Electricity leaking out of Knob and Tube

Your home’s electrical system comprises two types of materials: conductors and insulators. We use copper for the wires because it conducts electricity well. These wires have a wrapping of an insulating material that does not conduct electricity. We call this material an insulator. The first wiring system, known as knob and tube, used two methods for insulation. A cloth soaked in tar wrapped around the copper wire, and gaps were created with the use of knobs and tubes to separate the wire from other flammable materials. When first installed, the original cloth insulation was insufficient. As the material ages, its insulating ability decreases.

Open Junction box showing typical cloth wire

Old wiring becomes unsafe over time.

Knob and tube wiring was a fancy way to do electricity a long time ago. Now it’s not safe. There are a few reasons. First, the rubber insulation gets old and falls apart, which leaves the metal wires all exposed. Next, the wires make heat and can cause fires if they touch something they shouldn’t. Last but not least, knob and tube wiring don’t have a ground wire like modern wires do. That means there’s only a hot wire and a return wire. It’s not as safe as the wires we use now, called tar-covered cloth wires. This is especially important to know if you live in Philadelphia.

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Electrical Inspection

Our team of electricians stands out in conducting knob and tube inspections. Equipped with specialized training, we excel in identifying this outdated wiring system in older homes. The Philadelphia region, known for its historical renovations and alterations, presents unique challenges when it comes to uncovering these electrical concerns. That’s why it is highly recommended that you have a qualified electrician examine your electrical system. Additionally, it is crucial to ensure that you engage the services of a knowledgeable electrician when dealing with older wiring.

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