Same zip, different jurisdiction: this page covers LA County Public Works (DPW). The same zip code(s) also cover parts of Whittier (Whittier (its own permits)). Verify your parcel's jurisdiction before filing — different agencies, different rules.
Gateway Cities · LA County (Unincorporated)
ADU permits in South Whittier
Zip codes:9060390605
South Whittier is an unincorporated community of about 57,000 people in the southeast Gateway Cities region of LA County, surrounded by the cities of Whittier, La Mirada, and Santa Fe Springs. It is not a city. Building permits run through Los Angeles County Public Works (Building & Safety) under LA County Code Title 22, not through Whittier's building department.
Unincorporated LA County, not LADBS
South Whittier is unincorporated territory. Building permits go through LA County Public Works (Building & Safety) ↗ under LA County Code Title 22, not the Los Angeles Department of Building and Safety (LADBS). Our address checker pulls real feasibility data for any LA County address; the South Whittier-specific permit pathway is detailed below.
South Whittier by the numbers
Rounded figures from the 2020 US Census, LA County Assessor parcel data, and LA County DPW permit records.
Population
57,000
2020 Census
Single-family homes
~13,500
LA County Assessor
Median lot size
6,000 sqft
Approximate
ADU permits filed 2025
~112
Source: HCD 2025 total (1,278) distributed proportionally across 2024 per-area shares. 2024: 130.
What makes South Whittier different
South Whittier is functionally distinct from the City of Whittier despite sharing the name. Permits run through LA County DPW Building & Safety at the Alhambra office via EPIC-LA. Mid-tier home values + dense single-family stock support steady long-term rental ADU economics.
LA County ADU rules for South Whittier
Last verified: 2026-04-15
Current LA County rules from Title 22 of the County Code, as applied to South Whittier. State preemption (Gov Code §65852.2) means the county can't reduce below the state baseline. We note where that applies.
| Max detached ADU size | 1,200 sqft (state default) |
| Max ADU height | 16 ft / 18 ft with second-story setbacks |
| Setbacks | 4 ft side / 4 ft rear (state minimum) |
| Permitting agency | LA County Public Works (Building & Safety), Alhambra office NOT Whittier city. EPIC-LA portal for online submission. |
| Local processing time | 60 days from complete submittal (state-mandated) |
Active overlays + extra rules in South Whittier
LA County overlays + state-level designations that hit a meaningful share of South Whittier parcels.
Watch-outs specific to South Whittier
- 01
Don't file with Whittier — file with LA County DPW
South Whittier residents frequently start permits with the City of Whittier's building department, then have to restart with LA County DPW. Verify your parcel's jurisdiction (LA County Assessor parcel lookup) before submitting.
Plans that fit South Whittier lots
For unincorporated Los Angeles County, the LA County A / B / C pre-approved Accessory Dwelling Unit (ADU) plans are free and usable here. California Department of Housing and Community Development (HCD)-approved prefab also bypasses local plan check entirely.
Amenities + civic services in South Whittier
Parks, libraries, and the school district that serve the area. Context that matters for renter appeal, family relocation, and long-term resale.
Parks + sports
Sorensen Park
Sorensen Avenue
LA County Regional Park.
- Baseball
- Playground
- Picnic
- Community Center
Libraries
Sorensen Library
LA County Library
Sorensen Avenue
Public schools
School assignments vary by exact address. Performance levels below are from the official California School Dashboard — California's official accountability system uses colored levels (blue highest, red lowest) rather than 1-10 numeric scores.
District
South Whittier School District (elementary) + Whittier Union High School District
Getting around South Whittier
Car-dependent suburban with Norwalk Transit bus service.
Transit + walkability
Bus lines
- Norwalk Transit
- Foothill Transit
Walkability
Mostly car-dependent.
Nearby airports
Distance + type for each major Los Angeles-area airport reachable from South Whittier. Useful for travel, commute, and any flight-path noise concerns on specific parcels.
Long Beach Daugherty Field (LGB)
~9 miRegional / domestic
Fullerton Municipal (FUL)
~5 miGeneral aviation
Los Angeles International (LAX)
~22 miInternational
Nearby areas to South Whittier
Other Los Angeles-area pages worth a look. Each one runs different Accessory Dwelling Unit (ADU) rules depending on jurisdiction — we show you what changes when you cross a city or county line.
LA County unincorporated
West Whittier-Los Nietos →
Mid-size Gateway Cities unincorporated community. LA County jurisdiction + mid-tier home values shape the Accessory Dwelling Unit (ADU) economics.
LA County unincorporated
East La Mirada →
Small Gateway Cities unincorporated community east of La Mirada. LA County (not La Mirada city) jurisdiction shapes the Accessory Dwelling Unit (ADU) permitting path.
LA County unincorporated
Hacienda Heights →
Eastern SGV unincorporated community with strong Taiwanese-American cultural roots. Large lots + mid-tier home values + LA County jurisdiction (not LADBS) shape the Accessory Dwelling Unit (ADU) calculus.
Other permits in South Whittier
LA County Public Works (Building & Safety) handles ADU, solar, and garage-conversion permits for South Whittierand the rest of unincorporated LA County. We've broken each out as its own pathway page.
Frequently asked questions about South Whittier ADUs
›Can I build an ADU in South Whittier?
Yes. South Whittier allows ADUs under LA County Code Title 22, aligned with California Gov Code §65852.2. Most single-family lots can host one ADU plus one JADU. Permits go through LA County Public Works (Building & Safety), not LADBS, since South Whittier is unincorporated territory rather than a city.
›Why does South Whittier use LA County rules instead of LA City rules?
South Whittier is unincorporated. It's never been formally incorporated as its own city, so LA County serves as the local government. Building permits, zoning, sheriff, libraries (in many cases), and most other services run through county departments rather than city ones.
›Where do I submit my South Whittier ADU permit?
Online via LA County's EPIC-LA portal, or in-person at the LA County Public Works Building & Safety counter in Alhambra (900 S. Fremont Avenue). The EPIC-LA online portal handles most ADU submittals end-to-end, so you rarely need to visit in person.
›How long does the ADU permit process take in South Whittier?
LA County DPW targets the state-required 60-day plan check for ADUs from a complete submittal. Hillside, VHFHSZ, or environmental-review parcels can extend timelines by 4 to 12 weeks. South Whittier-specific overlays may add additional time. See the watch-outs above.
›Are LA County's pre-approved ADU plans free?
Yes. LA County maintains three pre-approved standard ADU plans (Plans A, B, and C) usable in any unincorporated area, including South Whittier. They're free to use, similar to LADBS's YOU-ADU program. The trade-off is reduced design flexibility, but for a fast, low-cost permit path they're the strongest option.
Ready to see what your South Whittier lot can do?
Our free address checker pulls real zoning, overlay, and parcel data for any Los Angeles County address, including unincorporated South Whittier. Start there and we'll surface what applies to your specific lot.
Check your address →Reviewed by Yair Harpaz, Founder, PermitPathLA. California DRE-licensed broker with 30+ years of Los Angeles real estate and mortgage industry experience.
South Whittier ordinance data last reviewed .
See an error or stale rule? corrections@permitpath.la
Primary sources: LA County DPW ADU info · LA County Code Title 22