Why You Should Reconsider Upgrading from Knob and Tube Wiring

What is Knob and Tube Wiring?

Knob and tube wiring was an early standardized method of electrical wiring used in North America from about 1880 to the 1940s. It consisted of single insulated copper conductors run within wall or ceiling cavities, passing through joists and studs.

The wiring was supported by knobs attached to the structural framing, and connections were made via tubes rather than junction boxes. This old type of wiring has largely been phased out and replaced with modern sheathed cable or conduit wiring methods.

Safety Concerns with Knob and Tube Wiring

While knob and tube wiring was considered safe when it was first introduced, it does not meet today's electrical safety standards in several ways:

• No grounding - There is no equipment grounding conductor, increasing the risk of shock. Grounded circuits are now required in new wiring systems.

• Insulation degradation - The insulation on old wires often deteriorates over time, increasing the chance of short circuits and fire.

• Overloading circuits - The wiring is not designed to handle the higher wattage of today's modern appliances and devices.

• Exposed wires - Knob and tube wires are separate and often run through open spaces, so they are more prone to physical damage.

• Difficult maintenance - It can be challenging to maintain and repair knob and tube wiring due to access issues.

Limitations of Knob and Tube Wiring

Beyond safety issues, knob and tube wiring also presents other drawbacks:

• Low capacity - The wiring is insufficient for today's electricity demands. Lighting and appliance circuits are usually only 15 or 20 amps.

• No ground wires - Ungrounded receptacles can damage electronics and computers without surge protectors.

• Insurance issues - Many insurance companies will not insure a home with knob and tube wiring due to fire risk.

• Resale value - Homes with knob and tube sell for 10-25% less than similar homes with modern wiring.

• Difficulty with upgrades - It can be challenging to add new circuits without extensive rewiring.

Benefits of Upgrading from Knob and Tube Wiring

Replacing the old knob and tube wiring in your home offers a number of advantages:

• Improved safety - Modern wiring is well-grounded and eliminates the risks of exposed, degraded insulation.

• Increased property value - Upgraded electrical can increase your home's value significantly.

• Higher capacity - You can easily support additional lighting, appliances, electronics and devices.

• Added convenience - It's easier to add new circuits and outlets.

• Peace of mind - Reduce the risk of electrical fire. Many insurance companies prefer modern wiring.

Steps for Upgrading Knob and Tube Wiring

Upgrading wiring in a home is a major project that requires planning and licensed electricians. Key steps typically include:

• Hiring a licensed, insured electrician to design a new wiring plan.

• Getting all required permits from the local building department.

• Removing old knob and tube wiring, including all conductors.

• Installing new wires, junction boxes, receptacles and switches.

• Ensuring proper grounding and bonding.

• Adding new circuits for kitchen, laundry, bathrooms, home office, etc.

• Passing final inspections by the building department.

Cost to Upgrade Knob and Tube Wiring

The cost to replace knob and tube wiring varies greatly by factors like:

• House size and number of circuits

• Accessibility to wiring runs

• Geographic location and labor rates

• Scope of additional upgrades

Typical range:

• Small house with minor upgrades: $8,000 - $12,000

• Medium house with moderate upgrades: $15,000 - $25,000

• Large house with significant upgrades: $30,000+

Get estimates from multiple electricians before proceeding. The upgrade cost can pay for itself over time in improved home value, safety and convenience.

Conclusion

While rewiring a home is a major investment, upgrading from old knob and tube wiring provides significant safety and performance benefits. I would strongly recommend having it professionally replaced by a licensed electrician to modern electrical standards. The upgrade cost can pay off in the long run.