Knob & Tube
in Toronto

Knob-and-tube (K&T) wiring was the standard electrical wiring method in Ontario homes built before 1950. It uses ceramic knobs to support wires along joists and tubes to protect wires passing through wood framing. While revolutionary for its era, K&T wiring was designed for a time when homes had far fewer electrical demands. It has no ground wire, cannot handle modern electrical loads, and its cloth insulation degrades over decades.

Most Ontario insurance companies now require knob-and-tube wiring to be replaced as a condition of coverage. If you are buying a home with K&T wiring, your home inspector will flag it, and your insurer may refuse coverage or charge significantly higher premiums until it is replaced. Beyond insurance, K&T wiring is a genuine safety concern: degraded insulation creates fire risk, lack of grounding creates shock risk, and the inability to handle modern loads causes overheating.

Step 1: Complete inspection. We trace all K&T wiring throughout the home, including hidden runs in walls and ceilings. Step 2: Detailed scope and quote. We identify exactly what needs to be replaced and provide an honest assessment. Step 3: Methodical replacement. We remove the old K&T wiring and install modern NMD90 copper wiring with proper grounding. Step 4: ESA inspection and certification. Step 5: We provide all documentation your insurance company needs to update your policy.

Knob-and-tube replacement is one of the more involved electrical projects. Depending on your home, we may need to open sections of walls and ceilings to access the old wiring. We minimize disruption as much as possible, work room by room, and clean up daily. For a typical Brampton bungalow, the project takes 3-5 days. Two-storey homes may take 5-7 days. We coordinate with drywall contractors if patching is needed.

A homeowner in Brampton's downtown core purchased a 1941 two-storey home and their insurer refused to bind coverage until the K&T was fully replaced. We completed a room-by-room assessment, identified three partial K&T circuits still active on the second floor and two in the basement, and replaced all of them over four days. The homeowner had their certificate of inspection in hand within a week of calling us. In Mississauga's Port Credit neighbourhood, a homeowner discovered active knob-and-tube during a renovation when their contractor opened the kitchen ceiling. The kitchen had been partially updated but original K&T still fed the back bedroom circuits. We removed the remaining active K&T, ran new NMD90 throughout, and let the renovation continue on schedule. A couple in Caledon was selling their 1948 farmhouse and needed K&T removal as a condition of the buyer's financing. We prioritized their job, completed the replacement in five days, and had the ESA certificate delivered to their real estate lawyer before the scheduled closing. A Brampton homeowner on Vodden Street had a home that a previous electrician had partially updated - some circuits were new copper, others were old K&T. The mixing of systems was creating problems with tripping breakers. We traced all circuits, separated the old from the new, replaced the remaining K&T sections, and left the panel with properly identified circuits for the first time in decades.

In the past few years, Ontario home insurance companies have become significantly stricter about knob-and-tube wiring. Where many insurers previously required a letter from an electrician confirming the K&T was in acceptable condition, most now require full removal as a condition of coverage - no exceptions. There are a few reasons for this shift. First, Ontario homes with K&T are now 70 to 100+ years old, and even well-preserved K&T wiring is deteriorating. The cloth insulation becomes brittle and cracks over time. Second, insurance claim data connects older wiring types to a higher incidence of electrical fires. Third, the reinsurance market - the companies that insure the insurance companies - has pushed carriers to tighten standards. What this means practically: if you are buying a home with active K&T wiring, expect your insurer to either refuse coverage, issue coverage with a short compliance window (60 to 90 days), or charge a significant premium surcharge. Some insurers will not bind coverage at all until a licensed electrician confirms the K&T has been removed. We work with several real estate lawyers and agents in Brampton and Mississauga who refer clients to us specifically for pre-sale and pre-purchase K&T assessments. If you are buying or selling a home with K&T, call (647) 872-9954 and we can usually get an assessment scheduled quickly.