OC Home Projects That Need a Permit

Every Orange County city runs its own building department, so there is no single county-wide list of what needs a permit. The basics are similar everywhere, though, and knowing them can save you from a stop-work notice, a failed inspection, or a surprise when you sell.

A useful rule of thumb: if the project changes the structure, the roof, or the plumbing, electrical, gas, or heating and cooling systems, plan on a permit. Cosmetic work usually does not need one.

Katherine covers the highlights in about a minute in her Short on which renovations require permits; the rest of this page goes project by project.

Why permits matter when you sell

California sellers of one-to-four-unit homes complete a Transfer Disclosure Statement, and it asks whether any additions or alterations were made without the required permits. Unpermitted work does not have to kill a sale, but it can come up in the buyer's inspection, in the appraisal, or when the buyer's insurance company looks at the house. It then becomes one more item in the negotiation, along with the buyer repair requests that typically follow an inspection.

If you are thinking about selling, check the permit history of any past work first. It is much easier to sort out before the home is listed. See also which improvements are worth making before you sell.

Projects that usually need a permit

Water heater replacement. It surprises many homeowners, but gas and electric water heater swaps generally need a permit. Huntington Beach's exempt-work list carves them out by name, and Irvine and Anaheim list water heater replacement as permit work.
Furnace and air conditioner replacement. Irvine lists furnace and A/C replacement as permit work, and a brand-new A/C unit is listed separately. Your HVAC contractor should pull the permit.
Re-roofing. Huntington Beach exempts only re-roofing of an area under 100 square feet, which means a typical full re-roof needs a permit. Costa Mesa's issued-permit records show full re-roofs being permitted too.
Patio covers. Irvine requires a permit for a patio cover regardless of size, and Huntington Beach's guidance lists patio covers as permit work.
Additions, garage conversions, and new rooms. Adding square footage, converting a garage, or adding a bedroom or bathroom all need permits, along with the plumbing and electrical work inside.
Moving or removing walls. Any wall that might be load-bearing should be reviewed before it is touched.
Electrical service and new circuits. Panel upgrades, new circuits, and rewiring need an electrical permit. Replacing a switch or an outlet in the same place generally does not.
Plumbing changes. Re-piping, relocating fixtures, or replacing a concealed drain or supply pipe is new work, not a repair.
Solar panels and batteries. These need a permit, but the process has been streamlined. State law (SB 379) required larger cities and counties to adopt the SolarAPP+ online system for standard residential solar, which can issue a permit in real time for qualifying systems, and the County of Orange has adopted it. Ask your installer how your city handles it.
Accessory dwelling units (ADUs). Permits are required, and state law sets review timelines and limits what cities can ask for. Rules have been changing, so check the city's current ADU page.
Taller fences, walls, decks, and retaining walls. See the thresholds in the next section.

Projects that usually do not need a permit

Exemptions are narrow and they come with conditions. These examples come from the published lists of Irvine and Huntington Beach.

Painting, flooring, cabinets, and countertops. Finish work is exempt.
Replacing windows and doors like-for-like. In Irvine, the replacement must have the same dimensions and not change the frame or the opening. In Huntington Beach, the waterproofing membrane must not be altered and the emergency exit dimensions must be equal to or better than the original. Energy-efficiency and safety rules still apply.
Small sheds and playhouses. A one-story shed up to 120 square feet is exempt from a building permit in both cities, but it still has to meet zoning setbacks and height limits.
Fences. Irvine exempts fences up to 7 feet, with zoning height limits still applying. Huntington Beach exempts masonry or concrete fences up to 42 inches and other fences up to 6 feet, as long as they are not in a required setback or subject to Fire Department review.
Low decks and walkways. Both cities exempt decks, platforms, walks, and driveways up to 30 inches above grade.
Retaining walls up to 4 feet, measured from the bottom of the footing to the top of the wall, unless they hold up extra weight such as a driveway or a structure.
Like-for-like plumbing repairs. Fixing a leak, clearing a drain, or replacing a faucet, toilet, or sink in the same spot does not need a permit in either city, but water heaters are the exception. They do.

Exempt from a building permit does not mean exempt from everything else. Zoning setbacks and height limits still apply, and exempt work still has to meet the code.

Other approvals besides the building permit

Your HOA. Irvine's own guidance reminds homeowners that an association may have its own approval process, and many Orange County communities do. Check your CC&Rs before starting.
Planning and zoning. Setbacks, height limits, lot coverage, and front-yard fence rules are separate from the building code.
Special areas. Huntington Beach's list says that work in a floodplain overlay, an environmentally sensitive area, or something needing discretionary planning approval is not exempt. Homes near the coast may also need coastal approvals.

Hiring a contractor

California requires a contractor's license for any project that needs a building permit, uses additional workers, or costs $1,000 or more in labor and materials. A job cannot be split into smaller pieces to stay under that number.

Check the contractor's license on the Contractors State License Board website before signing.
Ask who is pulling the permit. A contractor who tells you a permit is not needed for work that clearly needs one is a red flag.
Ask for the permit number, and keep the final inspection sign-off with your home records. It is the paper a future buyer's agent will ask for.

If you already have unpermitted work

It happens often, especially with garage conversions, patio covers, and bathrooms added before you bought. If you are a buyer, ask for the permit history early and have the inspector look at any addition or conversion. If you are a seller, you have a few options.

Pull a permit after the fact. Most cities have a process, and it may involve opening up walls for inspection and paying fees. Ask the building division what they would require.
Disclose it and price accordingly. Sellers must disclose known unpermitted work. Selling as-is does not remove that duty.
Remove it. Sometimes taking an unpermitted structure back out is simpler than legalizing it.

Talk with your agent and, if the stakes are large, a real estate attorney, before deciding.

A quick checklist before you start

Does the project touch structure, roof, plumbing, electrical, gas, or heating and cooling? If yes, assume a permit.
Call or check your city's building division and ask. It is free and it is the answer that counts.
Check your HOA's rules and your zoning setbacks.
Hire a licensed contractor and get the permit number in writing.
Keep the final inspection record with your home file.

Building divisions in the cities Katherine works in: Huntington Beach, (714) 536-5241; Irvine, (949) 724-6313; Costa Mesa, (714) 754-5273. Newport Beach and the rest of the county each have their own. For local context, see the guides for Huntington Beach, Irvine, Costa Mesa, and Newport Beach. If you are planning a project before you sell or evaluating a home with past work, reach out — Katherine is happy to help.

Sources

Disclaimer: General educational information, not legal advice or a code interpretation. Permit rules differ by city, change over time, and depend on the details of your project and property. Huntington Beach amended its permit-exemption code in December 2025, so its current list may differ from the 2020 form cited here. Confirm with your city's building division before you start work, and consult a real estate attorney about disclosure questions.

Which Home Improvements Need a Permit in Orange County?