Many home buyers ask us if they can buy a house with knob and tube wiring or if they should get it replaced first. It’s important for home buyers to understand that knob and tube wiring itself is not unsafe. In fact, the necessary drilling, soldering, wrapping, and splicing during the original installation required great deal of skill, since the wiring was meant to last. However, home buyers may have a problem getting insurance for a home with knob and tube wiring.
What is Knob and Tube Wiring?
Homes in the U.S. built from around 1880 to the 1940s often still have knob and tube electrical wiring. This is where electrical wires anchored by ceramic insulating knobs pass through tubes placed inside holes drilled in the joists of the house.
Here are pictures of what knob and tube wiring looks like in the home:
Some Issues with Knob and Tube Wiring
When you are buying a home with knob and tube wiring, there are a few issues to be aware of. For instance, insulation cannot touch the wires, as the heat from the wires cannot dissipate. Knob and tube wiring also does not provide a third wire for grounding. Even if two-slot outlets are replaced with three prong outlets (for devices that require them, such as kitchen appliances) there is still no third wire which protects against electric shock. One of the most common issues with knob and tube wiring is with incorrect modifications. Because it is easily accessible, some homeowners make their own repairs and do not splice the wire correctly or they make inadequate, unsafe modifications. Always hire a licensed electrician to make changes or updates to knob and tube wiring.
Knob and tube wiring is no longer used in homes because it doesn’t carry the same capacity for electricity that modern homes require. Modern households tend to use much higher loads of electricity than the wiring was originally designed for (usually 60 amps). Homeowners should not install higher amp fuses to match the increase in electricity use as this will cause the wires to overheat.
Financing a Home with Knob and Tube Wiring
The Department of Housing and Urban Development (HUD) states that home appraisers should examine the electrical box to ensure there are no broken or frayed wires. They don’t usually examine whether the home has knob and tube wiring.
Getting Insurance for a Home with Knob and Tube Wiring
Though you may be able to get financing for a home with knob and tube wiring, getting insurance for it can be difficult and the cost will likely be more than double. If the knob and tube wiring is active, most insurance companies will require that it be removed prior to closing or 30 days after closing.
If the system is inactive, an insurance company might agree to write a policy. The company may either require that the wiring be removed first or in some cases will allow from 30 to 60 days after policy inception to have it professionally removed. If the home buyers can’t take it out, or are unable to do it within a certain time frame, or if it is active, they can still get insurance through the Massachusetts Property Insurance Underwriting Association (MPIUA). The MPIUA provides basic property insurance on eligible property for applicants who have been unable to gain insurance through the voluntary market. Keep in mind rates for MPIUA tend to be higher (between 30-60%) higher than a standard insurance company in Massachusetts.
When buying a home with knob and tube wiring you should have a licensed electrician look the system over to determine the overall condition of the wiring. Any circuits that has been modified, damaged, or covered with insulation should be replaced.