A reader wrote to me that it was extremely difficult for him to insure his home, whose electrical wiring is made of aluminum. Why?
From 1960 to 1980, aluminum wiring was very popular because it is cheaper than copper, lighter, and more malleable.
However, after 30–40 years aluminum tends to oxidize, especially when it comes into contact with other materials (galvanic corrosion), for example with a steel junction box or a connector not certified for aluminum. Aluminum wiring is subject to thermal expansion and is more brittle than copper. Even if the wires themselves are safe, it is the connections that create problems. They can loosen, which can lead to short circuits and electrical arcing—and therefore fires.
Sometimes problems arise because of non-certified equipment connected to aluminum wiring.
Insurance difficulties
Insurance companies that offer home insurance do not like aluminum wiring. Some refuse to insure such properties at all. Others, such as Desjardins or Intact, are willing to insure homes with aluminum wiring, but they review each case individually.
They often require certain work to be done, such as installing special transition connectors that connect aluminum to copper to avoid corrosion.
Intact says it may require a certificate of compliance issued by an electrician and valid for less than 12 months. The insurer recommends going through a broker to obtain the most suitable coverage.
Scope of work
If your home has aluminum wiring, you have two options: replace all connections in the house or completely rewire it. This work must be performed by a certified electrician.
In the first option, the electrician can tighten and clean all connections in the house, apply anti-oxidation paste, and replace outlets and switches with models compatible with aluminum. Budget: about $4,000.
If a full rewiring is required, it is about $12,000–$20,000 depending on the complexity of the work and whether the electrical panel needs to be replaced.
Don’t forget to send a copy of the electrician’s invoice to the insurer: this may reduce the insurance premium (by several tens or even hundreds of dollars).
Tips
How can you recognize aluminum wiring? The current-carrying conductor is usually silvery in color, whereas copper wire has a… copper hue. The cable’s protective sheath is marked “AL”. Sometimes signs of a problem also include outlets that stop working, circuit breakers that trip for no apparent reason, flickering lights, heating of switch or outlet faceplates, and a burning smell near the electrical panel.
Building inspectors check whether a home’s wiring is made of aluminum and warn buyers about it.
Replacing wiring involves opening up the walls in all rooms. The work can take several days and will require plastering, painting, and cleanup. Budget an additional few hundred or even a few thousand dollars.
