Knob & Tube Wiring

Knob-and-tube (K&T) wiring was an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the 1940s. The system is considered obsolete and can be a safety hazard, although some of the fear associated with it is undeserved.

K&T wiring is designed to dissipate heat into free air, and insulation will disturb this process. Insulation around K&T wires will cause heat to build up, and this creates a fire hazard. The 2008 National Electrical Code (NEC) requires that this wiring system can not be covered by insulation. Specifically, it states that this wiring system should not be in hollow spaces of walls, ceilings and attics where such spaces are insulated by loose, rolled or foamed-in-place insulating material that envelops the conductors.

Many insurance companies refuse to insure houses that have knob-and-tube wiring due to the risk of fire. Exceptions are sometimes made for houses where an electrical contractor has deemed the system to be safe.

• Here are some tips for those of you with K&T wiring:
• The homeowner or an electrician should carefully remove any insulation that is found surrounding K&T wires.
• Prospective home buyers should get an estimate of the cost of replacing K&T wiring. They can use this amount to negotiate a cheaper price for the house.
• Have the system evaluated by a qualified electrician. Only an expert can confirm that the system was installed and modified correctly.
• Do not run an excessive amount of appliances in the home, as this can cause a fire.
• Where the wiring is brittle or cracked, it should be replaced.
• Proper maintenance is crucial.

If you live in a home with K&T wiring then call the licensed electrical experts at Leinster Electric today and we will do a complete evaluation of your electrical system and tell you whether or not it is safe. We will also supply you with other available options for upgrading your current electrical system.

Please contact Leinster Electric at 973-349-4184 or use our online form to a request an appointment to see how our expert residential electricians can help you with knob and tube wiring!