Do I need to replace knob-and-tube wiring for a kitchen reno in NB?

Yes, knob-and-tube wiring must be replaced in any area affected by a kitchen renovation in New Brunswick — it cannot remain in walls where new insulation is being added, and it does not meet current NB Building Code requirements for kitchen circuits. While you are not legally required to rewire your entire house, any circuits being modified, extended, or in areas where walls are opened during the renovation must be brought up to current code.

Knob-and-tube (K&T) wiring was standard in NB homes built before 1950 and is occasionally found in homes built as late as the early 1960s. It consists of individual wires run through ceramic knobs and tubes — there is no ground wire, no modern insulation rating, and the circuits are not designed for today's kitchen loads. Modern kitchen code requires grounded circuits, GFCI protection, and dedicated 20-amp small appliance circuits — none of which are possible with knob-and-tube wiring.

Why K&T Is Incompatible with Kitchen Renovations

The most critical issue is insulation contact. Knob-and-tube wiring was designed to dissipate heat into open air within wall and ceiling cavities. When insulation — whether blown-in, batt, or spray foam — contacts K&T wiring, the heat cannot escape and the fire risk increases significantly. During a kitchen renovation, if you are opening walls to run new plumbing, add electrical circuits, or improve insulation, any K&T wiring in those walls must come out. An electrical inspector will flag it, and your renovation will not pass inspection if K&T remains in contact with insulation.

Beyond the code requirements, there are practical reasons to replace K&T during a kitchen renovation. The wiring is 60 to 100+ years old, and the cloth insulation on the conductors becomes brittle and cracks over time, exposing bare copper. The connections at junction points can loosen with age. And because there is no ground wire, you cannot install grounded outlets — which means no GFCI protection at countertop locations as required by current code.

The cost to replace knob-and-tube wiring in the kitchen area typically runs $3,000 to $8,000 in New Brunswick, depending on the size of the kitchen, accessibility of the wall and ceiling cavities, and how many circuits need to be run. This includes removing the old K&T, running new NMD90 (Romex) cable with proper grounding, installing new outlets and switches, and connecting everything to a modern panel. If your panel also needs upgrading from 60 amps — which is almost always the case in a K&T home — add $1,500 to $2,500 for the panel upgrade.

This work requires an electrical permit from your local municipality or Regional Service Commission, and both a rough-in inspection (before walls are closed) and a final inspection are mandatory. Your electrician handles the permit application, but make sure they provide you with the permit number and inspection results.

The silver lining is that a kitchen renovation is the most cost-effective time to deal with K&T wiring. The walls are already being opened, the electrician is already on site for new kitchen circuits, and the incremental cost of removing K&T while everything is accessible is far less than doing it as a standalone project later. If you are renovating a kitchen in an older NB home — particularly in the heritage neighbourhoods of Fredericton, Saint John, or Moncton — ask your electrician to assess the entire kitchen area for K&T during the initial site visit so the full scope and cost are clear before work begins.

---

Looking for experienced contractors? The New Brunswick Construction Network connects homeowners with qualified professionals:

• Gionetterenovations
• Thirty Four Renovations