Knob & Tube Rewiring — Toronto ESA-Permitted

Small bungalow (1,000–1,400 sq ft, partial K&T): $8,000–$12,000. Standard semi or small detached (1,500–2,000 sq ft, full K&T): $12,000–$18,000. Larger detached or 2.5-storey Edwardian (2,500–3,500 sq ft, full K&T): $18,000–$25,000+. Includes ESA-permitted rewiring, drywall/plaster repair, paint, baseboard replacement, fixture re-install, and ESA Form 1. Panel upgrade often pulled into scope: +$2,500–$5,500.

Most major Canadian insurers (Aviva, Intact, TD, Wawanesa, Co-operators, Economical) refuse to renew policies on properties with K&T circuits exceeding 10–15% of wiring inventory, and require full removal within 30–90 days of policy notice. The reason is documented failure-mode risk: 90–120-year-old rubber/cloth insulation degradation, connection oxidation, modern-appliance load mismatch, and rodent damage. ESA Form 1 (Certificate of Inspection) issued after rewiring satisfies the insurer.

ESA Form 1 is the Certificate of Inspection issued by the Electrical Safety Authority after passing final inspection of permit-pulled work. Insurers require this document as proof that the rewiring was done by ECRA-licensed personnel and inspected to Ontario Electrical Safety Code standards. RenoHouse delivers Form 1 plus a project-completion package within 5 business days of final inspection.

Some insurers accept partial removal (down to 0% active K&T) but most now require full removal of all active circuits — the 10–15% threshold has dropped to zero with several carriers in 2025–2026. Confirm with your insurer's underwriter before quoting partial scope. RenoHouse defaults to full-house rewiring because the partial-scope cost savings rarely exceed the cost of having to come back later for the rest.

A full-house K&T rewire requires 30–50 wall and ceiling openings (6"x10" to 12"x18" each) to route NMD-90 cable from outlet to junction to switch to fixture. In plaster homes (most pre-1950 Toronto stock) the patches are harder — cuts must respect lath spacing, patch material must bond to existing lath, and texture/finish must match. We default to skim-coating affected walls when more than 4 patches are needed in a single room. Drywall/plaster repair often costs more than the wiring itself on K&T jobs.

Yes — strongly recommended. Every drywall patch made for the rewiring becomes 'free' (already in the renovation scope), and the renovation timeline absorbs ESA inspection holds. Combined K&T rewiring + room renovation is 25–35% cheaper than rewiring done alone followed by a renovation 12 months later. We sequence both projects under one contract with one set of permits where possible.

Yes — RenoHouse holds Master Electrician licensing and an ECRA/ESA contractor license. All electrical work is performed under ECRA-licensed personnel, with ESA Permits pulled by the Master Electrician of record. Drywall/plaster repair, paint, baseboard, and finish work is performed by RenoHouse trades. The customer has one point of contact for the entire project.

Pre-1980 plaster walls in older Toronto homes may contain asbestos in the finish coat or joint compound. When wall openings exceed Type 1 thresholds (~1 m² per opening), we coordinate with HCRA-licensed Type 1/2 abatement specialists before continuing rough-in. Asbestos abatement is performed by certified specialist (we do NOT remove asbestos in-house) — see our Asbestos Abatement Coordination page.

Smaller homes (1,000–1,400 sq ft): 5–8 business days for rough-in + drywall/plaster repair, plus 3–5 days for paint and finish. Standard semi or small detached: 8–12 business days. Larger detached or 2.5-storey Edwardian: 12–18 business days. ESA inspections (rough-in and final) add 2–5 business days each in scheduling. Total project clock: 3–6 weeks from contract to ESA Form 1, depending on scope and inspector availability.

Most homeowners stay in place during smaller-scope rewires — work proceeds room-by-room with electrical supply maintained on rotating circuits. Larger full-house rewires sometimes benefit from 1–2 weeks of vacancy during rough-in if the homeowner has elderly residents, infants, or asthma sensitivity to plaster dust. We discuss case-by-case at the site visit. Power is never fully cut for more than 4–8 hours at a time.