Knob and Tube Wiring Replacement in Scarborough
KV Bear Electrical is a licensed electrical contractor (ECRA/ESA 7014730) based in Oshawa, serving homeowners in Scarborough. This page covers how our knob & tube wiring service works for Scarborough homes.
Get a Knob & Tube Wiring Quote in Scarborough
Knob and tube is a smaller issue in Scarborough than across Toronto as a whole, and the census shows why. ESA says the system was used in homes from the early 1900s to the 1940s. In the Scarborough Community Council area, only about a fifth of today's homes were built in 1960 or before, against nearly three in ten citywide, so most Scarborough houses were built after knob and tube had gone out of use.
That does not mean it never turns up. Pre-war houses and the older pockets of Scarborough are where it can still appear, sometimes hidden behind decades of later renovation. The Scarborough Southwest ward stands out, with four in ten homes built in 1960 or before, while the Scarborough-Rouge Park ward has very few. If you are buying, insuring or renovating one of the older houses, it is worth confirming what is actually in the walls rather than guessing from the year of construction.
What Scarborough Homeowners Should Know
The Electrical Safety Authority advises homeowners with knob and tube wiring to have a Licensed Electrical Contractor assess the system, which is separate from a home inspection, and to replace conductors that show mechanical damage, deterioration, poor connections, overheating or alterations made because of overloading. ESA states that knob and tube is safe when a Licensed Electrical Contractor properly maintains it.
Source: Knob and Tube Wiring, Electrical Safety Authority (esasafe.com)ESA says knob and tube wiring was used in homes from the early 1900s to the 1940s. The 2021 Ontario Electrical Safety Code removed the installation rules for knob and tube, but the code is not retroactive.
Source: Knob and Tube Wiring, Electrical Safety Authority (esasafe.com)Across the Scarborough Community Council area (Wards 20 to 25), the City of Toronto's 2021 profile shows 22.1% of 218,920 private dwellings were built in 1960 or before, against 29.3% for the whole city.
Source: Community Council Area Profile: Scarborough (2021 Census), City of Toronto (toronto.ca)The City's 2021 ward profile for Scarborough Southwest counts 16,845 private dwellings (40.2%) built in 1960 or before, compared with 29.3% city-wide.
Source: Ward Profile: Scarborough Southwest (2021 Census), City of Toronto (toronto.ca)In the Scarborough-Rouge Park ward, only 8.3% of private dwellings were built in 1960 or earlier, according to the City's 2021 ward profile, compared with 29.3% across Toronto.
Source: Ward Profile: Scarborough-Rouge Park (2021 Census), City of Toronto (toronto.ca)Toronto Hydro reminds customers that completed electrical work must pass an ESA inspection confirming it meets the Code, and that after a passed inspection ESA authorizes Toronto Hydro to energize, or re-energize, the service.
Source: Electrical safety at home, Toronto Hydro (torontohydro.com)
Facts checked October 13, 2026.
Where Knob and Tube Can Still Turn Up in Scarborough
Where it is exposed, knob and tube is easy to recognize: single insulated conductors run separately on porcelain knobs along the framing, with porcelain tubes where they pass through joists. In a finished house it is usually hidden. The clues are two-prong receptacles, cloth-covered wire at older fixtures, or a small sub-panel feeding a handful of old circuits.
In Scarborough the likeliest candidates are houses that predate the 1950s and older homes that were extended over the years, where a newer panel and new circuits can sit beside a few original runs to upstairs rooms or the attic. Houses from the 1960s and 1970s are far more likely to have copper or aluminum branch wiring than knob and tube, so an assessment of those homes usually focuses on other questions.
Knob and Tube Replacement or Removal: What the Work Involves
Knob and tube replacement means running new grounded copper circuits to every outlet the old wiring fed, then disconnecting the original conductors so they can never carry power again. Complete knob and tube removal, pulling the old wire out entirely, is done where it can be reached, in attics, basements and open walls. Elsewhere the old conductors are cut back and left dead in place.
The work is planned room by room to keep openings in plaster to a minimum, using attics, basements and closets as routes. Partial jobs are possible when only a few circuits remain. Our published range for full knob and tube removal in a typical Ontario home is $8,000 to $20,000 or more, with partial jobs typically at the lower end, and the itemized quote follows the assessment.
Permits, Insurance and Next Steps
Rewiring is carried out under an ESA notification filed by the Licensed Electrical Contractor before work begins. ESA inspects the new wiring at rough-in, before walls are closed, and again at completion. If the service equipment is changed during the job, Toronto Hydro restores power only after ESA has authorized it. The ESA Certificate of Acceptance at the end is the record ESA calls important for insurance and resale.
ESA notes that many insurers will not provide or renew coverage for homes with knob and tube, because they treat it as a higher risk. If an insurer or a home inspection has flagged it, begin with an assessment so you know whether you are dealing with a few circuits or the whole house. To arrange one for your Scarborough home, call 905-999-5048 or request a quote below.
Knob & Tube Wiring in Scarborough: Common Questions
Is knob and tube wiring common in Scarborough homes?
It is less common than across Toronto as a whole. ESA dates the system to homes from the early 1900s to the 1940s, and the City's 2021 figures show only 22.1% of Scarborough's homes were built in 1960 or before. It is most likely in pre-war houses and older pockets, not in the 1960s and 1970s housing that makes up so much of Scarborough.
My Scarborough house was built in the 1950s. Could it still have knob and tube?
It is unlikely to have been installed new then, since ESA places knob and tube in homes from the early 1900s to the 1940s. A 1950s house is still worth checking if it was built onto an older structure or has had undocumented electrical work. A look at the panel and a sample of outlets settles it quickly.
Do I have to remove knob and tube before selling my Scarborough home?
ESA does not say it must come out for a sale. It says the system is safe when a Licensed Electrical Contractor properly maintains it, and the 2021 code change is not retroactive. In practice, a buyer's insurer may refuse coverage or set conditions, which can affect the deal, so an assessment and any needed replacement before listing avoids surprises.
Can I keep some knob and tube circuits in my Scarborough house?
Possibly. ESA's position is that knob and tube is safe when properly maintained, with damaged, deteriorated or overloaded sections replaced. Whether keeping some circuits is practical depends on their condition and on your insurer, since ESA notes that many insurers will not provide or renew coverage on homes with this type of wiring.
What Our Customers Are Saying
“Kyle was extremely courteous, professional and friendly. He did a commendable job and even gave me a tip for a tripping issue without even having to look at it. He knows what he is doing. Would be my go to guy for anything electrical.”
“The entire process from quotation through contracting and performance of the work by Kyle was completed professionally and without any issues. The panel upgrade and EV charger installations are clean and neat and it is evident that Kyle takes pride in the quality of his work. Upon completion of the installations, Kyle ensured that the work site was 100% cleaned up.”
“KV Bear was recommended to us by a friend. We wanted to install a Tesla charger only to find out our electrical panel was known for faulting resulting in an electrical fire. He showed us signs of the panel arcing. The work was clean, professional, and fast! We are so happy we hired a professional.”
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