House rewiring in Southern California

Three kinds of old wiring

Not every old house needs a rewire. The usual reasons come down to what is inside the walls.

Wiring	Found in	Main problem	Page
Knob-and-tube	Many homes before about 1950	No ground, old insulation, cannot be buried in insulation	Knob-and-tube replacement
Aluminum branch wiring	Homes from about 1965 to the mid 1970s	Failing connections that overheat	Aluminum wiring
Worn or overloaded copper	Any age	Brittle insulation, damaged cable, added load	Partial rewire

The older-panel pages cover the details. If the whole system is tired, a whole-house rewire is the fix.

Whole house or only part

A whole-house rewire replaces all branch circuits and usually the panel with it. A partial rewire replaces specific runs. Cost, disruption and risk differ.

• Partial rewire. Good for a kitchen remodel, a bad run in the attic, or the circuits that failed an inspection. Typical range is $3,000 to $8,000 as an estimate.
• Whole house. Choose it when old wiring is everywhere, when a panel replacement is already planned, or when the house will be opened up for a remodel. Published cost guides put whole-house rewiring at roughly $7,200 to $20,000 (Fixr and Bob Vila), and the SoCal range for homes of about 1,500 to 2,500 square feet is $8,000 to $20,000 as of October 2026. The whole-house rewire cost page lists the typical range.

Patching drywall or plaster and painting are usually extra, and in a plaster home they add real money. Ask who pays for them before you compare bids.

What an electrician checks first

1. Open a few boxes and read the cable markings.
2. Check the panel brand, rating and condition.
3. Look at the attic and crawl space for cloth cable or knob-and-tube.
4. Test grounds and GFCI protection.
5. Ask about insurance, because some carriers act on what they find.

On older homes the panel often needs work too.

Permit and inspection

Rewiring needs an electrical permit in California cities. The city inspects the rough-in before walls close, then does a final. New circuits must meet the current code, including GFCI and arc-fault protection in the places the code lists. That is part of why rewires cost more than the cable alone. For general permit information, see electrical permits in Southern California.

Selling or buying an older house

A rewire often comes up in a sale, either from a buyer’s inspection or from insurance. The home sale electrical inspection guide explains what inspectors flag. Replacing wiring before listing can be cheaper than negotiating it later, but the order of repairs is worth a conversation with the electrician.

How to compare bids

• The number of circuits and outlets, written out
• Whether the panel is included
• Whether patching and paint are included
• Permit and inspection lines
• Whether smoke and CO detectors are in scope, if your city asks for them

Request quotes with photos of the panel, the attic and one or two outlets.

How long it takes

A partial job can finish in a few days. A whole house usually takes more than a week, plus time for the two city inspections. Plan for sections of the house to be without power for part of a day. Move valuables from the attic hatch and clear a path to the panel before the crew arrives.

Signs worth acting on now

Some symptoms should not wait for a remodel. Outlets or switch plates that are warm to the touch, a burning plastic smell, buzzing in a wall, scorch marks and breakers that trip again right after a reset all point to a problem inside the wiring. Turn off the circuit and have it looked at. The repairs pages on hot or burning-smell outlets explain what to do while you wait.

What homeowners often get wrong

Many owners assume a rewire means gutting the house. Most of the work happens in attics and crawl spaces. Others assume a new panel fixes old wiring. It does not, because the problem is in the branch circuits. A third mistake is comparing bids that cover different scopes, which is why a written list of circuits, devices and patching responsibilities matters more than the total at the bottom.