How to Safely Upgrade Your Home's Knob and Tube Wiring

Introduction to Knob and Tube Wiring

Knob and tube wiring was commonly installed in homes built before 1950. This old wiring system consists of individual wires that are run through the walls, attic, and crawl spaces. The wires are supported by ceramic knobs and tubes, which is how the system got its name.

While knob and tube wiring was suitable for the electrical needs of older homes, it can be dangerous by today's standards. The insulation around the wires becomes brittle over time, leading to exposed conductors. In addition, knob and tube lacks a ground wire, which is essential for preventing shocks and damage to modern electronics.

Upgrading from knob and tube wiring is highly recommended for safety, but it can be a complicated process. This article provides a step-by-step guide on how to safely upgrade your home's old wiring.

Dangers of Knob and Tube Wiring

Knob and tube wiring poses several serious risks, including:

• Fire hazard - The insulation breaks down over time, allowing wires to overheat. This can ignite surrounding combustible materials.

• Shock hazard - Exposed conductors increase the risk of electrical shock. The lack of grounding also removes an important safety mechanism.

• Insufficient capacity - Knob and tube wiring lacks the capacity to handle the increased electrical loads in modern homes. Overloaded circuits can overheat and fail.

• Difficulty finding insurance - Many insurance companies won't insure homes with knob and tube wiring due to the risks.

• Lower property value - Outdated wiring scares away potential buyers and lowers your home's value.

These dangers demonstrate why upgrading old wiring is so important for safety.

Evaluating Your Current Wiring

Before planning an upgrade, you'll need to thoroughly evaluate your existing knob and tube wiring:

• Inspect the attic and crawl spaces - Look for knob and tube wiring and check its condition. Look for cracked or damaged insulation.

• Check outlets and switches - Symptoms like flickering lights, discolored outlets, and warm switches indicate wiring issues.

• Consider an electrician's assessment - An expert can identify all the existing wiring and detect any hidden dangers.

• Review your electrical capacity - Determine if the wiring meets the needs of your family and modern appliances.

Document any wiring hazards you discover. This will help in planning the scope of the rewiring project.

Creating a Rewiring Plan

Upgrading your wiring system requires careful planning:

• Decide which sections to rewire - Focus first on areas with known hazards or insufficient capacity.

• Choose a new wiring method - Romex wiring is the common standard for modern homes.

• Consider layout changes - This is a good opportunity to add new circuits or move outlets.

• Include other upgrades - Many pros recommend upgrading your electrical panel at the same time.

• Hire an electrician - Unless you're very experienced, electrical work should be handled by a licensed pro.

• Get all necessary permits - Most areas require permits for rewiring projects.

• Determine timeframe and budget - Rewiring a whole home can take days or weeks. Create a detailed budget.

Thorough planning makes the rewiring process smoother and helps avoid unexpected costs.

Safely Installing New Wiring

When it's time to install new wiring, focus on doing it safely:

• Turn off power at the main panel - Lock out the main breaker switch and tag it "OFF."

• Test wires before handling - Verify power is off using a non-contact voltage tester.

• Work carefully in the attic - Attics have limited visibility and can be uncomfortably hot.

• Inspect all existing wiring - Look for damage and only interact with knob and tube wiring as necessary.

• Keep plumbing and electrical separate - Don't run wires directly over or next to pipes.

• Use appropriate materials - Follow code requirements for things like conductor gauge and box fill.

• Connect new ground wires - Grounding provides crucial shock protection.

Follow all electrical codes and safety practices throughout the installation process.

Removing Old Wiring

Ideally, you should fully remove the old knob and tube wiring once new wiring is installed. This eliminates any remaining safety hazards.

When removing old wiring:

• Seal up openings - Fill any holes made to feed the wiring into walls to maintain fire blocking.

• Pull wires carefully from attic - Don't tug wires aggressively to avoid damage.

• Cap all unused wires - Install wire nuts on the ends of any wires that will remain dormant in the walls.

• Dispose of properly - Knob and tube wires are typically coated in lead-based insulation. Follow hazardous waste guidelines.

• Consult experts if needed - Licensed electricians have the training to remove old wiring safely.

Taking the time to fully remove knob and tube wiring gets your home wiring back to a like-new condition.

Final Inspections and Completing the Project

The final steps in finishing your wiring upgrade project include:

• Schedule rough and final inspections - Inspections ensure work was completed to code.

• Install cover plates - Securely attach cover plates to all boxes and outlets.

• Label new circuits - Update your electrical panel with labels for all new circuits.

• Check all devices - Test lamps, appliances, and other electrical devices to ensure proper function.

• Consider smoke and CO detectors - Now is an ideal time to install or replace detectors.

• Update home insurance - Inform your insurance company of the completed wiring upgrades.

Following proper final checks and inspections gives you peace of mind that your home's electrical system is now safe and code-compliant.

Upgrading old and dangerous knob and tube wiring requires careful planning and installation. But it's a very worthwhile project that greatly improves electrical safety and adds value to your home. Just be sure to involve a licensed electrician unless you have extensive electrical experience yourself.