What is Knob and Tube Wiring?

Knob and tube wiring was an early standardized method of electrical wiring used in buildings from about 1880 to the 1940s. It consists of insulated copper conductors run through protective tubes or knobs, which act as spacers to prevent contact between wires.

Some key characteristics of knob and tube wiring:

While knob and tube wiring was safe when installed correctly, it can become hazardous as it ages. Fraying insulation, improper splices, overloaded circuits, and lack of grounding are concerns.

Dangers of Old Knob and Tube Wiring

There are several potential dangers associated with old or damaged knob and tube wiring:

The risks of knob and tube wiring grow as systems age. Periodic inspection and limited use of high-power devices can help mitigate hazards in the short term. Ultimately though, replacement provides the only reliable solution.

How to Troubleshoot Problems

Troubleshooting knob and tube wiring yourself involves several steps:

Visual Inspection

Check Connections

Assess Circuits and Fuses

Check Insulation

Test Hazards

Document and Label System

When to Call an Electrician

While many knob and tube issues can be troubleshooted yourself, it is safest to have a professional handle any repairs or replacements. Seek electrician help if you discover:

Replacing knob and tube wiring completely is the ideal long term solution. An electrician can assess your system's condition and outline replacement options given your home's layout and budget.

Many electricians offer special expertise working on older homes. When selecting a pro, look for:

Avoid attempts to simply pigtail or cap off old wiring. This leaves hazards in place rather than eliminating risks. Insist on full removal for safety.

Safety Tips for the Homeowner

When contending with older knob and tube wiring, keep these safety tips in mind:

Periodic troubleshooting and strictly limiting use of high power devices can temporarily mitigate risks until wiring can be fully updated. But reaching out to an electrician should be your first call when dealing with any knob and tube concerns.