Earthquake retrofit in Orange County

Which houses need a retrofit?

Houses raised on a foundation, with a crawl space under the floor. The California Earthquake Authority says older houses with steps up to the first floor can shift off their foundations in an earthquake. A house on a concrete slab is not the kind this retrofit is for.

The state's Earthquake Brace + Bolt program is more exact. Its 2026 rules cover detached houses of one to four units, built before 1980, on level ground or a low slope, with a continuous raised perimeter foundation. Mobile and manufactured homes do not qualify.

To check your own house, look in the crawl space for bolts or steel plates tying the wood sill to the concrete, and for short wood-framed walls between the foundation and the floor. Those are cripple walls, and they are what the bracing is for.

What does a bolt and brace retrofit involve?

Two things. Anchor bolts or foundation plates fasten the wood frame to the concrete foundation. Where there are cripple walls, plywood or OSB sheathing is attached along them to stiffen them. A house whose frame sits directly on the foundation gets bolting only.

The standard is Chapter A3 of the California Existing Building Code. Under the program rules, cripple walls up to 4 feet tall can be done from a standard plan set. Taller cripple walls (up to 7 feet), a house partly on a slab, or more than three stories need plans from a licensed design professional.

Cost: the program's 2026 rules say a typical Chapter A3 retrofit costs between $3,000 and $7,000, depending on the location and size of the house, contractor fees and materials. That is a statewide program figure, not an Orange County survey.

Two smaller earthquake items. State law requires every residential water heater to be braced, anchored or strapped; our water heater guide covers it. And SoCalGas says not to shut off the gas meter after a quake unless you smell gas, hear it escaping or see other signs of a leak, and never to turn it back on yourself. Our new homeowner checklist covers the meter and automatic shutoff valves.

How does the Earthquake Brace + Bolt grant work?

The program, run by the California Residential Mitigation Program, pays up to $3,000 toward a code-compliant retrofit. Households with an annual income of $94,480 or less can also get a supplemental grant of up to $7,000, as funding permits.

Registration opens for a limited time each year, by ZIP code. When we checked on September 26, 2026, the program's ZIP lookup included many Orange County ZIP codes, among them ones in Anaheim, Santa Ana, Irvine, Huntington Beach and San Clemente, and showed registration as closed. Check your ZIP code on the program's ZIP code page and sign up there for word of the next window.

The order matters. The rules say the permit must be issued after you are accepted, and work started before the program approves it makes the house ineligible. The contractor must hold a general building license (Class A or B, not B-2), or you can do the work yourself. A parcel that has already received an earthquake retrofit grant cannot get another.

Does a retrofit lower earthquake insurance?

On a California Earthquake Authority policy, it can. Once the house is bolted, its cripple walls are braced where they exist and its water heater is secured, the CEA offers a premium discount of up to 20% for a retrofitted home built 1940 to 1979, and up to 25% for one built 1939 or earlier. Your insurer needs the CEA's Dwelling Retrofit Verification form signed by a contractor or structural engineer, or a Brace + Bolt verification number.

Do I need a permit, and will it raise my property tax?

Plan on a building permit. The grant program requires one for the retrofit alone, with any other work on a separate permit, and a copy signed by the inspector after the final. Our Orange County permit guide covers how cities differ.

The retrofit itself should not raise your assessed value. California Revenue and Taxation Code section 74.5 says seismic retrofitting is not new construction for reassessment. To claim that, tell the county assessor before, or within 30 days of, finishing the project, and file the supporting documents within six months of finishing.

City pages: Anaheim, Santa Ana, Irvine, Huntington Beach and San Clemente, or every city on the Orange County hub.

As of September 2026. Grant rules, ZIP codes and discounts change; the program and your insurer have the final word.