Over the years, there have been a lot of changes in how electrical systems are made. If you have an older home, there’s a chance you have an older style of wiring called knob-and-tube wiring. This outdated wiring can still function fine, but it comes with some potential dangers. Depending on your case, it might be smart to go ahead and replace this wiring even if it isn’t breaking yet.

What’s Knob-and-Tube Wiring?

Knob-and-tube wiring is a unique type of wiring that was often used in houses constructed between 1880 and 1940. This wiring consists of copper wires that run through porcelain tubes and wrap around porcelain knobs. The copper transmits a current, while the porcelain helps to insulate it.

Knob-and-tube wiring often runs through the lumber framing of a house instead of dangling loosely inside walls or ceilings. When the wiring connects to a light fixture, switch, or outlet, the connection is insulated with rubber, asbestos cloth, or another material. Unlike modern wiring, knob-and-tube wiring only has a hot and neutral wire, not a ground wire.

Can You Still Use Knob-and-Tube Wiring?

If your knob-and-tube wiring is properly installed and maintained, it can last almost indefinitely. The porcelain and copper components are extremely sturdy, so there are a lot of Victorian homes that still run on the house’s original electrical grid. As long as it’s insulated correctly, using an old knob-and-tube system doesn’t mean your home is likely to burn down.

This type of wiring also comes with some other perks. Since the installation method keeps your wiring away from the surface framing inside your walls, knob-and-tube wires are also less likely to be punctured by nails while you hang shelving or photos. Knob-and-tube wiring has a higher ampacity than modern systems of a similar gauge, so they can easily handle powerful modern electronics.

Ways Knob-and-Tube Wiring Can Malfunction

Despite being safe in many situations, knob-and-tube wiring is no longer used for many reasons. First of all, it has no ground wiring. This makes it incompatible with a lot of modern electronic appliances that use a three-prong plug. Furthermore, it can potentially shock people when they use the appliance. The other big safety issue is that knob-and-tube wiring isn’t moisture safe. Especially in kitchens and bathrooms, it can pose a major shock hazard.

Another problem to be aware of is that knob-and-tube wiring isn’t compatible with modern insulation. It’s designed to dispel excess heat into the hollow space between walls. If you add insulation to weatherproof your home, it can trap heat around the wiring. In some cases, this can lead to electrical fires.

The final issue to be aware of is simply that knob-and-tube wiring is usually very old. Since it’s no longer used, if your home has it, it’s probably been around for decades. All this time gives your electrical system many chances to go wrong. Many old houses have DIY modifications where inexperienced electricians messed around with the knob-and-tube wiring. This can lead to both shocks and fires. In some cases, the wiring’s age means it has had time to get damaged. If home construction has cracked any tubes, your wires might not be well-insulated. Knob-and-tube wiring that used rubber as insulation is especially likely to cause fires. Over time, rubber dries out and cracks, so fixtures connected to the wiring might not be properly insulated anymore.

Should You Replace Your Knob-and-Tube Wiring?

Whether or not you should keep your wiring depends on your electrical needs and the condition of the knob-and-tube system. If it’s in good shape, knob-and-tube might be fine to keep around in most of your home. However, to stay safe, you’ll need to replace it in any areas with moisture, areas you want to insulate walls, or rooms where you want to use modern appliances.

At Dawson's Electric, we have plenty of experience helping Fuquay-Varina residents with historic homes. Our team can assess your knob-and-tube system and help you decide if it’s still safe to use. We can also remove it and install a modern electrical system if that’s what you prefer. Our team provides a variety of other modern electrical services as well, including electrical fixture installation, electrical repair, and whole-home generator installations. To learn more about our services, give Dawson's Electric a call today.

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