electric, we recently assisted a homeowner in upgrading their home’s electrical system by replacing aluminum wiring with safer, more reliable copper wiring. Many homes built in the 1960s and 1970s in Ontario used outdated aluminum wiring, which has been linked to higher risks of overheating and electrical fires if not properly maintained. Our team carefully rewired the home with copper, ensuring all connections met current safety standards and reducing the chances of future electrical hazards. Located just a short drive from Kelso Conservation Area, this project highlights our commitment to protecting Milton families by modernizing older electrical systems and bringing them up to today’s codes.

The results were immediate and positive for the homeowner. By switching to copper wiring, they now benefit from a safer, more efficient electrical system that can handle the power demands of modern appliances and technology. Copper is not only more durable but also provides better conductivity, which reduces energy waste and improves overall performance. The homeowner noticed their outlets and switches operating more reliably, and they gained peace of mind knowing their risk of electrical failure or fire had been greatly reduced. With electrical safety being a concern across Ontario—where the Electrical Safety Authority (ESA) reports aluminum wiring is present in thousands of older homes—projects like this ensure Milton residents can enjoy both safety and efficiency in their homes. 


Always hire a licensed electrician Milton locals need for rewiring projects to ensure safety and compliance with electrical codes. Choosing the right wiring material is essential for your home's long-term safety and efficiency.  You can also refer to ESA's guideline on aluminum wiring.

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