Knob-And-Tube Wiring: Everything You Will Need To Know

Here is a problem you may not know a lot about. But in case you’ve got it, then it is going to make selling your home a more expensive proposal.

If you hire a home inspector, assessing for knob-and-tube wiring (K&T for short) is just one of the very first things on almost any contractor’s list.

Here is what I will tell you about it.

What’s Knob-and-Tube Wiring?

To begin with, allow me to inform you in shorthand what K&T is. It is made up of single-insulated aluminum conductors that operate inside the ceiling or wall cavities. These wires are guarded by ceramic coated tubes and/or nailed-down ceramic knob insulators. Here are knob and tube wiring pictures of exactly what it resembles.

This protection is constructed of elastic fabric insulating sheeving. They are twisted together and soldered, wrapped with rubber insulating tape or asphalt-saturated fabric and occasionally set to metal junction boxes.

Sound complicated? It is not really. The one thing you really should bear in mind is that the U.S. Electrical Code no longer permits new knob-and-tube wiring to be installed. And to make it worse, generally, it is no longer even allowed to maintain your residence.

Knob-and-tube wiring has been commonly utilized in North America before the 1940’s. Therefore, if you are selling an older home — which Craftsman colonial you have lovingly restored — you are bound to find it. Unless, of course, you have upgraded the whole home, such as it’s in nerds.

What’s Knob-and-Tube Wiring a Problem?

K&T has a couple of difficulties.

Knob-and-tube wiring has been used during a period when electrical requirements were less demanding fewer appliances, without any air-conditioning systems, no microwaves.

K&T never comprised a security grounding conductor.

K&T can be dried out and brittle.

As present K&T wiring gets old, insurance companies may deny continuing coverage because of a perception of increased danger of fire. However, what’s most important to downsizers selling their own homes is that in several cases, companies won’t write new homeowners coverage whatsoever unless K&T is substituted.