Toronto Knob and Tube Wiring Replacement, Inspection, Repair

Knob and Tube Rewiring in Toronto

by Licensed Electrical Contractor

For Better, Safer Homes!

We specialize in low cost, fast, efficient & professional house rewiring

drastically cur your home insurance policy payments
make your home more comfortable and safe
greatly reduce the risk of fire & shock
give yourself a peace of mind

We also perform:

Knob and tube certified inspection report requested by your insurance broker
Home seller, avoid unpleasant surprises or drastic price reductions
Good Inspection Report is a great selling tool for sellers


Knob and Tube is an old two wire system where lights, plugs and receptacles are not grounded.

From 1880's it was widely used through the 1930's. In some locations installed into the late 1950's. Years ago there were few electrical appliances, electricity usage and loads were limited. K&T was the best and only option.

The conductors were spliced and soldered together inside walls, without junction boxes, and then wrapped with electrical tape. Wiring was rubber and cloth covered #14 copper supported by ceramic knobs nailed to the wood structure. When required to pass through the wood, ceramic tubes were inserted in holes to let conductors through. Therefore they never touched the wood structure or plaster. Heat from load or overload A/C current dissipated in the air space between rafters and partitions. These circuits originally could be protected by 20 Amp plug fuses. Do not use fuses or breakers over 15 Amp today. Over-fusing any 14 gauge line with 20 Amp or more is dangerous.

Visual inspection of conductors and splices can determine state of Knob and Tube integrity nowadays. Conductors with bare or dry, crumbling or stiff insulation should be replaced. These conditions resulted from over-current, shorts, improper fusing, high temperatures or natural aging. Problems are usually found in switch, plug, and junction boxes, in attics, furnace or boiler rooms and especially above the lights.

Splicing new cables with old ones is not a good idea. Avoid K&T circuit extensions and additional loads. The number of lights or receptacle on a 15 Amp circuit should be no more than 12.

When correctly suspended in the air it could carry higher current without overheating. It's a single advantage over the contemporary system.

The old system, on its own, is not inherently a problem. Wiring that has deteriorated or been abused is.

The ancient technique introduced more than 120 years ago at the dawn of electrification does not belong to a 21-century home. So take a deep breath and just get rid off it. That's the best and the safest step you could take.

In addition, generations of handymen and previous unskilled owners have been abusing your home wiring for decades. Inspection is indispensable for older than 50 year old homes. Together we could bring your house up to code and make your home really safe!

Call us if you do not know what to do, or if you are not sure about the condition of your system.

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