Bellingham Real Estate Inspection (King of the House) Live Knob and Tube Wiring

In an older home, the home inspector should attempt to determine if energized knob and tube wiring is present. It is not always possible to definitively make that determination, but often it is possible to do so. In fact, frequently it is fairly easy to state, no doubt about it, that there IS energized knob and tube wiring. It is more risky, and often harder to determine, that there is NO LIVE knob and tube wiring at an old home that was built in the era when knob and tube was the system of choice -- the era of Edison up into the 1950's.

Here I will take my readers behind the scenes at a recent inspection in Bellingham. The house is pre-1900's, so there was no question about it that knob and tube wiring had been present at some point. One of the likely locations to find the remnants of the old wiring, and to access it to check if it is hot or not, is up in the attic. The first scene was taken right after I popped the hatch cover. I am looking for signs of the wiring, figuring it would be there somewhere -- live or disconnected.

This second video was taken while I was traversing the attic and testing the circuits that I saw. This was an easy one because I knew right away that the wiring was live. For the record, the neutral side of the circuits will not test as live, but the other (hot) side will activate the voltage alert tester. When an inspector checks knob and tube circuits, it is important to make sure that both sides of the wiring are tested. Checking only the neutral, and stating the wiring was disconnected, can lead to big problems and misinformation.

There you go! Live knob and tube wiring. If you are interested in the history of, and the potential complications of knob and tube circuits in today's houses, please click on the video below.