Bolthole Index

San Diego County, California

Building permits, zoning and land rules in San Diego County, California

41Index Score / 100
#34 of 58 in California

Unincorporated San Diego County, California requires building permits for residential and commercial structures, although limited exemptions depend on a structure's size and location1. Planning & Development Services administers county zoning outside incorporated cities2. Septic approval comes from the Department of Environmental Health and Quality before a building permit can be issued3.

At a glance

Building permit
Required for residential and commercial structures, with limited exemptions1
Zoning
County zoning applies in unincorporated areas; cities use their own rules2
Septic permits
Handled by the San Diego County Department of Environmental Health and Quality3
RV living
Ordinary RVs and Park Model Trailers are not approved for permanent habitation4
Tiny homes on wheels
Permanent habitation is possible for a qualifying, permitted THOW5
Owner-builder
Allowed with conditions, but permits and inspections still apply6
Setbacks
Parcel-specific under the applicable setback designator and schedule7
Wells
A county permit is required to install or modify a well8

Who to call

Building permits

San Diego County PDS Building Services Division

Building permits, plan review and inspections for unincorporated San Diego County

(858) 694-3900

Online permits →

Planning & zoning

San Diego County Planning & Development Services

Zoning administration and land-use questions for unincorporated San Diego County

(858) 694-3900

Septic permits

DEHQ Land and Water Quality Division, Onsite Wastewater Systems

Onsite wastewater system permits, design review and inspections

(858) 565-5173

[email protected]

5500 Overland Avenue, Suite 110, San Diego, CA

Contact details are copied from each office’s official page and were checked against it on September 29, 2026.

Do you need a building permit in San Diego County, California?

Yes, for most residential and commercial construction in unincorporated San Diego County. The Building Services Division issues the permits, while only structures meeting specific size and location requirements qualify for exemptions1. Even an exempt project must comply with zoning, health and safety codes, and other applicable government rules1. Permitted work is inspected as construction proceeds, and a county inspector must approve each successive part9. The completed, signed permit card serves as the Certificate of Occupancy, so retain it after final approval10. California's owner-builder exemption can excuse an eligible owner from contractor licensing, but it does not eliminate San Diego County building permits or inspections6.

Who is the San Diego County building department, and how do you reach it?

San Diego County Planning & Development Services' Building Services Division handles building permits, plan review and inspections for unincorporated property11. Applicants can use the county's online services to apply for simple building permits, check permit status, schedule inspections and pay fees11. The county assigns each project a Permit Record ID, and every listed condition must be satisfied before permit issuance; those conditions can include fire-district approval, flood control, septic review and driveway review12. Building fees vary by project rather than following one universal price, so use the linked fee information and project handouts to identify applicable charges13. Call the county information line shown above when the project is not eligible for a simple online permit or when an exemption is uncertain11.

Does San Diego County have zoning?

Yes. Published county zoning districts govern land and buildings in unincorporated San Diego County, while incorporated cities administer their own zoning14. For an unincorporated parcel, use the county's zoning tools or GIS to identify the exact zone and property-specific regulations before designing a house2. Setbacks depend on the parcel's setback designator and schedule, and special street, General Plan circulation and more restrictive fire-code setbacks can also apply7. Building height likewise depends on the parcel's height designator; the schedule varies by allowable feet and stories, and a Major Use Permit is required above 60 feet15. An ADU or JADU requires a building permit and an existing or planned main house on residential property in unincorporated San Diego County16. We could not confirm a countywide minimum dwelling size, so ask Planning & Development Services about the parcel's zone and proposed dwelling type17.

How do septic permits work in San Diego County?

The San Diego County Department of Environmental Health and Quality permits onsite wastewater systems under the county ordinance and approved local management program, and DEHQ approval is required before Planning & Development Services can issue a building permit3. DEHQ reviews new designs, repairs and modifications and performs installation inspections18. Only 12.3% of county soils lack severe limitations for a conventional drain field, so arrange the site evaluation before fixing a house location or purchase budget19. A parcel with difficult soils may require supplemental treatment or a redesigned layout, but the site review determines that outcome3. Contact the DEHQ duty desk at the office information above for the applicable application and review sequence18.

