Open an attic hatch or a basement ceiling in a Toronto or GTA home built before the 1960s and you might find wiring wrapped in a woven fabric jacket instead of the smooth plastic sheath on modern cable. That is cloth-covered wiring, and the honest answer on whether it is a fire hazard is: it depends entirely on its condition today, not on how it looked when installed. This guide covers what cloth wiring actually is, why it degrades, and when it crosses from vintage curiosity into genuine fire risk.
Cloth-covered wiring is early-to-mid 20th century electrical cable insulated with rubber and wrapped in a woven cotton or fabric braid instead of modern thermoplastic. It becomes a fire hazard once the rubber insulation underneath the cloth dries out, cracks, and crumbles — exposing bare copper that can arc or short against framing, nails, or itself. New cloth wiring in the 1930s–1950s was code-compliant and safe. Cloth wiring today, 70–100 years later, is a different story: the rubber compound has a finite chemical life and most of it has now outlived that life.
It is easy to confuse with knob-and-tube, which uses ceramic knobs and tubes with cloth-covered conductors running through open air rather than bundled cable. See what is knob and tube wiring for that specific system.
Related: can mice chewing wires cause a fire.
Do not touch or flex old cloth wiring to test it — disturbing brittle insulation can expose conductors that were otherwise contained. Photograph and call an ESA-licensed electrician instead.
Most major Ontario insurers treat cloth-covered wiring the same way they treat knob-and-tube: a red flag that either blocks a new policy outright or requires a licensed inspection report before binding coverage. If your home has cloth wiring and you have never disclosed it to your insurer, that is worth doing proactively — a claim denial after a fire is a far worse outcome than a premium adjustment now.
Not automatically. A licensed contractor inspection distinguishes between:
A partial rewire targeting only the cloth-wired circuits is often more affordable than a whole-house rewire. See how much does it cost to rewire a whole house.
The cloth wiring we see fail most dramatically in the GTA is not the wiring sitting quietly in an untouched attic — it is the section someone brushed against while running a new cable bundle nearby, or coiled aside during an insulation top-up. Cloth insulation that has survived 80 years intact can crumble the moment it is disturbed. If you know or suspect your home has cloth wiring, treat every attic and basement access point as a no-touch zone until a licensed contractor has assessed it, and budget for replacing at least the circuits still in active use.
No. Knob and tube uses ceramic supports with open-air conductors. Cloth wiring is bundled cable with a fabric-wrapped rubber jacket, though both are common in the same era of home.
Most cloth wiring in Ontario homes is now 65–95 years old, well past the expected chemical life of the rubber insulation underneath.
No. A new breaker does not repair degraded insulation on the conductor it protects.
Many Ontario insurers ask directly on older homes or require an inspection before binding or renewing coverage.
Only if a licensed contractor confirms it is fully disconnected at both ends and capped in an accessible box. See is it safe to leave abandoned wiring in a wall.
Found cloth-covered wiring in your Toronto or GTA home? Call ezsmart at 416-838-9006 or use our contact page. An ESA-licensed electrician will assess its condition and quote replacement where needed.
Electrician Since 2008 Journeyman Electrician Designated Master Electrician at EZSMART Corp