ADU Pass
Boulevard
ADU Pass helps homeowners in Boulevard, 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
Allowed by-right ministerial under state law via County PDS. The dominant siting constraints in Boulevard are very-high fire-hazard severity (CBC Chapter 7A WUI construction), well/septic capacity on rural acreage, defensible-space mandates, and back-country access road standards. ADU water service typically draws on private well or County Service Area No. 137 (Live Oak Springs).
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 150 | $1,730 | $49,500 | $51,230 |
| 600 | 600 | $2,010 | $198,000 | $200,010 |
| midpoint | 675 | $2,080 | $222,750 | $224,830 |
| maximum | 1,200 | $3,770 | $396,000 | $399,770 |
Fee breakdown (as of 2026-04)
Permitting process
- (~2d)
- (~5d)
- (~1d)
- (~42d)
- (~14d)
- (~28d)
- (~3d)
Viability (permitted uses)
- Long-term rental: yes Long-term rental by-right; California owner-occupancy preemption since 2024.
- Short-term rental: with-restrictions County STRO ordinance does not apply to unincorporated areas as of 2026; Boulevard STR market is small but real (Tecate Divide / In-Ko-Pah backpacking, motorcycle-touring on the I-8 / SR-94 / Old Highway 80 corridor, occasional wind-farm contractor housing). Confirm parcel-level use with PDS.
- Office rental: with-restrictions External office tenant rental requires a Minor Use Permit / home-occupation review.
- Home office: yes Owner home-occupation permitted; County rules limit signage and customer traffic — practical given Boulevard's remote location and limited drive-by exposure.
- Studio / workshop: yes Personal artist / workshop use of ADU permitted as accessory residential use.
- Agriculture: with-restrictions Many Boulevard parcels are A70 / A72 agricultural-zoned; ADU is a permitted residential accessory but agricultural support buildings are a separate permit. Working ranches and small-vineyard / orchard operations are common.
- Relative support: yes Multigenerational / relative-occupancy ADU permitted. File Rev. & Tax. Code 74.3 Claim for New Construction Exclusion at permit issuance for parent/child intergenerational housing.
Incentives
- Unincorporated green-design fee discount (7.5% off PDS permit-related fees)
- ADU separate-sale condo conversion program (post-March 2026)
Pre-approved plans Pre-approved plans
Contacts
Staff: PDS Zoning Permit Counter (ADU pre-application zoning consult) PDSZoningPermitCounter@sdcounty.ca.gov, Boulevard Planning Group (formerly Sponsor Group) (Advisory body to County PDS for Boulevard CDP land-use referrals), San Diego County Department of Environmental Health & Quality (DEHQ) — Land & Water Quality Division (Septic / well / private-water-supply permits required on virtually all Boulevard parcels), CAL FIRE / San Diego County Fire — East County Battalion (Defensible space, WUI Chapter 7A, water-supply / cistern review for VHFHSZ parcels), County Service Area No. 137 — Live Oak Springs Water System (San Diego County DPW) (Water service for the small CSA 137 service area in Boulevard)
Utilities
- Water: County Service Area No. 137 — Live Oak Springs Water System (San Diego County DPW operated, ~2 mi of mains, single well, three 20K-gal tanks) for parcels in service area; private well for the rest of Boulevard · 21d connect · $4,800
CSA 137 covers a small portion of Boulevard (Live Oak Springs area); the majority of Boulevard parcels rely on private wells. Well permits go through DEHQ; depth and yield highly variable across the In-Ko-Pah / Tecate Divide geology. Back-country well failures during multi-year droughts are not uncommon; cistern with hauled-water backup is a recommended design pattern. - Sewer: On-site septic via San Diego County DEHQ permit (no public sewer in Boulevard) · 28d connect · $14,500
All Boulevard ADUs require an engineered or conventional septic system. Perc-test results often determine ADU feasibility on the rocky decomposed-granite soils of the Tecate Divide; some parcels require alternative-treatment (engineered) systems that materially increase cost. - Electric: San Diego Gas & Electric (SDG&E) — service drop from rebuilt Boulevard Substation (138 kV ECO Substation tie + Tule Wind interconnect) · 35d connect · $4,200
Boulevard sits at the convergence of the SDG&E ECO Substation 138 kV line and the Tule Wind / proposed Manzanita and Jordan wind interconnections. Service drops are reliable from the hardened Boulevard Substation but new-service trenching distances can be long on multi-acre parcels. PSPS (Public Safety Power Shutoff) exposure is significant — many Boulevard owners install PV + battery.
Property values & taxes
Construction timeline
Realistic total: best 9mo · typical 13mo · worst 20mo
Lead times in Boulevard reflect the very small local GC pool (most Boulevard owners use El Cajon-area or Pine Valley contractors who travel out), long material-delivery cycle (60-70 mi each way), and CBC Chapter 7A WUI envelope sequence that adds ~2 weeks vs non-fire-zone build. Winter snow / freeze occasionally interrupts work at 3,500 ft elevation Dec-Feb.
Modular pathway inspectors are occasional with modular
Financing
State ADU loans:
Insurance impact
HOA prevalence & preemption
Boulevard has near-zero HOA prevalence. Most parcels are large rural-residential or agricultural with no covenant administration. A handful of residential-cluster developments may have CC&Rs, but the back-country / ranching land pattern leaves the vast majority of parcels HOA-free. CA AB 670 / AB 3182 preempt HOA ADU prohibitions where they exist.
