Aluminum wiring is safe when properly installed, but insurance companies aren’t keen on it. In buildings there are two types of aluminum wiring we typically come across: solid strand (pictured left above) and multi-strand (pictured right above).
Multi-strand is used today in certain applications, such as, 220-volt circuits for stoves, dryers and air conditioners. It’s also used on the main service entrance wires from the street to the house. When we talk about concerns with aluminium wiring, they arise with solid-strand wiring. For example, when solid-strand wiring is connected to devices (e.g. receptacles, light fixtures) which were not designed for aluminum, or, when aluminum and copper wires are attached together.
All electrical devices are rated to be used with copper, aluminium or both. So, if you have aluminum wiring, special care must be taken to ensure that connections made to these devices are suitable for this type of wiring. Further, where aluminum and copper wires are connected, proper paste / flux and wire connectors should be used.
Be sure to inform your insurance broker that your home has aluminum wiring as some companies no longer provide insurance coverage on homes with this wiring. If they do provide coverage, they may request further inspections from, the Electrical Safety Authority (ESA) and / or a licensed electrician.