In short
- 242 ADU permits on record, nearly all since 2019.
- 59 in 2025, up 55% from 2024.
- Typical permit time: 151 days from application to permit (median of 134 permits with both dates recorded).
About this data
- Source: California HCD Housing Element Annual Progress Reports. The state data does not say whether an ADU is detached, attached, a garage conversion or a JADU, so most records show as 'unknown'. Permit valuations are not published in this source. Timelines use the application date the city reported to the state, matched to the permit where possible; some cities report their planning application date, so timelines can include planning review. Each project is counted once, in its building-permit year (or completion year when no permit date was reported).
Permits by year
Permits by year and type (table)
| Year | All ADU permits | Garage conversions | Detached |
|---|---|---|---|
| 2018 | 3 | — | — |
| 2019 | 13 | — | — |
| 2020 | 20 | — | — |
| 2021 | 26 | — | — |
| 2022 | 41 | 0 | 0 |
| 2023 | 42 | — | — |
| 2024 | 38 | — | — |
| 2025 | 59 | 0 | 0 |
“—” means the source for that year does not report ADU type.
Read more: ADU types explained
Not counted above: 35 approved projects with no building permit reported yet.
ADU rules in Imperial Beach
State law check: HCD sent a technical-assistance letter (February 27, 2026) noting the city's ordinance on file, from 2022, may be outdated; no formal findings.
| Rule | Imperial Beach's code | State law guarantees |
|---|---|---|
| Maximum size | Detached: 1,200 sq ft. Attached: 50% of the house, up to 800 sq ft. Conversion of existing space: 1,200 sq ft. Junior ADU 500 sq ft. | At least 850 sq ft (1,000 sq ft with 2+ bedrooms) must be allowed; an 800 sq ft detached ADU always is. Conversions of existing space have no size cap. Junior ADU: up to 500 sq ft. |
| Height | Detached: 16 ft (18 ft within ½ mile of transit, plus 2 ft for a matching roof pitch). Attached: 25 ft or the zone limit, whichever is lower. | Detached: at least 16 ft (18 ft within ½ mile of transit, plus 2 ft for a matching roof). Attached: 25 ft or the zone's limit, whichever is lower. |
| Setbacks | 4 ft side and rear. | No more than 4 ft side and rear; none for conversions of existing space. |
| Parking | Not stated on the city's ADU page. | At most 1 space; none within ½ mile of transit and in several other cases. No replacement parking when a garage is converted. |
| Owner living on site | Not stated on the city's ADU page. | None for ADUs. A junior ADU that shares a bathroom with the house requires the owner to live in one of them. |
| How many on a single-family lot | Single-family zones: one new detached ADU, one attached or converted ADU (not both) and one junior ADU. | One ADU converted from existing space, one junior ADU and one new detached ADU (up to 800 sq ft). From January 1, 2027: two new detached ADUs (a city then needn't allow a junior ADU on that lot). |
| Short-term rentals | Not stated on the city's ADU page. | No guarantee: cities may require rentals of more than 30 days, and junior ADUs can't be short-term rentals. |
- Coastal Zone: new ADUs, conversions of garages or storage, and garage-to-junior-ADU conversions need a coastal permit first ($1,000, about 30 days); some areas are under Coastal Commission jurisdiction instead of the city's.
- The city has pre-approved ADU plans.
- The online municipal code doesn't include the city's ADU rules; the standards above are from the city's ADU page.
Where local rules conflict with state law, state law controls. Sources: City of Imperial Beach ADU page · Imperial Beach coastal permit handout for ADUs · HCD letter (February 27, 2026); HCD's list of review letters; California ADU rules. Verified Oct 5, 2026. Rules change and every lot is different: confirm with the city before you design.
How long permits take
| Type | Median days, application to permit | Middle half | Permits |
|---|---|---|---|
| Junior ADU (JADU) | too few to say | 3 | |
| Unclassified | 150 | 91 – 195 | 131 |
Middle half: the range covering the middle 50% of permits (a quarter were lower, a quarter higher).
Read more: How long ADUs take to build
What neighbors declared as cost
Cost data (declared permit valuations) is not published for this area in these sources.
Read more: How to choose an ADU builder
An ADU builder serving Imperial Beach? Feature your business on this page.
Questions about ADUs in Imperial Beach
How many ADUs have been permitted in Imperial Beach?
Public records show 242 ADU permits in Imperial Beach through 2025, nearly all since 2019. 59 in 2025, up 55% from 2024. These counts come from the city's reports to the state, which place a project in its completion year when no permit date was reported.
How long does an ADU permit take in Imperial Beach?
Among the 134 ADU permits in Imperial Beach with both dates recorded, half were issued within 151 days of the application; the middle half took 91 to 196 days. That includes plan-check corrections and resubmittals, not just the review itself.
Can I build an ADU on my property in Imperial Beach?
California law allows ADUs on most lots with a house, including in Imperial Beach, but what you can build depends on your lot, local rules and utilities. This site shows permits, not eligibility. See California ADU rules.
Where do I apply for an ADU permit in Imperial Beach?
Apply with the City of Imperial Beach's Community Development Department; ADUs in the Coastal Zone need a coastal permit first, through the city's online portal. Official ADU page.
How current is this?
- State annual progress reports: through 2025 (published once a year)
How our data works · Download the data · Free to reuse with credit to SoCal ADU Tracker (socaladutracker.com), under CC BY 4.0.