Regulatory overlays (4)
- wui-fire-zone
Boulevard sits in a heavily-mapped Very High Fire Hazard Severity Zone (CAL FIRE State Responsibility Area). Multiple recent wildfires have evacuated Boulevard parcels (August 2025 Roadrunner Lane / Moonlit Trail incident; numerous historical incidents). All ADU construction must comply with CBC Chapter 7A (ignition-resistant siding, Class A roofing, dual-pane windows, 1/8-inch vent screens, non-combustible eaves), 100-foot defensible space (PRC 4291), minimum driveway width / turnaround / fire-flow water supply (cistern + 2,500 gpm or NFPA 13D sprinkler tradeoff). - other
Adjacent / interspersed tribal reservations (La Posta Reservation immediately south; Manzanita and Campo reservations within 5-10 miles): tribal lands are outside County jurisdiction, but boundary parcels may have access, water, or utility-easement implications that require neighbor coordination not captured in the standard PDS process. - other
Wind-energy infrastructure overlay: McCain Valley Tule Wind Project (operating, 132 MW), proposed Manzanita Wind, proposed Jordan Wind, and rebuilt Boulevard Substation create a localized renewable-collection landscape. Parcels within 1-2 miles of operating turbines have documented residential complaints about noise / shadow-flicker / health concerns; SDG&E ECO Substation 138 kV line traverses portions of the area. - other
Cleveland National Forest boundary: portions of Boulevard adjoin Cleveland NF (Pine Valley / Mount Laguna ranger districts); USFS-adjacent parcels may have additional access, fuel-management, and emergency-response considerations.
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
- Amendment
Contractor market (aggregate)
Legal history (timeline)
Current ordinance: San Diego County Code Title 6 (Zoning Ordinance) — Accessory Dwelling Unit provisions, as amended by Ord. 10693 (2020), Ord. 10749 (2023), and the March 2026 separate-sale program; layered with Mountain Empire Subregional Plan, adopted 2020-08-26, last amended 2026-03-04
- 1979-09-19 — Mountain Empire Subregional Plan adopted (San Diego County General Plan) (city-ordinance)
The Mountain Empire Subregional Plan provides community-scale land-use, circulation, and conservation guidance for the Boulevard, Campo / Lake Morena, Jacumba, Potrero, and Tecate communities.
Effect: Established the rural-residential and rural-commercial designations that now govern ADU siting in Boulevard. The plan emphasizes fire-safe rural design and protection of the I-8 / SR-94 visual corridor. Updated through subsequent County General Plan amendments. - 2011-08-03 — San Diego County General Plan Update — Mountain Empire chapter refreshed (city-ordinance)
The 2011 County General Plan Update reaffirmed the Boulevard community designations within the Mountain Empire subregion, including very-low-density residential / agricultural zoning consistent with the constrained groundwater and high fire-hazard environment.
Effect: Set the modern density and lot-size framework against which ADU permits are evaluated. Most Boulevard parcels are 4-40 acre rural-residential or agricultural — generous envelopes for ADU siting but heavy fire / water / access overlays. - 2018-01-01 — Tule Wind Project commercial operation begins in McCain Valley north of Boulevard (other)
57-turbine, 132 MW utility-scale wind farm energized after 13 years of permitting. Project tied into rebuilt Boulevard Substation via the SDG&E ECO Substation 138 kV line.
Effect: Materially changed Boulevard's energy-infrastructure landscape: the Boulevard Substation is now a regional renewable-collection node. ADU service drops from this hardened substation, but the wind-development context drives separate land-use considerations (avigation, tribal proximity, viewshed) on parcels adjacent to McCain Valley. - 2020-08-26 — San Diego County Ord. No. 10693 — ADU ordinance conforming to AB 68 / AB 881 / SB 13 (county-ordinance)
Conformance update to 2019 statewide ADU reform package.
Effect: Established ministerial 60-day permit review, removed impact fees on ADUs under 750 sqft, codified state minimum sizes. Applies in Boulevard. - 2023-12-06 — San Diego County Ord. No. 10749 — ADU ordinance update for AB 2221 / SB 897 (county-ordinance)
Conformance update incorporating 2022 statewide ADU clarifications.
Effect: Tightened review-clock administration; clarified what County PDS can require during plan check. - 2026-03-04 — San Diego County adopts AB 1033 separate-sale ADU condo-conversion program (county-ordinance)
Board of Supervisors adopted ADU condo-conversion program for unincorporated communities. Effective April 4, 2026.
Effect: Boulevard ADUs may, on new permits, be condo-mapped for independent sale separate from the primary dwelling — meaningful for the area's modest land-value market where bundling/unbundling small structures matters.
Known issues (3)
- other — VHFHSZ insurance market: admitted-carrier residential homeowners insurance is increasingly difficult to obtain in Boulevard; many owners are on CA FAIR Plan + DIC wraps. Lender escrow on ADU construction loans can stall on insurance binder issues.
- other — Septic-feasibility risk: rocky decomposed-granite soils mean some Boulevard parcels cannot pass perc-test for conventional septic; alternative-treatment (engineered) systems add $15-25K to ADU budget when required.
- other — PDS field inspections from Kearny Mesa are 70 mi each way; expect inspection clustering and limited reschedule flexibility.
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
- 91905
Post Office
- 39550 Old Highway 80 Ste A, 91905