About this data
- Neighborhood pages cover 2020 onward. Permits here don't record a Neighborhood Council, so this page counts City of Los Angeles ADU permits in ZIP code 90049, which don't match the neighborhood exactly. Build type is classified automatically from permit descriptions.
- Costs are declared permit valuations (single-ADU permits only), not final construction costs.
Permits by year
Permits by year and type (table)
| Year | All ADU permits | Garage conversions | Detached |
|---|---|---|---|
| 2020 | 24 | 8 | 11 |
| 2021 | 46 | 12 | 20 |
| 2022 | 58 | 9 | 30 |
| 2023 | 49 | 4 | 22 |
| 2024 | 51 | 7 | 17 |
| 2025 | 55 | 12 | 21 |
| 2026 so far | 57 | 6 | 17 |
“—” means the source for that year does not report ADU type.
Read more: ADU types explained
Not counted: 7 expired or cancelled permits.
How Brentwood compares
- Brentwood has the 8th-most ADU permits (340) among West Los Angeles neighborhoods (12 on this site).
- Garage conversions are 17% of Brentwood's ADU permits, lower than across West Los Angeles neighborhoods (39%).
- The median time from application to permit here is 180 days, longer than the median across West Los Angeles neighborhoods (168 days).
- The median declared value of a detached ADU here is $85,500, lower than the median across West Los Angeles neighborhoods ($95,000).
ADU rules
Los Angeles' ADU rules apply citywide, with extra rules for hillside, fire-zone and coastal lots: see the rules table.
How long permits take
| Type | Median days, application to permit | Middle half | Permits |
|---|---|---|---|
| Detached ADU | 217 | 146 – 386 | 136 |
| Attached ADU | 179 | 117 – 288 | 105 |
| Garage conversion | 126 | 65 – 185 | 58 |
| Junior ADU (JADU) | 150 | 74 – 187 | 17 |
| Unclassified | 238 | 162 – 380 | 20 |
Middle half: the range covering the middle 50% of permits (a quarter were lower, a quarter higher).
Read more: How long ADU permits take in Los Angeles (and other cities) · How long ADUs take to build
What happened to these permits
Of the 184 ADU permits issued in Brentwood from 2020 through 2023, including ones that later expired or were cancelled, 81% have been signed off by the city as finished. Where the certificate of occupancy date is recorded, it came a median of 19 months after the permit.
| What became of the permit | Share |
|---|---|
| Finished (signed off by the city) | 81% |
| Still open | 15% |
| Expired or cancelled | 4% |
Expired and cancelled permits aren't in this page's totals; they're included here so the table covers every permit issued. A still-open permit may be under construction or stalled.
What neighbors declared as cost
| Type | Median declared value | Middle half | Permits |
|---|---|---|---|
| Detached ADU | $85,500 | $57,250 – $147,000 | 134 |
| Attached ADU | $105,000 | $30,000 – $433,625 | 50 |
| Garage conversion | $50,000 | $30,000 – $98,750 | 54 |
| Junior ADU (JADU) | $50,000 | $41,250 – $116,250 | 14 |
| Unclassified | $69,500 | $23,750 – $115,625 | 16 |
Declared permit valuations often understate real construction cost.
Read more: What ADUs cost in Los Angeles
Read more: How to choose an ADU builder
An ADU builder serving Los Angeles? Feature your business on this page.
Recent ADU permits in Brentwood
- Garage conversion on Bowling Green Way (Oct 2026)
- Junior ADU (JADU) on Saltair Pl (Oct 2026)
- Garage conversion on Granville Ave (Oct 2026)
- Detached ADU on Homewood Road (Oct 2026)
- Attached ADU on Bayliss Road (Oct 2026)
- Attached ADU on Cashmere St (Sep 2026)
Street names only. See each permit on the map.
Questions about ADUs in Brentwood
How many ADUs have been permitted in Brentwood?
The City of Los Angeles issued 340 permits for ADUs in Brentwood from 2020 through Oct 31, 2026, including 58 garage conversions and 138 detached ADUs.
How long does an ADU permit take in Brentwood?
From application to issued permit, the median in Brentwood was 126 days for garage conversions and 217 days for detached ADUs.
How much does an ADU cost in Brentwood?
The median value declared on permits was $50,000 for garage conversions and $85,500 for detached ADUs. Declared permit values often understate the full construction cost, so get several builder quotes.
How long does it take to build an ADU in Brentwood?
Of the 184 ADU permits issued in Brentwood from 2020 through 2023, including ones that later expired or were cancelled, 81% have been signed off by the city as finished. Where the certificate of occupancy date is recorded, it came a median of 19 months after the permit.
Can I build an ADU on my property in Brentwood?
California law allows ADUs on most residential lots with a house, but what you can build depends on your lot, zoning and hillside or fire-zone rules. This site shows permits, not eligibility; check with the Los Angeles Department of Building and Safety or a licensed builder.
How current is this?
- City of Los Angeles permits: through Oct 31, 2026 (published about weekly)
How our data works · Download the data · Free to reuse with credit to SoCal ADU Tracker (socaladutracker.com), under CC BY 4.0.