ADU Pass
Coronado
San Diego County portion
Also in: No County
ADU Pass helps homeowners in Coronado, San Diego County, California navigate the permit paperwork for building an accessory dwelling unit. This area covers 1 ZIP code.
Map
ADU details
ADU legality: allowed-with-restrictions
ADU is by-right ministerial under state preemption + CMC §86.56.105, but two physical overlays touch most Coronado parcels: (1) Coastal Zone (entire city is in California Coastal Commission jurisdiction with a certified Local Coastal Program), and (2) NAS North Island ALUCP review zones for ~35 homes plus several school sites along the southern shore. The overlays do not prohibit ADUs but add coastal-permit-exemption review and, in APZ/noise-contour parcels, sound-attenuation construction.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 150 | $2,200 | $105,000 | $107,200 |
| 600 | 600 | $2,200 | $420,000 | $422,200 |
| midpoint | 575 | $2,200 | $402,500 | $404,700 |
| maximum | 1,000 | $8,500 | $700,000 | $708,500 |
Fee breakdown (as of 2026-04)
Permitting process
Viability (permitted uses)
- Long-term rental: yes Long-term rental of an ADU is explicitly permitted by CMC §86.56.105 with no owner-occupancy requirement post-AB 976 (2024).
- Short-term rental: no Coronado prohibits short-term rentals (under 26 days) of any residential dwelling unit, including ADUs, in residential zones (CMC §86.46 — Short-Term Vacation Rentals). The ADU ordinance §86.56.105(F) requires a deed-restricted minimum 31-day rental term.
- Office rental: no ADUs are residential by definition under Government Code §65852.2; office rental to outside tenants would require rezoning or a conditional use permit and is not consistent with ADU status.
- Home office: yes Owner home occupation in an ADU is permitted under CMC §86.42 (home occupation) with limits on customer traffic, signage, and exterior changes.
- Studio / workshop: yes Personal artist studio / workshop use is consistent with residential occupancy; commercial sales would push it into home-occupation territory.
- Agriculture: no Coronado has no rural-residential or agricultural zones; the city is built-out residential / commercial / military / public.
- Relative support: yes Family occupancy of an ADU or JADU is explicitly permitted; JADUs require owner occupancy of one of the units (primary or JADU) per state law.
Incentives
Contacts
Utilities
- Water: California American Water — Coronado District (PWS ID CA3710001); supply purchased from City of San Diego via San Diego County Water Authority / MWD · 30d connect · $5,500
- Sewer: City of Coronado Public Services (city-operated wastewater collection; treatment via Point Loma WWTP) · 21d connect · $5,000
- Electric: San Diego Gas & Electric (SDG&E) · 30d connect · $2,500
- Gas: San Diego Gas & Electric (SDG&E) · 21d connect · $1,800
Property values & taxes
Construction timeline
Realistic total: best 9mo · typical 13mo · worst 20mo
Modular pathway inspectors are occasional with modular
Financing
State ADU loans:
Insurance impact
Coronado coastal exposure pushes premium delta above San Diego inland baselines; lenders and the National Flood Insurance Program may require flood insurance on SFHA parcels. AICUZ-affected parcels do not directly drive premium but underwriters note the airport adjacency.
HOA prevalence & preemption
California has the strongest statewide HOA-preemption regime in the US for ADUs, built from AB 670 (2019) and AB 3182 (2020) into Civil Code §§ 4740 / 4741 (Davis-Stirling). HOAs cannot ban ADUs or restrict rentals below 25% of separate interests. Coronado HOA prevalence concentrates in Coronado Cays (full HOA control), the Coronado Shores high-rises (Coronado Shores Association), and Coronado Cays subdivisions; the historic village core is mostly fee-simple with no HOA. The 2026 Carlsbad case (CalMatters) established that an HOA's documented design-standards regime can effectively delay ADU approval, which will likely extend to similar Coronado design-review-active HOAs.
