Upgrading Knob-and-Tube Wiring in Older Homes

What is Knob-and-Tube Wiring?

Knob-and-tube wiring was commonly installed in homes built before the 1940s. It features insulated wires running through open air, Supported by ceramic knobs and tubes.

This old form of electrical wiring has some notable drawbacks:

Why Upgrade from Knob-and-Tube Wiring?

There are several compelling reasons to upgrade old knob-and-tube wiring:

Options for Replacing Knob-and-Tube Wiring

You have two main options when upgrading old wiring:

Complete Rewiring

This involves removing all the old knob-and-tube wiring and installing entirely new wiring throughout the home.




With this approach, the existing wiring is left in place. New wiring is run alongside it, connecting to the old wiring via junction boxes.



I recommend getting quotes from licensed electricians for both options. While pigtailing is cheaper upfront, a full rewire may pay off long-term in safety, efficiency, and resale value.

Cost to Upgrade Knob-and-Tube Wiring

The cost to replace knob-and-tube wiring ranges from $3,000 to $15,000 depending on:

Many homeowners spread out the wiring upgrade over time to save on costs. Prioritize high-load circuits like kitchens first.

Electrical Code for Knob-and-Tube Wiring

The National Electrical Code (NEC) contains regulations related to knob-and-tube wiring:

Work with certified electricians to ensure any knob-and-tube upgrades meet all applicable codes. Permitted work can add value by making the home safer and more sellable.

Is DIY Wiring Replacement Possible?

I do not recommend DIY electrical work when upgrading knob-and-tube wiring. The risks of improper installation are too great, including:

Electrical work also requires permits and inspections. Licensed electricians have the experience, tools, and know-how to safely replace old wiring. The peace of mind is well worth the investment. Attempting DIY wiring upgrades can endanger your most valuable asset - your home.

Finding Professional Help

Start by getting quotes from multiple licensed electricians when replacing knob-and-tube wiring. Look for these key qualifications:

Check reviews and ask for referrals from past customers. A little research helps find the best electrician for your wiring replacement needs.

Upgrading outdated knob-and-tube wiring improves safety, reliability, and efficiency. By following the guidance in this article, you can successfully modernize the wiring in your older home.