How to Replace Outdated Knob and Tube Wiring

How to Replace Outdated Knob and Tube Wiring


Replacing knob and tube wiring can seem like a daunting task, but with the right preparation and safety precautions, it is quite doable as a DIY project. Knob and tube wiring was an early standardized method of electrical wiring used in North America from about 1880 to the 1930s. While it was safe when initially installed, this outdated wiring can be a fire hazard today due to deterioration over time. Replacing it completely with modern wiring enhances safety and allows your home's electrical system to be upgraded.

Reasons to Replace Knob and Tube Wiring

There are several important reasons to replace knob and tube wiring:


Insufficient Capacity

Inability to Support Modern Appliances

Energy Efficiency

Develop a Wiring Replacement Plan

Careful planning makes a wiring replacement project go smoothly:

Safety Precautions

Always make safety the #1 priority when replacing old wiring yourself:

Removing Knob and Tube Wiring

The first step is removing the old outdated wiring:

Gather Necessary Materials

Access the Wiring

Detach Wiring

Remove Fixtures

Clean Up

Installing New Wiring

Follow these best practices when installing replacement wiring:

Run All New Wire

It's usually not up to code to just remove the unsafe knob and tube runs and splice to newer wiring. Fully new runs are safer.

Use Proper Materials

Follow codes for approved insulation type, gauge wire size, junction boxes, and other materials. Using quality materials prevents dangerous shorts and fires.

One Circuit at a Time

Focus on removing the old wiring and installing new wire for one complete circuit before moving to the next. This organized approach prevents confusion.

Label Thoroughly

Use colored tape and numbered tags to label each wire run and junction. This makes it far easier to match up when connecting fixtures and devices later.

Use Safe Installation Methods

Follow best practices like:

Get Inspected

Have an electrician or city inspector verify safety at key checkpoints like inspecting junction boxes before close-up.

Connecting Fixtures and Devices

Finish off by connecting all fixtures like lights, outlets, switches and appliances:

Following safe practices and taking it step-by-step allows a homeowner to successfully replace old knob and tube wiring. The result is a safer, more robust electrical system ready to meet all your home's wiring needs.