If your home was built mid 1960's to late 1970's then it may have Aluminum Wiring. Aluminum Wiring is silver in
color as opposed to a brownish color for copper wire, see pictures below.
When Aluminum Wiring is found in a home, home inspectors are required to report on it...many insurers may
not provide or renew insurance coverage on these homes unless the wiring is inspected by the Electrical Safety
Authority (ESA), repaired or replaced as necessary, and a copy of the Certificate of Inspection is provided to
the insurer. You should check with your insurance company for their requirements.
Why is Aluminum Wiring an issue?
This is due to the tendency of aluminum wiring to oxidize (rust), and aluminum’s incompatibility with devices
designed for use with copper wiring only. Aluminum has a higher rate of expansion than copper wiring, which
can lead to loose connections, arcing and melting, eventually fire. Aluminum wiring should only be connected to
approved electrical devices.
Note: Warm cover plates or discolouration of switches or receptacles, flickering lights or the smell of hot plastic
insulation may be evidence of poor or improperly made connections.
How to resolve the issue of Aluminum Wiring:
A Licensed Electrician should be hired to throughly inspect the house. The Aluminum wiring and all electrical
outlet, switches and any fixture that the wiring is connected to must be approved for the use of aluminum wiring.
The licensed electrician may pig tail the wire, which is connecting a copper wire to the aluminum wire and then
connecting the other end of the copper wire to the screw terminal of the electrical fixture (see picture to the left
of this paragraph). And or the licensed electrician may also use a special paste to coat the aluminum wire so it
may reduce or slow down the oxidation process.
MUST READ THIS: Here is a News Flash 15-02-FL from the ESA (Electrical Safety Authority) which provides
information on Aluminum Wiring and the need for a "safety certificate".
Safety Issue: DO NOT open electrical panels or outlets, if your not sure call a Qualified Licensed
|Here you will see Aluminum wiring on
the left and Copper on the right
|Damage which can occur
when Aluminum wiring is not
installed correctly, and/or
when the wrong type of
Knob & Tube wiring:
Knob & Tube Wiring is typically found in Homes up to 1950's. It consisted of single insulated
copper conductors run within wall or ceiling cavities, passing through joist and stud drill-holes via
protective porcelain insulating tubes, and supported along their length on nailed-down porcelain
Where conductors entered a wiring device such as a lamp or switch, they were protected by
flexible cloth insulating sleeving. The first insulation was asphalt-saturated cotton cloth, then
rubber became common. Wire splices in such installations were twisted for good mechanical
strength, then soldered and wrapped with friction tape (asphalt saturated cloth), or made inside
metal junction boxes.
Why is Knob and Tube wiring an issue?
1. Knob-And-Tube wiring never included a safety grounding conductor.
2. It permitted the use of in-line splices in walls without a junction box (and thus exposing a
potential fire hazard of an uncontained spark caused by arcing following mechanical failure of the
splice). Especially a concern if a homeowner decided to install an additional outlet and tie it into
the old wiring.
3. Improper fuse ratings were used to compensate for the overtaxing of a circuit.
What to do if you suspect Knob and Tube wiring:
You should consult with your insurance company as to what their policy is. They may require a
licensed electrician further evaluate as to how many circuits there are and the condition of the
wiring. They may allow a percentage of knob and tube or they may require an upgrade to more
modern wiring. Always check with your insurance company as to what there specific policy is.
MUST READ THIS: Here is a News Flash 09-09-FL from the ESA (Electrical Safety Authority)
which provides information on Knob and Tube wiring.
Safety Issue: DO NOT touch or disturb Knob and Tube wiring, if your not sure call a
Qualified Licensed Electrician...
GFCI - A ground fault happens whenever electricity escapes the confines of the wiring in an
appliance, light fixture, or power tool and takes a shortcut to the ground. When that short cut is
through a human, the results can be deadly. About 200 people in the U.S. Alone die of ground
faults each year, accounting for two-thirds of all electrocutions occurring in homes.
To prevent such accidents, Charles Dalziel, a professor of electrical engineering at the
University of California, invented the ground-fault circuit interrupter (GFCI), in 1961. Most of the
time, his invention does nothing; it just monitors the difference in the current flowing into and out
of a tool or appliance. But when that difference exceeds 5 milliamps, an indication that a ground
fault may be occurring, the GFCI shuts off the flow in an instant — as little as .025 second.
Where are GFCI's Used?
GFCI's should be installed withing 3 feet (1.5 meters) of any water source such as - bathroom
and kitchen sinks, laundry tubs, whirlpools, jacuzzi's, exterior outlets such as garages,
swimming pools and spas. There is an Ontario Building Code Requirement for the placement
You may notice a home built after around 1986 may only have GFCI's at the bathroom sinks and
the reset button may actually be located inside the main electrical panel. Homes built after
around 2010 should also have GFCI's at the outlets near the Kitchen sinks and Laundry Tubs.
Homes that have been recently renovated should also have GFCI's installed at all outlets as
stated above and near Kitchen Sinks, Laundry Tubs and or any outlet withing 3 feet (1.5 meters)
of any water source.
Tip - If your renting out a home and or basement apartment then you may also want to make
sure you have GFCI's in all required locations - possible safety issue which may also lead to a
Final Note: GFCI's can be purchased at most hardware stores usually for approx $15-$40
depending on the type. I recommend that a QUALIFIED LICENSED ELECTRICIAN perform all
Why Test a GFCI?
GFCI's are a mechanical device which means that they can fail. Sometimes they may fail and
still provide power, other times they may not. GFCI's have two buttons on the face of the
receptical/outlet some may have blue and white or red and white or the same colours. One
button is actually a "test" button and they other is a "reset" button. It is recommended that ALL
GFCI's be tested just after installation and on a monthly basis for proper operation.
|Examples of knob & tube
Not sure how much electricity your using? And you don't really know where to start with the
math. Luckily there are programs out there that can do the math for you, all you need is to
plug in a few numbers.
HydroOne calculator is the Appliance Cost Calculator where you can pick an individual
appliance like an air cleaner or can opener or one of about 30-40 get the cost to operate the
HydroOne.com - Appliance Electricity Cost Calculator
Rapidtables.com - Electricity Bill Calculator
information, materials and techniques described are the responsibility of the user. Readers are advised to consult appropriate
professional resources to determine what is safe and suitable in their particular case. DASH Inspection Services assumes no
responsibility for any consequence arising from use of the information, materials and techniques described. Any reference to a
specific company is for general information only. I highly recommend you get a min of three quotes and do your homework.