Aluminum wiring came out in the late 1960's and was used to mid 1970's.
Is there anything wrong with Aluminum wiring?
Whereas aluminum wiring is softer and lighter to use than copper and has less conductivity, this was combatted
by use of larger wiring gauge sizes. Where you would use a gauge 14 copper wire for a typical residential general
usage circuit, you would use a gauge 12 aluminum wire for the same circuit, both would be protected by a 15 amp fuse or breaker.
The one major problem with aluminum wiring is oxidation, which causes a breakdown in conductivity as soon
as the aluminum wiring has been stripped of its plastic covering. This is combatted by connecting the aluminum wiring
only to switches and receptacles with a Co/ALR rating, these devices were made specifically for aluminum conductors.
Where two aluminum wires are to be connected together or aluminum and copper wires are to be connected together
there is a special procedure and materials used. This includes lightly sanding of the wires, the use of an anti-oxident
cream or paste, then twisting the connectors together and installing a twist on connector approved for aluminum wiring.
The addition of copper "pigtails" spliced onto aluminum wires as described above will allow the use of standard
switches and receptacles, but one has to make sure that the extra wires and connectors do not exceed the fill permitted for
the outlet box, which could in turn cause overheating.
These conditions for aluminum wiring are covered under rule #12-118 of the Ontario Electrical Safety Code.
Did You Know?
All the city wiring that runs down your streets and up to your home are aluminum, and that all new breaker
panels and the breakers in them are manufactured to accommodate both copper and aluminum wiring.