In short
- 62 ADU permits on record, nearly all since 2019.
- 15 in 2025.
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 | 1 | — | — |
| 2019 | 3 | — | — |
| 2020 | 5 | — | — |
| 2021 | 10 | 1 | 2 |
| 2022 | 10 | — | — |
| 2023 | 10 | — | — |
| 2024 | 8 | — | — |
| 2025 | 15 | — | — |
“—” means the source for that year does not report ADU type.
Read more: ADU types explained
ADU rules in Laguna Niguel
State law check: HCD found the January 2025 ordinance noncompliant (November 17, 2025), including its front-setback wording and missing parking exemptions. The city amended it (Ord. 2026-239, February 17, 2026), which addresses those points; we haven't seen HCD's review.
| Rule | Laguna Niguel's code | State law guarantees |
|---|---|---|
| Maximum size | Locally regulated ADU: 850 sq ft (studio or 1 bedroom) or 1,000 sq ft (2+ bedrooms); attached ADUs 50% of the house, but at least 800 sq ft. State-law detached ADU: 800 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 near transit, plus 2 ft for roof pitch; 18 ft with a multistory apartment building). Attached: 25 ft or the zone limit, 2 stories. Other locally regulated ADUs: 1 story. | 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; 20 ft front for locally regulated ADUs (can't block an 800 sq ft ADU). None for rebuilds in the same footprint. | No more than 4 ft side and rear; none for conversions of existing space. |
| Parking | 1 space per ADU or per bedroom, whichever is less, unless exempt; none for state-law ADUs; no replacement parking. | 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 | None for ADUs. Junior ADU: the owner lives on site unless it has its own bathroom; deed restriction. | 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 | A converted ADU and a junior ADU, plus one new detached ADU up to 800 sq ft. | 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 | 30 days or more, for ADUs and junior ADUs. | No guarantee: cities may require rentals of more than 30 days, and junior ADUs can't be short-term rentals. |
- The city's ADU web page says one ADU and one junior ADU per lot, fewer than the code and state law allow.
- The city's submittal checklist (December 2023) asks for homeowners association approval; state guidance says an HOA review can't hold up an ADU permit.
- Locally regulated ADUs must match the house's materials, colors and roof slope, with privacy glass or screening and evergreen landscaping toward the street.
- The city offers free pre-approved ADU plans.
Where local rules conflict with state law, state law controls. Sources: Laguna Niguel Municipal Code 9-1-35.26 · HCD findings (November 17, 2025) · ADU submittal checklist, Form 218 (Dec 2023); 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 |
|---|---|---|---|
| Detached ADU | not reported | ||
| Attached ADU | not reported | ||
| Garage conversion | not reported | ||
| Junior ADU (JADU) | not reported | ||
| Unclassified | too few to say | 7 |
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
From permit to completion
Of the 33 ADU permits Laguna Niguel reported issuing from 2020 through 2023, 19 (58%) have a completion reported to the state. For those, the median time from permit to completion was 11 months.
The state reports don't record expired or cancelled permits, and a completion the city hasn't reported looks the same as an unfinished project, so the share is a floor. Years with incomplete reports are left out.
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 Laguna Niguel? Feature your business on this page.
Questions about ADUs in Laguna Niguel
How many ADUs have been permitted in Laguna Niguel?
Public records show 62 ADU permits in Laguna Niguel through 2025, nearly all since 2019. 15 in 2025. 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.
Can I build an ADU on my property in Laguna Niguel?
California law allows ADUs on most lots with a house, including in Laguna Niguel, 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 Laguna Niguel?
Apply with the City of Laguna Niguel's Community Development Department, which offers free pre-approved ADU plans. 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.