Regulatory overlays (5)
- coastal-commission
Entire City of Coronado is within the California Coastal Commission jurisdiction with a certified Local Coastal Program (LCP). Most ADUs qualify for a Coastal Permit Exemption finding via Handout 711; a full Coastal Development Permit is required only for projects in the Appeal Zone or with discretionary review triggers. - historic-district
Coronado has a citywide Historic Resource Inventory and a Historic Resource Alteration Permit (HAP) requirement. December 2025 code amendments require historic-significance review for any structure 75+ years old (built before ~1951) not on Tier 3 of the Inventory before demolition or street-visible alterations. The Hotel del Coronado district and the Tent City Avenue / R Avenue cores carry the densest HAP exposure. - airport-noise-zone
Naval Air Station North Island AICUZ / Airport Land Use Compatibility Plan (2020) overlays Clear Zone, Accident Potential Zone I, APZ II, and 65/70/75 dB CNEL noise contours over portions of Coronado. ~35 homes plus several school facilities sit in non-conforming zones. APZ parcels face density and use restrictions; 65+ dB CNEL parcels require sound-attenuation construction (typically extra wall STC, attic insulation, and acoustical windows). - flood-zone
FEMA Flood Insurance Rate Map shows Special Flood Hazard Areas (SFHA — AE and VE zones) along the Glorietta Bay shore, Coronado Cays, and the Silver Strand. SFHA parcels require elevation certificates and flood-resistant construction; Coronado participates in the National Flood Insurance Program with a CRS rating that delivers a 5-15% premium discount. - seismic-retrofit-zone
Seismic Design Category D2 per ASCE 7 due to proximity to Rose Canyon Fault and Coronado Banks fault zone. Soft-story dwelling concerns apply to pre-1978 multi-unit conversions but rarely affect new detached ADU construction.
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
Legal history (timeline)
Current ordinance: Coronado Municipal Code §86.56.105 — Accessory dwelling units and junior accessory dwelling units, adopted 2020-02-04, last amended 2024-09-01
- 2020-02-04 — Coronado Ordinance No. 2020-03 — initial conformance with AB 68 / AB 881 / SB 13 / AB 670 (city-ordinance)
First Coronado ADU ordinance amending CMC §86.56.105 to bring the local code into conformance with the 2019-2020 California ADU statute package.
Effect: Replaced the prior conditional-use-permit process with a ministerial approval pathway, removed owner-occupancy requirement for ADUs, established 850/1000 sqft size caps, and codified by-right detached ADU + JADU per single-family lot. - 2021-02-16 — Coronado Ordinance No. 2021-02 — second conformance amendment (city-ordinance)
Cleanup amendment refining ADU and JADU standards in CMC §86.56.105 following 2020 HCD review.
Effect: Adjusted internal cross-references and clarified that JADUs do not require independent kitchen plumbing where state law permits a shared bathroom. - 2024-04-16 — Coronado Ordinance No. 2024-02 — SB 897 / AB 2221 / AB 976 / SB 9 conformance (city-ordinance)
Comprehensive update to CMC §86.56.105 (ADU/JADU) and §86.56.180 (SB 9 two-unit residential developments). Codified September 2024.
Effect: Permanently removed owner-occupancy enforcement (AB 976), standardized 16-ft height baseline with multi-story exceptions, clarified converted-structure setback exemption, and added an SB 9 two-unit residential pathway in single-family zones (with R-1A exemption for the historic core). - 2024-12-10 — HCD findings letter on Coronado ADU ordinance (state-law)
California Department of Housing and Community Development reviewed Ord. 2024-02 and issued a findings letter to the City of Coronado.
Effect: HCD review concluded the Coronado ADU ordinance package as adopted. Coronado must act on any non-compliance findings within 30 days of receipt or risk the ordinance being deemed null and void under Government Code §65852.2(h). - 2025-12-04 — Coronado Historic Resource Code amendments (city-ordinance)
Amendments to the Historic Resource Code requiring any structure 75 years or older not listed in Tier 3 of the Historic Resources Inventory Tier Matrix to undergo historic-significance review prior to demolition or alteration of street-visible original features.
Effect: Added a Historic Resource Alteration Permit (HAP) gate for ADU projects on parcels with 75+ year structures. Detached new-construction ADUs in rear yards typically clear without HAP; conversions of garages or accessory structures on contributing parcels do not.
Known issues (2)
- policy-review — December 2025 Historic Resource Code amendments newly trigger Historic Resource Alteration Permit (HAP) review for any structure 75+ years old not in Tier 3 of the Historic Resources Inventory. ADUs that involve alteration of street-visible original features on contributing parcels may incur 60-90 days of additional review and Historic Resource Commission hearing.
- other — Single bridge access (SR-75 Coronado Bridge) constrains contractor mobilization and material delivery; combined with Naval Base Coronado security perimeter, this lengthens construction schedules versus mainland San Diego County peers and inflates GC mobilization costs by ~10-15%.
