How to Remove Old Knob and Tube Wiring

How to Remove Old Knob and Tube Wiring


Knob and tube wiring was commonly installed in homes built before 1950. It consists of individual hot and neutral wires that are separated from each other, unlike modern Romex wiring that has the hot and neutral wires wrapped together in a plastic sheath. While knob and tube wiring was safe when it was installed correctly, it can become hazardous over time as insulation breaks down and connections come loose. Replacing knob and tube wiring with modern wiring improves safety and allows your home's electrical system to meet current code requirements. This article provides a step-by-step guide to safely removing old knob and tube wiring from your home.

Dangers of Knob and Tube Wiring

Knob and tube wiring poses several potential risks:

Replacing knob and tube wiring eliminates these serious hazards in your home's electrical system.

Preparing for the Project

Removing knob and tube wiring is an extensive project that requires proper planning and preparation:

Safety Gear

Tools Needed

Electrical Permits

Hire an Electrician

Removing Knob and Tube Wiring

With the right planning and safety preparations, you're ready to start eliminating the old, dangerous knob and tube wiring:

Turn Off Power and Verify

The first step is to switch off the main breaker to kill power to all wiring in the house. Use a voltage tester to double check that power is off before touching any wires.

Remove Fixtures and Outlets

Start by taking out light fixtures, outlets, switches and any other components wired to the old system. This gives access to junction points where you can cut the knob and tube wiring free.

Attics and Crawlspaces

These unfinished spaces often contain major portions of knob and tube wiring. Remove any insulation to access the wiring paths. Carefully remove staples, clips, and other fasteners holding the wiring in place.

Inside Walls

Drill holes or cut access panels in walls and ceilings to reach wiring runs. Pull out staples, remove fasteners, and detach wires where they enter and exit junction boxes.

Junction Boxes

Open up junction boxes throughout the home and use wire cutters to disconnect the old wiring from any modern wiring terminations. Cap these modern wires so they are isolated.

Fully Remove Wiring

Keep tracing wiring runs throughout the house, detaching the old knob and tube wires at every point. Coil up and dispose of the removed wiring until none remains within the home.

Patching and Repair

Once all knob and tube wiring is eliminated, patch holes in walls and ceilings with spackle. Repair any other cosmetic damage left from gaining access to wiring runs.

Replacing With New Wiring

With the old wiring completely removed, the final stage is replacing it with new, modern wiring:

Removing old knob and tube wiring is labor intensive, but essential for making a home safer. Once this outdated and hazardous wiring is fully eliminated and replaced, you can rest easy knowing your home's electrical system is safer and meets modern standards. With proper precautions, preparation, and help from an electrician, rid your home of old knob and tube wiring.