Title 24 Testing in Los Angeles County

One county, three kinds of building departments

Los Angeles County has 88 incorporated cities plus a large unincorporated territory, and the single most common permitting mistake we see is sending an application to the wrong jurisdiction. The rule: the project address — not the mailing city — determines the authority having jurisdiction (AHJ). In LA County that lands you in one of three systems.

1. Inside the City of Los Angeles — LADBS

Department: Los Angeles Department of Building and Safety (LADBS)
Main office: 201 N. Figueroa Street, Los Angeles, CA 90012 (Metro Development Services Center)
Phone: (213) 473-3231 or 3-1-1
Submission methods: PermitLA for express permits (simple scopes with no plan check — most HVAC change-outs, water heaters, electrical service upgrades) and ePlanLA for anything that needs plan review. Both require an Angeleno account.

Most of the residential HERS work we do in the City of LA rides on express permits, which contractors can pull online in minutes. The slow part is closeout — coordinating the LADBS inspector, the homeowner, and the registered CF3R — and that is exactly the part we run for you.

2. Unincorporated communities — LA County Building and Safety

Department: Building and Safety Division, Los Angeles County Public Works
Headquarters: 900 S. Fremont Avenue, Alhambra, CA 91803
Submission methods: EPIC-LA, the county’s online permitting system, plus 10 district offices serving the unincorporated communities
Covers: unincorporated areas such as Altadena, East Los Angeles, Marina del Rey, Hacienda Heights, and Rowland Heights — and 16 smaller cities that contract with the county for building and safety services

If your parcel is unincorporated, permits and inspection scheduling run through EPIC-LA rather than a city portal. The county’s district-office structure means inspector availability varies by area; we book the final inspection and the HERS / ECC test so they land in the right order.

3. The other 87 incorporated cities

Most LA County cities run their own building departments with their own portals, counter hours, plan checkers, and inspector pools. Long Beach Development Services works out of 411 W. Ocean Boulevard; Torrance Community Development out of 3031 Torrance Boulevard; Lakewood out of 5050 Clark Avenue; Carson out of 701 E. Carson Street. A handful of smaller cities contract those services back to the county. We track submittal methods and turnaround quirks city by city — see the city pages below for specifics.

Five climate zones in one county

Los Angeles County spans five of California’s 16 building climate zones — more than any other county we work in. The zone is assigned by the California Energy Commission (CEC) based on the project address (see the CEC climate zone tool), and it decides which prescriptive Title 24 measures and which HERS / ECC verifications your project carries:

Climate Zone 6 — the coast: Santa Monica, Malibu, Redondo Beach, Torrance (western zips), San Pedro, and parts of Long Beach.
Climate Zone 8 — the LA basin and gateway cities: Lakewood, Carson (eastern zips), Downey, Compton, Cerritos, Bellflower, Gardena, and parts of Long Beach and Torrance.
Climate Zone 9 — the valleys and foothills: most of the City of LA including the San Fernando Valley, plus Glendale, Burbank, Pasadena, and Whittier.
Climate Zone 14 — the Antelope Valley high desert: Lancaster, Palmdale, Acton, Llano.
Climate Zone 16 — the high mountain communities, such as Valyermo.

Why it matters: under the 2025 Building Energy Efficiency Standards (in effect for permit applications filed on or after January 1, 2026), refrigerant charge verification is prescriptively required for air conditioners in Climate Zones 8–15 — so an AC change-out in Lakewood or Lancaster carries a verification that the same job in coastal Santa Monica may not. Heat pumps require refrigerant charge verification in all zones under the 2025 code, per the CEC’s What’s New for 2025 fact sheet. We confirm the exact zone and measure list for your address before quoting.

Where we work most in Los Angeles County

Of the 5,300+ permits in our internal records since 2022, the City of Los Angeles is our single highest-volume jurisdiction (579 permits, led by Mid-City, Sylmar, and Highland Park zips) and Long Beach is second company-wide (486). The South Bay and gateway cities — Torrance, Carson, Lakewood, Redondo Beach — plus Whittier round out our heaviest LA County routes. Deep-dive pages for each:

Los Angeles — LADBS territory, 579 permits in our records, from the Valley to the Westside.
Long Beach — our #2 city company-wide; East Long Beach (90815, 90808) dominates.
Torrance — split between coastal CZ 6 and inland CZ 8.
Lakewood — steady tract-home HVAC and ADU volume in CZ 8.
Redondo Beach — our home base, coastal CZ 6.
Carson — email and portal submittals to the city’s Building & Safety.
Whittier — foothill CZ 9, online portal submittals.

What we do across the county

Title 24 HERS / ECC Rating testing — duct leakage, refrigerant charge, cooling coil airflow, fan efficacy, blower door. CF1R / CF2R / CF3R prepared and registered with CHEERS, at no additional charge.
Permit expediting — mechanical, electrical, plumbing. PermitLA, EPIC-LA, or any of the 80+ city portals — whichever your address requires. Plan-check corrections handled.
Final inspections & closeout — we schedule the final with the right inspector pool (LADBS district, county district office, or city), brief the homeowner, and hand off the HERS test and permit packet so the permit actually closes.

Frequently asked — Los Angeles County

Who issues the building permit for my project in Los Angeles County?

It depends on the address, not the mailing city. Inside the City of Los Angeles, permits come from LADBS through PermitLA (express permits) or ePlanLA (plan-check projects). In the other 87 incorporated cities, the city’s own building department issues the permit — Long Beach, Torrance, Lakewood, Carson, and Whittier all run their own counters. In unincorporated communities — Altadena, East Los Angeles, Marina del Rey, and dozens more — the permit comes from LA County Building and Safety through the EPIC-LA portal. We confirm the jurisdiction from the project address before we quote, so the application goes to the right counter the first time.

When does Title 24 require HERS / ECC testing in Los Angeles County?

Whenever permitted work touches energy systems, which covers most projects. HVAC alterations — replacing a coil, condenser, furnace, or more than 40 feet of ducting — typically require duct leakage testing, and in Climate Zones 8, 9, and 14 refrigerant charge verification as well. New construction and ADUs almost always require multiple HERS measures, including QII on most plans. Window replacements, insulation upgrades, and water-heater swaps may trigger HERS depending on scope. Your building department’s plan check will list the required measures on the CF1R; we can also confirm before you submit.

Does the 2025 Energy Code apply to my Los Angeles County project?

Only if the permit application was filed on or after January 1, 2026. The California Energy Commission’s rule is date-of-application: projects applied for before that date stay on the 2022 code even if construction runs into 2026 and beyond. The 2025 code makes heat pumps the prescriptive baseline for space heating in every climate zone and requires refrigerant charge verification on heat pumps statewide, so post-2026 applications in LA County usually carry more field verification, not less.

How fast can ERE schedule a HERS test in Los Angeles County?

Same-day field results in your inbox the day of the test, with the CF3R registered with CHEERS. Our office is in Redondo Beach, so Los Angeles County is home turf — the South Bay, the LA basin, the San Fernando Valley, and the gateway cities are on our daily routes, and we can usually slot a test within 2 to 5 business days.

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Title 24 HERS Testing & Permits Across Los Angeles County