Knob-and-tube was standard wiring in American homes into the 1940s, and a surprising amount of it is still live in northern New Jersey. Replacing it is one of the larger jobs we do, and one of the most misunderstood.
Why it gets replaced
- Insurance. This is the most common trigger. Many carriers will not write or renew a policy on a home with active knob-and-tube, and some require a licensed electrician to certify it has been removed.
- No ground. Knob-and-tube has no equipment grounding conductor. Every outlet on it is two-prong, or has been illegally replaced with a three-prong that grounds nothing.
- Brittle insulation. The rubber and cloth insulation embrittles and falls away after decades, leaving bare conductor.
- Buried in insulation. Knob-and-tube was designed to dissipate heat into open air. Later blown-in attic insulation traps that heat. This is a genuine fire risk and a common finding.
- Capacity. It was installed for lighting and a couple of outlets per room, not modern loads.
Full or partial replacement
Not every home needs everything torn out at once. Many houses have had kitchens, baths and additions rewired over the years, leaving knob-and-tube only in original bedrooms and the attic run. Partial replacement targeting the remaining original circuits is often the sensible path, and it is considerably cheaper.
What matters for insurance is usually that no knob-and-tube remains energised. Abandoned wire left in a wall but disconnected at both ends is generally acceptable. We will document what was removed and what was made dead.
How disruptive is it
Honestly: it is disruptive. New cable has to reach every device, which means opening walls and ceilings at strategic points. How much depends on attic and basement access. A house with a full walk-up attic and an open basement can often be done with limited wall damage. A house with finished space above and below is harder.
We walk the house first, identify where access exists, and give you a realistic picture of the patching involved before you commit.
See knob-and-tube and home insurance in NJ and signs your home needs rewiring.
Who to call
Voltus Energy Solutions is a licensed and insured New Jersey electrical contractor based in Montclair, NJ license #34EI01906000. Call (973) 382-9995 or use our service request form.