How to Rewire Your Home Using Obsolete Knob and Tube Wiring

Introduction

Rewiring a home with obsolete knob and tube wiring can be a daunting task, but with proper planning and precautions it can be done safely. Knob and tube wiring was commonly installed in homes built before 1950. It features insulated wires that are separated by ceramic knobs and run through hollow tubes, unlike modern wiring that runs through protective conduits. While knob and tube can still function safely if undisturbed, it becomes hazardous when homeowners add new wiring, outlets and appliances that overload the system. A full rewire is the only way to bring the home up to modern electrical standards. This guide will walk through the key steps I took to successfully rewire my home using knob and tube.

Dangers of Knob and Tube Wiring

Before deciding on a rewire, it's important to understand the risks of keeping obsolete knob and tube wiring:

• Fire hazard: The insulation on knob and tube wiring becomes brittle over time, leading to cracks and exposed wires. This can spark fires inside walls. Knob and tube also lacks safety devices like circuit breakers.

• Insufficient for modern loads: Heavy use of electricity can overload the limited capacity of knob and tube. This leads to dimming lights, blown fuses andTripped circuit breakers.

• Difficult to modify: It's extremely dangerous for amateurs to tap into knob and tube or add new wiring. This often leads to fire risks.

• Lower property value: Most buyers are wary of homes containing knob and tube, making it harder to sell. Some mortgage lenders even refuse financing.

For these reasons, I decided a complete rewire was necessary to protect my home and family.

Preparing for a Rewire Project

Careful planning and preparation is crucial when taking on a rewire project. Here are some key steps I took before getting started:

• Consult an electrician - Have a licensed electrician inspect your knob and tube wiring and provide a cost estimate for rewiring. Their expertise is invaluable.

• Research permits - Check with your local building department about required permits and inspections for rewiring a home.

• Have an evacuation plan - Select a relative or friend's home where your family can stay during the rewiring process.

• Take photos - Document the existing wiring setup for reference.

• Clear access paths - Remove insulation and debris blocking access to wiring paths like the attic and basement.

• Turn off power and reroute - The electrician will need to power down circuits and temporarily reroute power sources.

• Budget appropriately - Rewiring a whole home can cost $8,000 to $15,000. Be sure to get multiple estimates.

Rewiring Process Step-by-Step

With proper prep work done, I was ready to have the electrician rewire my home. Here is an overview of the process:

1. Running New Wiring

• Electrician accessed wiring paths like the attic, basement and walls.

• They drilled small holes to thread new wires between access points.

• Modern NM cables were run from the electrical panel to each outlet and switch.

• Exposed knob and tube wires were left in place for now.

2. Installing the New Electrical Panel

• The old 60 amp fuses were insufficient, so the electrician installed a 200 amp circuit breaker panel.

• It was connected to the utility feed and grounding rod. This would distribute electricity throughout the new wiring system.

3. Connecting the Wires

• The electrician carefully labeled each wire running to outlets, switches and appliances.

• They then connected the NM cables to the appropriate circuit breakers.

• Old knob and tube wires were fully disconnected from the panel.

4. Removing Old Wiring

• Once energized through the new wiring, the electrician went back and fully extracted all accessible knob and tube wires.

• They checked that no live current remained in the old wires for safety.

• Any remaining inaccessible knob and tube was capped off and marked.

5. Finishing Touches

• With the new wiring live, the electrician tested each outlet and switch for proper function.

• They installed GFCI outlets in bathrooms, kitchen, laundry and other wet areas.

• Any holes or damaged surfaces were patched up and restored to their original state.

Performing Safety Checks

Before moving my family back into the home, I wanted to personally double check for safety:

• Verify the new panel and all circuits function properly. Flip breakers on and off.

• There should be no exposed wires anywhere now that knob and tube is contained.

• All outlets and switches should have proper cover plates.

• Use a non-contact voltage tester to confirm there's no current in any remaining old wiring.

With the rewire complete, I now have reliable and safe electrical service that makes my old house feel new again! While rewiring a home is costly, it is a worthwhile investment that also increases the property value significantly. By following safety precautions and hiring a skilled electrician, your obsolete knob and tube wiring can be successfully replaced.