Knob and Tube Wiring in California Homes: Should You Replace It?

Knob and tube wiring was standard until about 1950 and thousands of homes in Los Angeles, the Bay Area, Sacramento and San Diego still have some. It has no ground, its insulation is brittle, and it must never be buried in attic insulation.

Why insurers care

Many carriers decline coverage or charge more when knob and tube is present. A electrical inspection report is often the first thing they ask for.

Replacement options

A whole house rewire replaces every circuit with grounded copper wiring, adds AFCI and GFCI protection and usually includes a panel upgrade. Partial rewires are possible for kitchens and baths during remodels.

What it costs

Square footage, attic and crawlspace access and the number of circuits drive the price. Most single-story homes take three to five days with the family living in the home.

Not sure what you have? Find your city on the locations page and schedule an inspection.