Getting To Understand Knob And Tube Wiring

If your home was built before 1950, and hasn’t been fully rewired, it might have knob and tube wiring. If that is true, it is very likely you had a problem once you attempted to get home insurance. But when the knob and tube wireing was well preserved, and has not been utilized as a clothing line in the basement, it might be just nice.

What’s knob and tube wiring?

You won’t find any knob and tube wiring in newer homes, however when your home was constructed in 1950 or earlier, have a look at the basement. If you discover wires running via ceramic cylinders or “tubes” inserted into the holes in the wooden floor joists, you’ve knob and tube wiring. You will also find ceramic “knobs”, which retain the wires from touching the timber along which the cables operate. The wires are often insulated with a rubberized fabric.

One of the main differences between modern wiring and also the old knob and tube, is that with knob and tube there’s absolutely no ground wire. Additionally, the black and the white wires operate individually, not together in a single enclosed sheath much like modern wiring.

You might have found it hard to receive home insurance in case your home has knob and tube wiring. In reality, this kind of wiring isn’t inherently harmful. Problems arise if the insulation around the wires starts to deteriorate with age, or even if home handymen have made adjustments to the wiring. As mentioned, there’s absolutely no ground wire, therefore this kind of wiring can’t adapt any electrical objects with 3 pronged plugs.

There’s not anything in the construction code in Canada which says knob and tube wiring has to be eliminated from existing homes, however it’s deemed obsolete, and cannot be utilized in any new structure.