Can you live in an RV or tiny home on your land in San Diego County?

Ordinary recreational vehicles and Park Model Trailers are not approved for permanent habitation on private lots in unincorporated San Diego County4. Temporary Park Model placement requires Planning & Development Services approval and must qualify as temporary occupancy, temporary health care or farm employee housing4. San Diego County provides a distinct permanent route for a Tiny Home on Wheels: a qualifying THOW may receive a habitation permit on a lot that allows a single-family dwelling5. The THOW must meet the county's construction, fire-safety, utility, wastewater, siting, registration and zoning conditions; it may be no larger than 430 square feet or higher than 16 feet5. A qualifying THOW can also serve as an ADU, subject to the applicable ADU and parcel rules516.

Building a home in San Diego County: the steps, in order

  1. Confirm that the parcel is unincorporated, then identify its zone, setback designator, height designator and overlays with Planning & Development Services14715.
  1. Confirm that the proposed dwelling type is allowed; an ADU needs an existing or planned main house, and a THOW must qualify under the county's permanent-habitation standards165.
  1. Arrange DEHQ septic review before permit issuance, and obtain a separate county permit if installing or modifying a well38.
  1. Submit plans to Building Services and clear every condition attached to the Permit Record ID12.
  1. If acting as owner-builder, verify that the licensing exemption fits the work; permits and inspections still apply6.
  1. Request inspections during construction, pass the final inspection and retain the completed permit card as the Certificate of Occupancy910.

What should you check before buying land in San Diego County?

Verify legal access and determine whether driveway work enters a public right-of-way or county easement, because improvement plans or driveway review may apply20. If access connects to a state highway, a Caltrans encroachment permit is required21. Check septic feasibility early because only 12.3% of county soils lack severe limitations for a conventional drain field19. A new or modified well requires a San Diego County permit, and the county regulates well design, construction, modification and destruction8. If a seller suggests the land can be split, verify the subdivision path and required access, drainage, erosion-control, water and fire improvements before valuing extra lots22. Finally, verify parcel-specific zoning and setbacks instead of relying on a listing description147.

Watch-outs

  • Ordinary RVs and Park Model Trailers are not approved for permanent habitation, but a qualifying THOW has a separate county permit route for permanent habitation45.
  • DEHQ septic approval must come before building-permit issuance, and only 12.3% of county soils lack severe limits for a conventional drain field319.
  • San Diego County setbacks and building heights are parcel-specific, and fire-code or street-related setbacks may be more restrictive715.
  • An owner-builder exemption concerns contractor licensing; the owner-builder must still obtain permits and pass inspections6.

Sources

  1. Building Division Home, quoted and re-checked
  2. Zoning Ordinance, quoted and re-checked
  3. San Diego County Code § 68.301, Purpose and Scope (2026 county census)
  4. Requirements for Placing a Certified Manufactured Home on a Private Lot, quoted and re-checked
  5. Tiny Home on Wheels Director’s Determination, quoted and re-checked
  6. Owner-Builder Overview, quoted and re-checked
  7. Zoning Ordinance Summary, quoted and re-checked
  8. Water Well Program, quoted and re-checked
  9. How to Obtain a Building Permit Summary, quoted and re-checked
  10. How to Obtain a Building Permit Summary, quoted and re-checked
  11. San Diego County PDS Building Services Division (sandiegocounty.gov)
  12. Building Division Home, quoted and re-checked
  13. Building Forms and Handouts, quoted and re-checked
  14. Zoning Ordinance, quoted and re-checked
  15. Zoning Ordinance Summary, quoted and re-checked
  16. Accessory Dwelling Units, quoted and re-checked
  17. San Diego County Planning & Development Services (sandiegocounty.gov)
  18. DEHQ Land and Water Quality Division, Onsite Wastewater Systems (sandiegocounty.gov)
  19. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  20. Improvement Plan Application User Guide, quoted and re-checked
  21. Encroachment Permits | Caltrans (California statewide rule), quoted and re-checked
  22. San Diego County Code of Regulatory Ordinances — Subdivision Ordinance, quoted and re-checked

Written September 29, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

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San Diego County in California

41
County map
San Diego County highlighted among the California counties · colored by Index score

How San Diego County scores

Seclusion22100% ev.
Self-Sufficiency4198% ev.
Admin Boringness54100% ev.
Durability41100% ev.
Property Autonomy56100% ev.
Carry Cost26100% ev.

