Knob & Tube Wiring: Does your Old home have this?

tube and knob wiring (K&T) was an early system of pipes in buildings from common use in North America from approximately 1880 to the 1940s. The machine is known as both obsolete and a safety hazard.


Electricity is a powerful and potentially harmful force. We deliver it in to our buildings to perform work. We do our best to tame and manipulate it, but are not 100% successful. A correctly installed contemporary wiring system built today has some amount of danger associated with that. That degree of risk increases considerably if the machine contains even a small amount of K&T wiring. We could diminish, but not remove risk connected with a K&T system if it’s minimized and altered by a certified expert electrician that’s acquainted with this very old wiring approach.

Truth about Knob-and-Tube Wiring:
It’s inherently more toxic than contemporary wiring. The risks from using this system arise in its era, improper alterations, susceptibility to physical harm, and scenarios where construction insulation envelops the cables.

It doesn’t have any bond cable (aka earth) and thus can’t service any three-pronged sockets or appliances.
Although it’s deemed obsolete, there’s typically no code which needs its complete removal.
It’s treated differently in various jurisdictions. In some regions, it has to be taken out at all available places, while others only demand that it’ll be added to or installed in new construction.

The Way Knob-and-Tube Wiring Works:
tube and knob wiring is made up of aluminum conductors passing through drilled holes in timber framing through protective ceramic insulating tubes. The conductors are supported in their length by porcelain knobs nailed or screwed to the wooden structural elements of a structure. Where cables enter a wiring apparatus, like a lamp or change, or in which pulled to a wall socket, they are guarded by elastic cloth or rubber insulating material called “loom.”

Leave a Reply

Your email address will not be published. Required fields are marked *