Where the pre-1950 belt runs
Every city keeps its oldest wiring in its most charming postal codes, and the rewiring requests that reach Ottawa Panel Upgrades map the pattern precisely: the red-brick streets of the Glebe and Old Ottawa South, Centretown's converted singles, the pre-war blocks of Westboro, Hintonburg and Mechanicsville, Sandy Hill and New Edinburgh's embassy-adjacent homes, and Vanier's wartime stock. Homes built before roughly 1950 that were never fully rewired should be presumed to carry knob-and-tube until a licensed trace proves otherwise — including houses whose listings said "updated," which usually meant kitchens and bathrooms only.
The system itself: single copper conductors — hot and neutral run separately — strung through ceramic knobs and tubes, insulated in rubber and cloth, with no ground conductor anywhere. Competent engineering for the Laurier era. Three things have turned against it since:
- The insulation retrofit collision. K&T sheds heat into open air by design. Ottawa's decades of attic-insulation programs buried the runs in blown-in material, trapping heat around conductors whose rubber had already gone brittle. The efficiency upgrade and the fire risk were installed together.
- A century of amateur splices. Taped junctions in wall cavities, 1970s circuits tied onto 1920s loops, buried connections no inspector can see — the system's condition is unknowable without opening things up.
- No ground, no tolerance for modern loads. Two-prong receptacles, no path for fault current, and original services often sized at 60 amps for a house that now runs a modern kitchen.
The legal position — and the quiet trap in it
Ontario's electrical code does not order existing knob-and-tube removed. It does prohibit extending or modifying it. That distinction sounds academic until you renovate: the moment a wall opens for a kitchen, a bathroom or a basement project, the old wiring in that scope must be brought to current standard. Central Ottawa's renovation appetite means K&T rarely gets to die of old age — it gets discovered, mid-project, on a schedule nobody chose.
The insurer usually arrives before the renovator. Most standard carriers refuse new policies on homes with live knob-and-tube or renew only on condition of replacement — the mechanics of those letters, and how to buy time correctly, are on the insurance page. Buyers feel it hardest: financing needs insurance, insurance needs the rewire plan, and the closing date doesn't move. The buying & selling guide covers keeping a deal alive.
What an Ottawa rewire actually costs and involves
Published Ottawa figures for a typical 1,500–2,500 sq ft central home run $12,000–$22,000 for a complete rewire — new grounded circuits throughout, a 200-amp panel, ESA permit and inspection included. Per-circuit removal is published around $400–$800, and most homes carry 8–15 circuits, which is why partial jobs (replacing only what's still live) can land far below the full-rewire number. The work is fished through existing cavities from basement and attic through small patched openings — not the wall demolition homeowners fear — and the house stays livable throughout. Because the panel is replaced anyway, this is also the natural moment to resolve any flagged panel brand and right-size the service on the 200-amp question; the combined numbers sit on the cost page.
The deliverable that matters is the same as every project on this site: ESA inspects the finished work and issues the certificate that moves your file from "century home, uninsurable wiring" to "century home, rewired and certified" — a phrase that reads just as well in a listing as it does in a renewal.