Skip to content
Aluminum wiring

An All-in Guide to Aluminum Wiring in Ontario

While aluminum wiring was once extensively used in residential construction due to its cost-effectiveness, it has gained a reputation for being a potential safety hazard.

This guide aims to provide you with everything an Ontario homeowner needs to know about aluminum wiring. Don't worry – this guide is here to empower you with knowledge, not to scare you. We'll explore the basics of aluminum wiring, including its history, safety, inspection passibility, home insurance concerns, improvement options, and things to watch as your home ages.

How to identify aluminum wiring in your home

Aluminum wiring is easy to identify. One of the quickest ways to discover what kind of wiring your home has is by heading to your basement. You can look at your electrical panel or along the ceiling where the wiring and plumbing run. Look along the casing of the wire, and you will see it labelled quite clearly. It should say aluminum or AL. Alternatively, copper wiring is typically marked as copper or CU.

There should be no exposed wires around your home. However, if there were, you'd also see the internal metal part of the wire as more of a silver colour than the orangey-reddish colour of copper. 

When was aluminum wiring used in Ontario?

Aluminum wiring was used throughout the 1960s and 1970s as an alternative to copper wiring. It is a much more affordable material than copper and is perfectly functional to run electrical systems in your home. Parts of the construction industry still use aluminum wiring because of the cheaper cost.

Aluminum wiring labelled AL

It is important to know that extra care is needed when using aluminum wiring. The biggest area of concern happens at the ends of the wires, also known as termination points, where the wire connects to a receptacle, like an outlet or switch. Exposed aluminum wire oxidizes, creating heat and impeding the flow of electricity. Fortunately, this can be prevented with oxide-inhibiting compounds and quality electrical work.

Aluminum also has different connective properties than copper, so it must connect to "CO/ALR" rated receptacles. These receptacles are designed to function with copper or aluminum terminations.

Lastly, you can mitigate the risks of aluminum wiring by using "pigtails." Pigtails are pieces of copper twisted and capped to the ends of the aluminum wire running through your home. This allows your house to have all copper terminations and receptacles while saving money using aluminum wiring throughout the rest of the home. 

Will aluminum wiring pass inspection?

Aluminum wiring can pass safety inspection. The Electrical Safety Authority of Ontario inspects all Ontario electrical work. It states, "The Ontario Electrical Safety Code (OESC) permits the installation of aluminum wiring." In an inspection, the ESA is looking for properly installed aluminum wiring. If it meets OESC guidelines, it will be approved.

Copper /aluminum receptacle example

Can you get home insurance in Ontario with aluminum wiring?

Yes, you can, but your approval rate with aluminum wiring will vary, depending on your insurance company. Here are a few steps you can take to get approval:

  1. Shop around. There are many different companies, and they will provide unique coverage at different rates.
  2. Get a professional electrical inspection. Showing professional approval of your electrical system can improve your odds of being approved for a policy.
  3. You can upgrade or replace your electrical wiring. See the following section.
  4. Document every action to prove to the insurance companies that you have done your due diligence.

Cost to replace aluminum wiring in an Ontario house 

With aluminum wiring, you have two options:

Option 1: Aluminum wiring replacement

This extensive job requires replacing all wiring and receptacles in the home. The cost to replace aluminum wiring in your home can vary widely depending on the size and complexity of your home. Rewiring a house requires a lot of material and labour and can cost between $10,000-$20,000.

Option 2: Wire remediation

This process uses pigtailing, as mentioned above, so all termination points and receptacles are copper and copper-rated. The aluminum wiring throughout the home remains in place. This process can cost between $2,000-$4,000.

It's best to hire a licensed electrical contractor to work with the aluminum wiring because the ESA mandates it, and it is your safest option. Improper work can create a handful of safety concerns. Mistakes are costly and could lead to fires or electrical dangers for you and your home. So, it's safer to have an expert handle it.

If you have work to complete with aluminum wiring in your home in Southwest Ontario, we're happy to help. We have served homeowners throughout the Niagara and Hamilton regions. To get in touch, please connect with us at 1-844-667-6937,, or by completing the form below. We offer free quotes on electrical projects and are happy to answer any further aluminum wiring questions.

Let's start a job together.

Serving the Hamilton and Niagara area.