San Diego County — county ADU rules and overlays
County ADU ordinance
San Diego County regulates ADUs on parcels in the unincorporated county under Title 6 of the County Code (Zoning Ordinance), Sections 6156.x. The county's ADU framework layers on top of California Government Code sections 65852.2 (ADU) and 65852.22 (JADU), which preempt many local standards statewide; the county ordinance fills in the locally-controlled parameters (setbacks, design standards, parking in non-transit unincorporated areas, fire-safe design in VHFHSZ) that state law leaves to local choice. The current ordinance reflects amendments adopted 2020 (Ord. No. 10693) and 2023 (Ord. No. 10749) to conform with AB 68 / AB 881 (2019), AB 976 (2019 owner-occupancy elimination through 2024), SB 13 (2019 fee reductions), AB 2221 / SB 897 (2022 design/permit clarifications), and AB 1033 (2023 condo-ADU optional program; San Diego County has not opted into AB 1033 condo separation as of 2026-04-20). The county permits up to one ADU plus one JADU per single-family parcel by right, and the state-mandated two ADUs per multifamily lot; parking is not required on ADUs within 1/2 mile of transit. The county's distinct contributions on top of state law are the fire-hardening / defensible-space design standards for ADUs sited in Very High Fire Hazard Severity Zones, the airport-noise compatibility review for ADUs within Airport Land Use Compatibility Plan (ALUCP) zones, and the Coastal Development Permit (CDP) requirement for ADUs in the county's certified Local Coastal Program (LCP) jurisdiction.
- San Diego County Code of Regulatory Ordinances Title 6 (Zoning) — Accessory Dwelling Unit provisions
- PDS ADU Technical Bulletin and applicant handouts
- Ordinance No. 10693 — 2020 ADU ordinance conforming to AB 68 / AB 881 / SB 13
- Ordinance No. 10749 (approximate) — 2023 ADU ordinance update for AB 2221 / SB 897 / AB 1033
State-floor overlay: California state law (Gov. Code 65852.2, 65852.22) preempts most local ADU regulation. The state sets ministerial-approval requirements, caps fees, mandates 60-day permit review, forbids local owner-occupancy requirements through 2024 (extended effectively through AB 976 / subsequent amendments), sets minimum allowed sizes (850 sqft one-bedroom, 1000 sqft two-bedroom), forbids parking requirements within 1/2 mile of transit or on replacement-covered-parking ADUs, and caps impact fees at zero for ADUs under 750 sqft. San Diego County's ordinance reiterates and applies these floors, adding only the locally-controlled fire, airport, and coastal overlays. Where a project is in a VHFHSZ or coastal-commission jurisdiction, state ADU preemption still applies to the ADU allowance itself but does not preempt the county's separate fire and coastal authority over site-design standards.
County regulatory overlays
San Diego County administers or co-administers several overlay regimes that materially affect ADU siting on unincorporated parcels: (1) the California Coastal Commission's jurisdiction along the coastal zone (a narrow band up to 5 miles inland in some places), implemented through the county's certified Local Coastal Program (LCP) covering unincorporated coastal segments; (2) Very High Fire Hazard Severity Zones (VHFHSZ) designated by CAL FIRE and reviewed by the State Board of Forestry, which cover very large portions of the unincorporated back-country and drive defensible-space, ignition-resistant-construction, and access requirements; (3) FEMA Special Flood Hazard Areas (SFHA) along the San Diego River, San Dieguito River, San Luis Rey River, Otay River, Sweetwater River, Tijuana River, and associated coastal zones; and (4) Airport Land Use Compatibility Plans (ALUCP) administered by the San Diego County Regional Airport Authority's Airport Land Use Commission around MCAS Miramar (federal military), NAS North Island / Naval Outlying Landing Field Imperial Beach (federal military), Gillespie Field (Santee, county-owned), McClellan-Palomar (Carlsbad, county-owned), Brown Field (Otay Mesa, City of San Diego), Montgomery-Gibbs Executive (Kearny Mesa, City of San Diego), Ramona Airport (county-owned), Fallbrook Community Airpark (county-owned), Oceanside Municipal, and Jacumba Airport. Seismic-retrofit overlays are not a county-administered regime in San Diego (unlike parts of Los Angeles / San Francisco); California seismic building-code compliance applies statewide through the California Building Code adopted by the county.
