As space in our city becomes limited, more and more people are choosing to buy older homes in more established neighborhoods. Please note that these homes although well built can have seriously dated electrical infrastructures.

Knob and tube
Knob and tube was the wiring that was placed in homes when homes were first electrified. Knob and tube was safe for its day but as more and more electrical devices were becoming standard in our homes, this system quickly became inadequate.
Some ways to tell if your home might have knob and tube are:

  1.  One outlet one switch and one light in a bedroom was standard
  2. Two prong outlets that do not have a hole for a ground
  3. At this time outlets would be mounted in baseboard

Below is a link to a bulletin put out by The Ontario Electrical Safety Authority (ESA) regarding Knob and Tube wire in homes.

First generation Romex
When they caught on in the late 40s to early 50s that the K & T was not working, romex was introduced. It was a huge improvement! At this time they started installing a second receptacle in rooms, doubling the amount of outlets in a house. Although this was a step in the right direction it would still not satisfy our needs in the future. First generation romex looks to be wrapped in cloth and is wide and narrow like a thick tape. It carries two conductors: a hot and a neutral. Sadly for the first few years they did not add a ground wire, so 2 prong outlets would still be used. Many home owners make the mistake of replacing a 2 prong outlet with a 3 prong outlet, this actually makes things pretty dangerous. Correct fix would be to add a gfci receptacle.

Aluminum wire
1960- late 1970s
This is not a good time for wiring. Approximately 450 000 homes were wired across Canada using aluminum wire. It was mostly used because it was cheaper than copper.
Below is a link to a bulletin put out by The Ontario Electrical Safety Authority (ESA) regarding aluminum wire in homes.


When entering into a renovation be sure to get advice from a licensed electrician. CanNam Electric would be more than happy to provide sound advice, a quote or a second opinion.