Get matched with top percolation testing pros in Glennie, MI

Knob and tube wiring is an older type of electrical wiring that's no longer used and generally not considered safe. However, some homes still have it, or may have a knob and tube wiring system that was incorrectly modified or rigged to work with a modern electrical system. Knob and tube wiring may contain asbestos insulation, but the only way to know is to have the material professionally tested.

According to the National Cancer Institute, asbestos-related diseases can take anywhere from 10 to 40 years for symptoms to appear. The health risks increase with prolonged and heavier exposure. Risk factors also include:

• Amount of exposure

• Chemical makeup, size, and shape of the asbestos fibers

• Length of time a person is exposed to asbestos

• Genetic factors 

• Source of exposure (direct exposure or secondhand exposure from someone directly exposed)

Whether or not to buy a home containing asbestos is ultimately a decision for the homebuyer, and there are several things to consider. When in good condition and contained, asbestos is unlikely to present a health risk—it’s when those tiny fibers are loose and airborne that they become a problem. Consider any renovations you plan on doing to the home that could disturb existing asbestos and the cost of removal. If an inspection finds asbestos in a home on the market, you could negotiate with the seller for a lower price, though this isn’t a sure thing.

The Environmental Protection Agency (EPA) banned the use of asbestos pipe insulation in certain applications in 1975. It released further bans in 1989 and 2019. While asbestos pipe insulation was common from the 1930s to 1970s, its use fell off after the 1970s due to public concern and the EPA's actions.