In short
- ESA dates knob-and-tube to the early 1900s through the 1940s; many insurers will not provide or renew coverage on a house that has it.
- ESA lets existing knob-and-tube stay on a 15 A fuse or breaker, with no added outlets and conductors in good visible condition.
- HomeStars puts a whole-home rewire at $8,000–$20,000 or more in Canada, plus $2,000–$5,000 when drywall is cut and patched.
- The Better Homes Ottawa loan covers wiring and panel upgrades required to permit energy improvements.
Typical prices in Ottawa
| Job | Typical range | Notes |
|---|---|---|
| Whole-home rewire | $8,000–$20,000+ | HomeStars, Canada-wide 2026 guide |
| Drywall restoration after a rewire | $2,000–$5,000 | HomeStars, Canada-wide |
| Extra hourly rate in a pre-1980s house with knob-and-tube or aluminum wiring | +$50–$150 per hour | HomeStars, Canada-wide |
| Replacement, bungalow 1,000–1,200 sq. ft. | $9,500–$15,000 | RenoQuotes planning estimate, Canada-wide, incl. finishing |
| Replacement, two-storey 1,500–2,000 sq. ft. | $14,500–$22,500 | Canadian renovation guide, incl. finishing |
| 200 A panel upgrade, if needed | $2,500–$4,500 | Canadian renovation guide, separate line |
| ESA notification, alterations, no service work | $46–$201 | ESA 2026 contractor rate, by outlet count |
Sources. HomeStars, Electrician Hourly Rate in Canada: 2026 Guide, updated 21.08.2026, seen 29.10.2026. Canadian planning estimates: RenoQuotes, Replacing Knob-and-Tube Wiring in Canada: How Much Does It Cost in 2026?, published 01.10.2026, seen 29.10.2026. ESA fees: 2026 Residential Fees, Quick Reference Guide, as of 01.04.2026, seen 29.10.2026. Rules: ESA, Knob and Tube Wiring, Flash 22-16-FL, Knob and tube wiring in residential installations (May 2022), Notifications and Inspections, Finding the Right Contractor, seen 29.10.2026. Insulation: Natural Resources Canada, Keeping the Heat In, Section 3, seen 29.10.2026. Loan: City of Ottawa, Better Homes Ottawa Loan Program, seen 29.10.2026. Insurance: MyChoice, A Guide to Knob and Tube Wiring and Insurance, seen 29.10.2026. Contracts: Ontario, guide for home renovation businesses, seen 29.10.2026. Neighbourhoods: Wikipedia, The Glebe, Hintonburg, Old Ottawa South, read 29.10.2026.
Reading your insurer’s conditions
ESA says many insurers will not provide or renew coverage on a house with this wiring, and some want it replaced first. An Ontario insurance comparison guide adds that some insurers consider coverage after a Licensed Electrical Contractor (LEC) inspects it, and some write a policy for a limited period while updates get done.
Read the letter for three things: assessment, partial work or full replacement; the documents it wants back; and the date. Quote all three in your request.
What ESA lets stay in the walls
ESA’s flash notice 22-16-FL lets existing knob-and-tube on lighting and outlet circuits remain when a 15 A fuse or breaker protects it, no outlets have been added that overload the circuit, and the conductors look sound where visible. ESA recommends an LEC check it and replace damaged, overheated or overloaded runs.
The notice also lists what turns up in these houses: 20 or 30 A fuses where 15 A belongs, extension cords used as permanent wiring, outlets tapped onto old circuits, and ground pins cut off plugs. Mention any of these in your request. Any change to the wiring needs a notification filed with ESA.
Glebe, Hintonburg, Old Ottawa South
ESA dates knob-and-tube to the early 1900s through the 1940s. Wikipedia describes Glebe houses as largely built before 1914, with many later split into rental apartments or rooming houses. South of Wellington, Hintonburg is almost entirely brick-veneer wood-frame houses from the 1910s and 1920s. Old Ottawa South grew as a streetcar suburb in the early 1900s, with many American Foursquare houses of the 1920s and 1930s, and many of them upgraded and added to over the years.
