Aluminum & Knob-and-Tube Wiring Services

Aluminum branch-circuit wiring was installed in many Toronto and GTA homes built in the late 1960s and 1970s. The wire itself is not the problem — the connections are. Aluminum expands, contracts and oxidizes differently than copper, so terminations at receptacles, switches, splices and panel lugs loosen and heat over time.

Aluminum wiring work is remediation work: inspect every accessible connection, correct what is failing, and use devices and methods rated for aluminum. A full rewire is rarely necessary.

Knob-and-tube is a different situation entirely. It is the original wiring in many pre-1950 Toronto homes: two separate conductors run through porcelain tubes and supported on knobs, with no bonding conductor and rubber-and-cloth insulation that is now decades past its service life. There is no way to remediate the connections and keep it — knob-and-tube is replaced, not repaired.

The first step is identification. Many homes have partial knob-and-tube: some circuits were replaced during past renovations and others were simply abandoned in place, spliced into, or buried under blown-in insulation, which is a specific hazard because the conductors were designed to shed heat into open air.

Removal and rewiring is the permanent resolution: new grounded circuits fished through existing wall and ceiling cavities wherever possible, new devices and boxes, abandoned knob-and-tube taken out rather than left in place, and the panel updated to carry the new circuits. Renovations are the ideal time to do it, since walls and ceilings are already open. Where a home is occupied and finished, we phase the work circuit by circuit and open drywall only where it is genuinely necessary.