Knob and Tube Wiring

Most homes built before the 1950's have knob and tube wiring. You can determine if you have this type of wiring in your home, by closely inspecting basement joists or attic rafters.

To determine if your house is wired with knob and tube, look for ceramic knobs or tubes in which the wire gets secured to, or passes through, joists, studs, etc. If knob and tube wiring is not easily seen or accesible, you can check your electrical outlets. You may only have two prong outlets to plug into. Basically, no ground at each outlet or fixture outlet means knob and tube wiring is present.

Homeowners with knob and tube wiring may find it difficult to obtain insurance on their home because some insurance companies are reluctant to insure a house they perceive as risky. Insurance companies may require a certificate of inspection from a qualified electrician, before it will insure a home with knob and tube wiring. If the electrician gives a satisfactory assessment of your home, the company may consider giving an insurance policy for your house.