Evidence strength: 99%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$941kTypical home
0.7%Property tax
$36,053Land / acre
13"Annual rain
27.9% of yrsSevere drought
24.6 / yr (+11.4)Mid-century 100°F days
78.2 daysMid-century dry spell
1.51" (+8.2%)Mid-century 1-day rain
1.11×Wildfire change factor
100%Forward climate coverage
$1,883Home insurance / yr
6.1% / yrInsurance growth
1.38%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
5,134,508People within 2 hr
569,378Radius comparison (15 mi)
776.7People / sq mi
24.8%Federal land
63.9%Land at 15% slope or less
12.3%Septic soil without severe limits
281,407 acWorkable land screen
38.7%Wooded land
19.6 tonsBiomass / forest ac
63.3°FAvg temp

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Answers from the rulebook for San Diego County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

San Diego County rules

  • Building permitRequired

    Construction, enlargement, alteration, conversion, repair, movement, or demolition of structures in unincorporated San Diego County.

    • Permits must be obtained prior to construction.
    • Work exempt from permits is addressed in Permit Requirement Exceptions form BD 110.
    • Even when a building permit is not required, projects must follow the Zoning Ordinance, Public Health and Safety Codes, and other County, state, or federal regulations.
    • The County states that certain structures meeting specific requirements, including size and location, may be exempt from building permits.
    “A permit is required to construct, enlarge, alter, convert (including change of occupancy, use, or character), repair, move, or demolish a structure. Permits are also required for grading, plumbing, electrical, and mechanical work. Permits must be obtained prior to construction. For a list of work exempt from permit, see Permit Requirement Exceptions (form BD 110).”
  • InspectionsRequired

    Construction performed under a San Diego County building permit in the unincorporated county area.

    • In most areas of the County, at least one working day of notice is required for inspections.
    • The County may not be able to provide next-day inspections in some remote areas.
    • A building inspector must approve each part of subsequent construction.
    • An inspection must be requested and construction progress demonstrated every six months for a building permit to remain active.
    • Permits have a maximum duration of three years; expired permits may be renewed for a percentage of current fees and may be subject to new regulations in effect at renewal.
    • Changes to approved plans must be submitted, reviewed, and approved before work proceeds; inspections are delayed until the plan-change process is complete.

    inspection notice in most areas: >= 1 working day (Some remote areas may not provide next-day inspections.) · required inspection/progress interval to keep permit active: per 6 months · maximum permit duration: 3 years (Expired permits may be renewed for a percentage of current fees.)

    “A County building inspector must approve each part of the subsequent construction. Once construction begins, an inspection must be requested – and construction progress demonstrated – every six months for a building permit to remain active. Permits have a maximum duration of three years.”
  • Certificate of occupancyRequired

    Buildings covered by the San Diego County building-permit process in unincorporated San Diego County.

    • All required inspections, including final inspection, must be passed to obtain a Certificate of Occupancy.
    • The County does not provide a separate document signifying the Certificate of Occupancy.
    • The completed, signed-off permit card is the Certificate of Occupancy and should be retained.
    “All required inspections (including final inspection) must be passed to obtain a Certificate of Occupancy. (See Final Residential Inspection Requirements, form PDS 117) A separate document will not be provided to signify Certificate of Occupancy. The completed, signed-off permit card is the Certificate of Occupancy and should be retained.”
  • County-wide zoningPresent (with conditions)

    Land-use regulation in unincorporated areas of San Diego County.

    • The County Zoning Ordinance applies to areas of San Diego County that are not part of a city.
    • Incorporated municipalities administer their own zoning rules.
    “The Zoning Ordinance sets rules for how land can be used in areas of San Diego County that are not part of a city.”
  • Local zoningVaries (with conditions)

    Countywide aggregate of zoning authority: the County regulates unincorporated areas, while incorporated municipalities within San Diego County regulate land within their municipal boundaries.

