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Fire Insurance

Knob & Tube Wring: A Possible Home Insurance Deal Breaker

By March 3, 2011 February 26th, 2019 No Comments

Many of the homes in Lancaster County are older with great architectural detail and character. However, one of the less attractive historical features, from an insurance perspective, can be the “knob and tube” wiring that is commonly found in homes built prior to the 1930’s. As a result, homebuyers may have trouble finding a Homeowners Insurance company that will insure a home with knob and tube wiring.

What is “knob and tube” wiring?

Knob and tube wiring is an electrical wiring method that was commonly installed in buildings between the 1880’s to the 1930’s. The system uses porcelain “knobs” to support the wiring and to keep it away from the potentially combustible framework. Ceramic “tubes” are used to run wires through beams, rafters and walls and to prevent the wires from being compressed by wood when the house settles.

Why are insurance companies so cautious about knob and tube wiring?

• General deterioration, since the wiring is 60+ years old

• Knob and tube has no ground wire like modern electrical systems which can be an increased fire hazard

• The original electrical wiring may have had additional branches and outlets improperly installed over the years, that may overheat the wiring and disintegrate the insulation protection

• Power demand from modern technology can exceed the original supply design and lead to blown fuses

• Animals love to chew off the insulation protection which can exposure “live” wires to flammable materials

• Homeowners install additional thermal insulation in the attic that covers the wiring and suffocates the wiring from the open air needed for cooling

What should a homebuyer do if they are purchasing a home with knob and tube wiring?

• Get your insurance agent involved as soon as possible. Every carrier has different underwriting guidelines and different requirements on how to handle homes with knob and tube wiring. Some insurance carriers may not even insure a home if it has any knob and tube wiring and those carriers that accept the knob and tube “as-is” could be very expensive.

• Have a licensed electrician certify the entire electrical system. Not only will this ensure that the electrical system meets current code, some insurance carriers may accept certified knob and tube wiring at their standard home insurance rates.

• Replace the knob and tube wiring. Of course this is the most expensive solution but the expense and hassle may be worth the peace of mind for you and your family.

Overall, insurance for a knob and tube home is handled on a case by case and carrier by carrier basis. Find out early what an insurance carrier requires so that you don’t have any surprises prior to closing.