A house of that age with renovations or conversions can have old and newer wiring side by side. List every renovation you know of.
Assessment, partial replacement or full rewire
- Assessment. An LEC traces which circuits are still knob-and-tube and writes up their condition. ESA notes this differs from a home inspection: it covers only the electrical.
- Partial replacement. The live knob-and-tube circuits are replaced and newer circuits stay. Check first that your insurer accepts a partial scope.
- Full rewire. Every circuit is replaced; see whole-house rewiring for the full-house scope.
A rewire can push the panel past its limits; see panel upgrades.
Attic insulation and the Better Homes Ottawa loan
Natural Resources Canada warns that insulation should never touch old knob-and-tube wiring. Attic insulation is one of the measures the City’s Better Homes Ottawa loan pays for, and the same list includes wiring and panel upgrades required to permit energy improvements. The loan has a 20-year term at 4.33% fixed, with a $10,000 minimum, and only costs after the City’s Notice to Proceed count. If the rewire is part of an insulation project, say so in the request.
What moves the price and what the quote should list
HomeStars puts a whole-home rewire at $8,000–$20,000 or more, plus $2,000–$5,000 when drywall is cut and patched. Plaster walls, a second storey and finished ceilings add openings and labour. A Canadian renovation quote platform gives planning estimates of $9,500–$15,000 for a 1,000–1,200 sq. ft. bungalow and $14,500–$22,500 for a 1,500–2,000 sq. ft. two-storey house, drywall and finishing included. They are Canada-wide figures that the source itself calls planning estimates.
The quote should list the circuits replaced, how the old wiring is handled, wall openings and who closes them, any panel work, and the ESA fee: $46 for up to 10 outlets to $201 for 41 or more at the 2026 contractor rate. ESA inspects before walls close. In Ontario, home repair work over $50 needs a written agreement, and the final price can exceed the estimate by 10% at most.
Papers to keep
Keep the LEC’s written assessment with its ECRA/ESA licence number, the ESA notification number, the Certificate of Acceptance, which ESA says your contractor can provide for your insurer, and the insurer’s written confirmation. Buying a house with knob-and-tube? See electrical checks when buying.
Who you are dealing with
Ottawa Electric Desk passes your request to one independent local electrical contracting company. That company calls you back, scopes the knob-and-tube work and does it.
Questions to ask the company
- Which circuits still run on knob-and-tube, and how did you confirm which are live?
- Will your written assessment say what stays, what goes and why, for my insurer?
- Are wall and ceiling openings patched in your price, and who paints?
- What is your ECRA/ESA licence number, and is the ESA fee on the estimate?
- When does ESA inspect, and will the Certificate of Acceptance come to me?
Have this ready for the call
- The insurer's or lender's letter, with any deadline
- Year built, storeys, and plaster or drywall walls
- A photo of the fuse box or panel, door open, labels readable
- Photos of old wiring visible from the basement or attic hatch
- Work planned next: attic insulation, a kitchen, a basement
Questions people ask
Is knob-and-tube wiring illegal in Ontario?
The 2021 Ontario Electrical Safety Code deleted its installation rules, and ESA notes the Code applies going forward only. Existing wiring may stay on the conditions ESA sets. Your insurer can still set its own terms.
Will my home insurance pay for the rewire?
An Ontario insurance comparison guide says upgrading an old system is generally the owner’s cost, since home insurance covers losses and leaves maintenance to you. Ask the insurer to put its conditions in writing.
Can disconnected wiring stay inside the walls?
A Canadian renovation guide describes sealed-in wiring being disconnected from the panel, cut at the ends and left in place without power. The insurance guide warns against calling wiring inactive until a qualified electrical contractor has verified it.
Can two-prong outlets become three-prong?
ESA allows it with a bonding conductor to ground, or with Class A GFCI protection. GFCI gives no ground reference, so surge protective devices for computer and entertainment equipment will not function there. More on GFCI outlets.
We want blown-in insulation in the attic. Is that a problem?
Natural Resources Canada warns against letting insulation touch old knob-and-tube wiring because of the fire hazard. Book the electrical assessment before the insulation crew.
