How to Remove Old Knob and Tube Wiring

Introduction

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:

• Fire hazard - The old, brittle insulation can crack and expose bare wires, allowing arcs, sparks, and overheating. This significantly increases fire risk.

• Shocks and electrocution - Damaged insulation exposes live wires, which can lead to shocks and electrocution if touched. Loose connections can also spark and arc.

• Lack of grounding - Knob and tube wiring typically lacks a ground wire, which protects against shocks and allows faults to safely trip breakers. Ungrounded wiring can energize metal surfaces, shocking anyone who touches them.

• Overloading - Knob and tube wiring wasn't designed to handle the power demands of modern appliances and electronics. Overloaded circuits can overheat, arc, and cause fires.

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

• Wear safety goggles, gloves, and a mask to protect yourself from dust and debris during the removal process.

• Have a fire extinguisher readily available in case any old wiring starts to spark or smoke during handling.

Tools Needed

• Wire cutters and wire strippers to remove old wiring from connections.

• A voltage tester to confirm wires are actually dead before touching them.

• A headlamp or work light to illuminate dark areas like attics and crawlspaces.

• Basic hand tools like screwdrivers, wrenches, pliers, and hammers to take apart framing and access junction boxes.

Electrical Permits

• Obtain any necessary permits from your municipality to replace old wiring and ensure the new wiring meets local code requirements.

Hire an Electrician

• Consider hiring a licensed electrician, especially if you lack experience with electrical projects. They can ensure the wiring is correctly handled and safely removed.

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:

• Have a licensed electrician install new grounded Romex wiring throughout your home to replace the old knob and tube wiring.

• The electrician should also install any additional circuits, outlets, lighting, etc. that are needed to meet current electrical code and usage needs.

• Obtain an electrical inspection once the new wiring installation is complete. Doing a full rewiring allows your home's electrical system to meet the most up-to-date safety codes.

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.