What Is Knob and Tube Wiring, and Is It Hiding in Your Home?

What is knob and tube wiring? While it might sound like a bad 1990s indie band, it’s actually an outdated electrical system that’s still found in many old homes in the United States.

Often abbreviated as K&T, this early standard—widespread in residences built from the 1880s to the 1930s—is often considered a hazard today, depending on how it was installed.

So if a home you’re hoping to buy has it, you’ll want to have it examined closely and possibly replaced. Why?

Here’s everything you never knew you needed to know about ye olde knob and tube.