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Knob-and-Tube Wiring Removed

No knob-and-tube wiring remains active in the home.

Spec

No knob-and-tube wiring remains active in the home.

Applies uniformly from Certified upward.

Scope

Knob-and-tube electrical wiring in existing dwellings (common in U.S. homes built 1880-1940).

Requirements

  1. 01.

    A licensed electrician must inspect the home for active knob-and-tube (K&T) wiring.

  2. 02.

    Any active K&T wiring must be replaced with modern grounded wiring before certification.

  3. 03.

    Inactive (disconnected) K&T may remain in place if confirmed by the electrician to be permanently disconnected from the panel.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Electrician's inspection report confirming presence/absence of active K&T.

  2. 02.

    For replacement work: electrical permit + final inspection sign-off.

Guidance

Why K&T is dangerous in a modern home

K&T wiring was rated for the loads of 1900-1940 (lights, irons, the occasional radio). It has no ground conductor, deteriorates over decades, and was never designed to operate in contact with insulation. Modern homes overload K&T circuits and trap heat in insulation around the wires — leading fire risk in pre-1940 housing stock.

Note

Insurance carriers increasingly refuse coverage or charge punitive premiums on homes with active K&T. Replacement during a renovation typically runs $5,000-$15,000 depending on access. It pays for itself in insurance savings and home value within a few years.