- California Coastal Commission / County Local Coastal Program (LCP) — The county's LCP covers the unincorporated coastal segments near Del Mar Mesa, Torrey Pines extensions, Crest / Harmony Grove (tributary areas), and the Camp Pendleton / Oceanside boundary. An ADU within the coastal zone requires a Coastal Development Permit (CDP) unless categorically excluded; most single detached ADUs qualify for an Administrative CDP (noticed but ministerial-like) while those in sensitive-biological or visually-sensitive settings may require a heard CDP. The Coastal Commission retains appeal jurisdiction over county CDPs within the defined appeals area. State law (Gov. Code 65852.2(j)) preserves the CDP requirement for ADUs in the coastal zone notwithstanding the otherwise-ministerial state ADU framework.
- CAL FIRE / State Board of Forestry Very High Fire Hazard Severity Zones (VHFHSZ) and County Fire Code — Very large portions of unincorporated San Diego County — most of the East County back-country including Julian, Warner Springs, Descanso, Pine Valley, Jacumba, Campo, Boulevard, Dulzura, Potrero, Palomar Mountain, Cuyamaca, and the San Diego / Cleveland National Forest interface — are designated VHFHSZ in either the State Responsibility Area (SRA) or the county's Local Responsibility Area (LRA). An ADU in a VHFHSZ must comply with California Building Code Chapter 7A (WUI-rated exterior materials: ignition-resistant siding, dual-pane windows, 1/8-inch-max vent screens, Class A roofing, non-combustible eaves / soffits / decks), minimum 100-foot defensible-space per Pub. Res. Code 4291, minimum driveway width and turnaround per fire-district standards, and minimum fire-flow water supply (2,500 gpm residential standard, reduced for sprinklered ADUs per Sec. R313). CAL FIRE or the local FPD (Alpine, Bonita-Sunnyside, Deer Springs, Julian-Cuyamaca, Lakeside, North County, Pine Valley, Rancho Santa Fe, Rural FPD of San Diego County, Valley Center, etc.) reviews the ADU permit. The 2025 wildfire season reinforced these requirements; no county-wide moratorium has been imposed, but permit backlogs lengthen post-fire when affected areas surge rebuild applications.
- FEMA Special Flood Hazard Areas (SFHA) — National Flood Insurance Program — The county administers FEMA NFIP floodplain regulations for unincorporated parcels. Principal SFHA extents are along the San Luis Rey River (Bonsall, Pala, Pauma), San Dieguito River (Lakeside, Ramona uplands), San Diego River (Lakeside, Santee extensions), Sweetwater River (Spring Valley extensions), Otay River (Jamul, Dulzura, Otay Mesa extensions), and Tijuana River estuary (Tijuana / Imperial Beach extensions). ADUs in an SFHA require lowest-floor elevation to or above Base Flood Elevation plus 1 ft county freeboard, flood vents on enclosures below BFE, anchoring, and a post-construction Elevation Certificate. 2024-2025 saw several FEMA FIRM revision studies for Otay, San Luis Rey, and Sweetwater watersheds; owners should confirm current effective panel before design.
- Airport Land Use Compatibility Plans (ALUCP) — San Diego Regional Airport Authority ALUC — The San Diego County Regional Airport Authority serves as the ALUC for all airports in the county. ALUCP airport influence areas (AIAs) extend roughly 2-5 miles beyond each airport depending on runway configuration and establish safety zones (Zones 1-6) and noise contours (60/65/70 dB CNEL). Principal ALUCP overlays affecting unincorporated parcels are MCAS Miramar (extensive AIA covering Scripps Ranch fringes, Miramar Ranch North, Tierrasanta approaches, into unincorporated Rancho Santa Fe / Poway fringes), Gillespie Field (AIA extending into unincorporated Lakeside, El Cajon fringes, Bostonia), McClellan-Palomar (Carlsbad-adjacent unincorporated areas), Ramona Airport (large rural AIA), and Fallbrook Community Airpark (Bonsall / Fallbrook). An ADU in a safety zone may face density restrictions, CC&R / avigation-easement recording requirements, and noise-attenuation construction standards (STC-rated windows, forced-air HVAC with acoustic treatment). The ALUC reviews county-referred projects; in a safety-zone conflict the county may override only by a super-majority Board vote per PUC 21676.
