Knob-and-Tube Wiring

Knob-and-tube wiring is an early electrical system used in homes built roughly from the 1900s through the 1940s. It runs individual wires through ceramic knobs and tubes rather than the grounded cable used today. Because so much of the Rhode Island and Massachusetts housing stock dates to that era, a home inspection on an older home may find some still in place. The wiring is not automatically unsafe, but it lacks a ground, can become brittle with age, and is easy to overload with modern appliances. Many insurers and lenders will ask that active knob-and-tube be updated before they will write a policy or fund a loan. If an inspection finds it, the usual path is an electrician's evaluation and a plan to replace it, which becomes a negotiation point between buyer and seller.