How to Safely Replace Old Knob and Tube Wiring

Knob and tube wiring was commonly installed in homes built before 1950. While it was suitable for the electrical needs at the time, this old wiring can be dangerous by today's standards. Replacing knob and tube wiring involves understanding the risks, planning the project, hiring an electrician, and following important safety steps.

Dangers of Knob and Tube Wiring

Knob and tube wiring has significant risks that make replacement vital for safety:

• Fire hazard - The old, brittle insulation can crack and expose bare wires that can arc, spark, and ignite fires. Knob and tube wires run through open spaces and can contact flammable materials.

• Shocks and electrocution - Damaged areas in the insulation can energize metal components like ducts and pipes. This can lead to dangerous electrical shocks.

• Insufficient for modern loads - Lighting and appliances today require much more power than old wiring was designed for. Overloaded circuits can overheat and fail.

• Difficult to repair - The wiring is difficult to access and replace. Attempting DIY repairs risks making dangerous errors.

Considering these severe risks, having knob and tube wiring in a home is very unsafe. Replacement should be a top priority.

Planning Your Knob and Tube Replacement Project

Replacing knob and tube wiring is a major electrical project that requires careful planning:

• Have an electrician inspect - A licensed electrician should assess the full scope of knob and tube wiring and provide a detailed replacement plan.

• Evaluate time/costs - Projects can take weeks to months and cost thousands of dollars depending on the home's size and complexity. Evaluate your budget and schedule.

• Determine scope - Consider if you'll replace all wiring or just some sections. Full rewiring is ideal but may not be feasible cost-wise.

• Decide on electrical panel upgrade - A new panel may be recommended to handle added circuits. This will increase costs but improves safety.

• Plan for repairs - Some walls/ceilings may need repairs after removing old wiring. Factor this into the project timeline and budget.

• Schedule electrician and permits - Book a licensed electrician far in advance and apply for the required permits from your municipality.

• Identify power plan - Determine how you'll provide temporary power during the rewiring if needed. Options include generators or extending a neighbor's power line.

Thorough planning and preparation will help the project go smoothly and safely.

Hiring an Electrician

A licensed electrician should always be hired to replace knob and tube wiring. Some key tips when hiring an electrician:

• Verify they have an active local license.

• Ask for proof of liability insurance and bonding.

• Ask for references from past wiring replacement jobs.

• Get multiple upfront estimates. Be wary of extremely low bids.

• Choose an electrician you trust. They should demonstrate knowledge about safely replacing old wiring.

• Agree on a detailed written contract covering all project specifics like timeline and payment schedule.

• Make sure they will get the proper permits before starting work.

Taking the time to hire the right electrician helps protect your family's safety during such a major electrical project.

Safety Precautions During the Rewiring Process

Critical safety precautions must be followed during the knob and tube replacement process:

• Turn off power - The main breaker should be shut off before starting. Use a contact voltage tester to be sure power is off.

• Disconnect wires carefully - When removing old wiring, be very careful not to contact live wires. Wear insulated gloves and eye protection.

• Keep others out of work areas - No one should be present in rooms where the electrician is actively replacing wiring.

• Ventilate when sealing openings - Use a fan or ventilator when sealing old wiring openings to avoid smoke buildup.

• Mount electrical boxes securely - New boxes must be mounted securely and with correct distances to avoid vibration and heat hazards.

• Use GFCI outlets near water sources - Update outlets near kitchen/bathroom plumbing fixtures to GFCI outlets to prevent shocks.

• Label new circuits clearly - Each new circuit should be labeled correctly in the panel to prevent overloads.

• Perform inspections - Thoroughly inspect all new wiring before re-energizing the system. Check for loose connections, bare wires etc.

Following safety protocols is crucial when undertaking major electrical work to avoid fires, shocks, electrocution, or other hazards.

Final Testing and Inspection

As a final step, the new wiring system should be thoroughly tested and inspected before completing the project:

• The electrician should test all outlets and light fixtures to verify proper operation.

• Thermal imaging can check for hot spots that indicate loose connections.

• A megger test can check for adequate insulation resistance.

• The local building inspector will assess if all code requirements are met and issue final approval.

• Operate all electrical devices simultaneously to confirm no circuit overloads.

• Check that all junction box covers and faceplates are properly secured.

• Verify no wires are pinched by insulation or building materials.

Only once all tests and inspections pass should drywall patching begin and power be fully restored to the home.

Replacing hazardous old knob and tube wiring requires careful planning, hiring an experienced electrician, and rigorous safety steps during the process. But once completed, you gain tremendous peace of mind knowing your home's electrical system is completely safe and up-to-code. The investment is well worth it for your family's safety.