- San Diego County Biological Mitigation Ordinance / Multiple Species Conservation Program (MSCP) — The county's MSCP covers south county unincorporated areas and establishes Pre-Approved Mitigation Areas and a Biological Mitigation Ordinance that triggers biological review for grading and construction in designated preserve-land overlays. An ADU outside the existing dwelling footprint that requires grading in a designated MSCP preserve or Biological Resource Core / Linkage area will trigger a biological review / mitigation obligation on top of the ministerial ADU permit. Inside a parcel's previously-disturbed building envelope the MSCP typically does not add requirements. The East County MSCP Subarea Plan remains pending final approval as of 2026-04-20.
County permitting (unincorporated parcels)
The County of San Diego Planning & Development Services (PDS) department is the single-point-of-contact for ADU permits on parcels in the unincorporated county. Unincorporated San Diego County covers approximately 3,570 square miles (about 79% of the county's 4,526 sqmi land area) and includes densely developed fringe areas (Ramona, Alpine, Lakeside, Spring Valley, Fallbrook, Valley Center), rural back-country (Julian, Warner Springs, Jacumba, Boulevard, Campo), and tribal lands (which are not county-permitted). The 18 incorporated cities (San Diego, Chula Vista, Oceanside, Escondido, Carlsbad, Vista, San Marcos, El Cajon, Santee, La Mesa, Encinitas, National City, Poway, Coronado, Imperial Beach, Lemon Grove, Del Mar, Solana Beach) permit their own ADUs independently. PDS combines planning / zoning review, building plan review, grading / drainage review, fire-district referral (most unincorporated areas are served by CAL FIRE / County Fire Authority or a local Fire Protection District rather than a city fire department), and environmental review (CEQA applicability is normally exempt for ministerial ADUs per Gov. Code 65852.2(f) and Pub. Res. Code 21080(b)(8)).
California state — ADU law and programs
State ADU law
California has the most aggressive statewide ADU preemption regime in the US, built from ~15 bills passed 2019-2025 and enforced by the Department of Housing and Community Development (HCD). The 2026 HCD ADU Handbook addendum (in effect with the 2025 Title 24 code cycle) is the operative state-level reference. The regime does four things at once: (1) preempts local zoning that would ban or unreasonably restrict ADUs; (2) imposes by-right ministerial approval with short statutory deadlines; (3) caps fees and utility-connection charges; and (4) empowers HCD to void non-compliant local ordinances.
State HOA preemption
California has the strongest statewide HOA-preemption regime in the US for accessory dwelling units, built from two bills: AB 670 (2019) voided ADU-prohibiting covenants on single-family residential lots, and AB 3182 (2020) extended and codified the preemption into the Davis-Stirling Common Interest Development Act (Civil Code §§ 4740 / 4741). The combination prohibits common-interest communities from banning ADUs, restricting rentals below 25% of separate interests, or treating ADUs as separate HOA interests. Limits remain: HOAs retain authority over reasonable design standards and statutory height limits, and the 2026 Carlsbad case (CalMatters coverage) established that an HOA's documented design-standards regime can effectively delay or constrain ADU approval short of outright prohibition.
State financing programs
California's flagship state-level ADU financing program — the CalHFA ADU Grant Program — is paused and has not been refunded since the original $100 million allocation was fully deployed 2023-12-28. The program provided up to $40,000 per qualifying homeowner for pre-construction and non-recurring closing costs and financed approximately 2,500 ADUs in two rounds. As of 2026-04, no new funding round has been announced in the state budget. CalHFA continues to publish anti-scam warnings because bad actors actively solicit homeowners claiming access to grant funds that no longer exist. State-level financing activity has shifted to local pilot programs (San Francisco, San Jose, Los Angeles, San Diego) and private financing products (Fannie Mae ADU mortgage, HELOC, construction-to-permanent).
State housing programs
California's state-level ADU programs are concentrated at HCD (technical guidance, ordinance review, enforcement) and the paused CalHFA grant pipeline (covered under stateFinancing). The state does not operate a central pre-approved ADU plan library — instead, AB 1332 (2024) created a preemption framework for local pre-approved plans with a 30-day ministerial-approval deadline, and major cities (Los Angeles, San Diego, San Jose, Sacramento, Berkeley) have rolled out their own plan catalogs. The California YIMBY coalition and other housing-policy organizations play an influential role in bill drafting; they are not state agencies but effectively drive much of the ADU legislative agenda. The Title 24 code cycle (now 2025, in effect for 2026 permits) is the authoritative building-code baseline.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Code
- 92118
Post Office
- 1320 Ynez Pl, 92118