What's the same in every LA County city
California state law sets a floor no city can go below: ministerial (no-hearing) review, a 60-day decision clock on complete applications, at least an 800 sq ft ADU with 4-foot side and rear setbacks, and size minimums of 850 sq ft (studio/1-bed) or 1,000 sq ft (2+ bed) that local caps can't undercut. Our California ADU laws guide covers the statewide framework, and the size & setback calculator shows the exact floors for your ADU type.
Everything beyond that floor is local — and that's where LA County cities genuinely differ.
Where LA County cities differ
Highlights from our city research — each links to the full city guide with sources and details:
| City | What stands out |
|---|---|
| Glendale | Standard ADU Plan Program with designer-owned pre-approved plans; on historic properties, exterior ADU changes generally can't be visible from the public street. |
| Burbank | BPAP pre-approved plan library, a match-the-main-house exterior design rule, and plan check by the city's own utility (BWP). |
| Pasadena | Standard Plans catalog plus real fee reductions — roughly 25% for most ADUs, over 50% with standard plans or a housing agreement, per the city. |
| Long Beach | Runs its own Pre-Approved ADU Program — city-reviewed plans that can shorten design and permitting for homeowners who use them. |
| Redondo Beach | An AB 2533 program to legalize older unpermitted ADUs, an AB 1332 pathway, and Coastal Zone review near the water. |
| Santa Monica | Preapproved Standard ADU Plan program (AB 1332, detached-only), ministerial approval, a 6-foot separation from the main house, and Coastal Zone review near the water. |
| Santa Clarita | Requires solar on new detached ADUs, an architectural-match rule (same colors/materials, 2:12 roof), and up to 25 ft for attached units — with Planning clearance before Building & Safety. |
| Inglewood | One of the few cities with a Rent Ordinance (with a published ADU chart), a detailed design-match rule (roof pitch, window casing, color), and a recorded no-sale/no-short-term-rental covenant. |
| El Monte | Caps detached ADUs at the same 850/1,000 sq ft as attached (not 1,200), requires the main home to be finaled at or before the ADU on new builds, and requires solar on new detached units. |
| Alhambra | An ADU of 800 sq ft or less with 4-ft setbacks is exempt from the underlying zone's floor-area, lot-coverage, and open-space limits — a big deal on tight San Gabriel Valley lots. |
| Torrance | Offers pre-approved ADU designs and has specific Coastal Commission requirements for properties near the beach. |
| Downey | Runs a pre-approved standard plans program for detached ADUs. |
| Whittier | Offers preapproved ADU plans, currently limited to one-story detached structures. |
| Bell Gardens | PADUPP — the city's Preapproved Accessory Dwelling Unit Plans Program — offers city-vetted designs. |
| Norwalk | Allows ADUs up to 18 feet near transit or an existing two-story home — taller than the standard 16-foot state floor. |
| La Mirada | Local code technically prohibits Junior ADUs — but state law overrides that and requires the city to allow them. |
| Artesia | California HCD flagged the city's local ADU ordinance as not fully compliant with state law in a late-2024 review — state law is the safer reference point. |
| Signal Hill | Has no separate local ADU ordinance at all — it follows California state ADU law directly. |
All 24 Los Angeles County city guides
Before you start in any LA County city
- Confirm your jurisdiction. Some addresses are unincorporated county, not the city they share a name with — different rules apply. Our zoning lookup guide shows how to check.
- Check for a pre-approved plan program. Where one exists, it can meaningfully shorten design and permitting — see the table above for cities that offer one, and our statewide pre-approved plans guide for how the AB 1332 pathway works.
- Ask about fees below 750 sq ft. Development impact fees are exempt at 750 sq ft or less statewide — our fee guide has the thresholds.
- Get the local answer in writing. City counter staff answers vary; the municipal code and your permit record are what count.
How this page is built: every city-specific claim above is drawn from our individual city guides, each researched from that city's official planning resources and municipal code, with state-law context from the California HCD ADU framework. City programs and ordinances change — the linked city guide is always the more detailed reference, and your city's planning department is the final authority. This page is general information, not legal advice, and doesn't guarantee what your specific property qualifies for. See also our Inland Empire ADU guide.