Knob-and-Tube and Aluminum Wiring Replacement Cost in Toronto

Knob-and-tube and aluminum wiring get talked about together, but they are two different problems with two very different price tags. Getting that distinction right is usually what saves the money.

For the service itself, see Aluminum & Knob-and-Tube Wiring Services.

Aluminum wiring: remediation, not replacement

Aluminum branch wiring was used in many GTA homes built in the late 1960s and 1970s. The wire is not the hazard — the connections are. Aluminum expands, contracts and oxidizes differently than copper, so terminations at outlets, switches, splices and panel lugs loosen and heat up over time.

The usual fix is copper pigtailing with approved connectors and CO/ALR-rated devices, plus corrections at the panel. It is priced by the number of devices and connections, not by the size of the house, and it costs a fraction of a full rewire. Most insurers accept it with ESA documentation.

Knob-and-tube: replacement only

Knob-and-tube is the original wiring in many pre-1950 Toronto homes: two separate conductors, no bonding conductor, and rubber-and-cloth insulation decades past its service life. There is no way to remediate it and keep it — it is replaced.

Price depends on how much of it is still live. Many homes have only a handful of active knob-and-tube circuits because past renovations replaced the rest, so a partial rewire does the job. Where it runs throughout, you are into a whole-home rewire — see whole-home rewiring cost in Toronto.

What changes the number

• How many circuits are still live versus abandoned in place
• Access: open renovation walls versus finished plaster in an occupied home
• Whether the panel or service must be upgraded as part of the work — a 100 amp to 200 amp upgrade is **$3,500 to $5,000+**, and a fuse box to breaker conversion is **$2,500 to $3,500**
• Knob-and-tube buried under blown-in insulation, which is a specific hazard because those conductors were designed to shed heat into open air
• Drywall and plaster patching afterwards

What your insurer actually wants

Insurers do not usually demand a specific method — they want documented, code-compliant remediation by a licensed contractor. That means the ESA permit pulled under our ECRA/ESA licence, the work inspected, and the ESA certificate issued. That certificate is what gets a policy renewed or written.

The honest summary

Aluminum wiring is often an affordable remediation. Knob-and-tube is a replacement job whose price depends almost entirely on how much is still live. We assess first and quote the least invasive option that passes inspection and satisfies your insurer.