What is Knob and Tube Wiring in Older Homes?


If you have just bought an older home or acquired your old family home, it might seem quaint. But there is a good chance it is in dire need of an upgrade. This could be plumbing, the electrical system, as well as some structural damage.

One of the problems with older homes is the electrical system. It is not capable of handling everything it will be required to do. Now, we have so many more electrical appliances that simply were not used 100 years ago.

What is Knob and Tube Wiring?

This type of wiring was used around 1900 but continued to be popular up until the 1950s, perhaps beyond that. These are easily recognizable from their white, ceramic, spool-like knobs and connecting tubes.

The electric wires go through the knobs, and these support each individual wiring strand. Heavy ceramic tubes protect wires where they run through joists.

Many older homes will still have this type of electrical system, even if you can’t see it. These can be hidden behind the walls or in the ceiling, and the only way to know for sure is to make a hole in the wall to check.

Buying or Inheriting a House With Knob and Tube Wiring

If you have just found your dream home, or have recently taken ownership of an older home, you will have to have it inspected. Your insurance company will ask about the type of electricity your home uses.

Keeping the older system may make it awkward for getting financing or insurance for the home. You have to have it all inspected and an electrician must submit a contract stating that the knob and tube wiring will be replaced within 60 days to your insurance agent.  Once the job is complete, a receipt indicating completion must be submitted.

Why Should I Replace It?

Knob and tube wiring is a safety concern, for sure. They used rubber or cloth insulation which can wear out or disintegrate. Once this happens, it is a real fire hazard.

There is a good chance these wires and the tubes are brittle and falling apart. Once that happens, the wires are exposed and can start a fire.

You may not be aware of all the alterations that this electrical system has undergone. The previous owners may have spliced wires, added wires, or makeshift repairs. It is difficult to find replacements so adjustments will have been made.

These systems are not meant to handle the types of appliances we have now. Larger and more powerful appliances like TVs, washers and dryers, air conditioners, computers, it’s just not prepared to cope with that much stress.

If you have knob and tube wiring, have it replaced and upgraded. It will be better for safety reasons, it will have an effect on your insurance, and your home will function much better.

Safety First

We ask a lot of our electrical systems. Clearly, the knob and tube system will have to go. Before you make an offer on an older house with knob and tube wiring, ask your electrician how much it will be to replace it. You may get a better deal on the house, or ask the seller to have it removed, first.

Fusion Electric can help you through every step. They will inspect the home, to see if the wiring is old and knob and tube, see what condition it is in, and help you make decisions about replacing it.

Call today with any questions you may have about older wiring or any electrical issues you may have.



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