    • The County Zoning Ordinance applies only in areas that are not part of a city.
    • The City of San Diego states that all properties within the city have zoning designations under its Land Development Code.
    • Other incorporated municipalities may have their own zoning ordinances and zoning maps.
    “All properties within the City of San Diego have zoning designations reflecting the current designations in the Land Development Code.”
    One more reviewed finding on this topic
    • Varies (with conditions) — Aggregate local zoning across San Diego County, including County zoning for unincorporated areas and separate municipal zoning within incorporated cities.
      “The Zoning Ordinance sets rules for how land can be used in areas of San Diego County that are not part of a city.”
  • Zoning districtsPublished (with conditions)

    County zoning districts and associated zoning regulations in the unincorporated areas of San Diego County.

    • The County Zoning Ordinance applies to unincorporated areas and requires land and buildings to conform to regulations applicable to the zone in which the land is located.
    • The ordinance does not apply to County parks, County facilities, Indian Reservation lands, federally owned or state-owned public lands, and certain specified County solid-waste projects.
    • Incorporated cities administer their own zoning rules.
    “All zones (Residential, Agricultural, Commercial,Industral, etc)”
  • SetbacksDistrict specific (with conditions)

    Setbacks for development in unincorporated San Diego County, determined by the parcel's setback designator and applicable setback schedule.

    • The setback letter refers to the Setback Schedule.
    • Special street setbacks may apply under Section 4816.
    • Additional setbacks may apply on streets in the County General Plan Circulation Element.
    • Fire Code setbacks may be more restrictive and must be checked with the local Fire Marshal.
    • For designator V, setbacks are established during planned development, use permit, or site plan review.
    • Setback schedule footnotes include exceptions for lot size, street width, adjoining uses, alleys, open space, and subdivision recording dates.

    setback designator: A through W (designator V is established during planned development, use permit, or site plan review) · front, side, and rear setbacks: schedule values feet (subject to schedule footnotes and potentially more restrictive Fire Code setbacks)

    “setback designator on the Setback Schedule”
  • Building heightDistrict specific (with conditions)

    Building height in unincorporated San Diego County, determined by the parcel's height designator.

    • The height schedule provides designator-specific maximum feet and story limits.
    • Any number of stories is permitted for applicable designators when all building-code and floor-area-ratio limitations are met.
    • Height in excess of 60 feet requires a Major Use Permit.
    • The applicable height designator is parcel-specific.

    maximum height: 15 to 60 feet (designator R allows greater than 60 feet; any height over 60 feet requires a Major Use Permit) · maximum stories: 1 to 4 or code/FAR limited stories (varies by height designator)

    “Height: Letter indicates height designator”
  • Living in an RVLimited

    Use or occupancy of trailer coaches, including recreational vehicles treated as trailer coaches, in unincorporated San Diego County.

    • Use or occupancy must be authorized by the County Zoning Ordinance.
    • A valid, unexpired trailer coach installation permit issued and approved by the Director of Planning and Land Use is generally required.
    • No installation permit is required for temporary trailer use during a trailer roundup when a Department of Environmental Health permit has been issued.
    • The application must include required supplementary information and the nonrefundable application fee specified in County Code Section 56.202.3.
    • The permit may include discretionary conditions, expires on its specified date, and may be revoked or suspended for noncompliance.

    permit validity: valid and unexpired · application fee: specified in Section 56.202.3 (nonrefundable)

    “except when authorized by The Zoning Ordinance of San Diego County and in accordance with a valid unexpired trailer coach installation permit”
    3 more reviewed findings on this topic
    • Prohibited — Permanent habitation of a Park Model Trailer or recreational vehicle on a private lot in unincorporated San Diego County.
      “Park Model trailers are not allowed for permanent use on private lots. [...] RV’s are not approved for permanent habitation.”
    • Temporary only (with conditions) — Temporary occupancy of a Park Model Trailer on a private lot in unincorporated San Diego County during construction of a single-family residence.
      “a Park Model trailer may only be used (with issuance of a Building Permit) [...] during construction of a single-family residence.”
    • Temporary only (with conditions) — Park Model Trailers, identified by the County as a type of recreational vehicle, on private lots in unincorporated San Diego County.
      “A Park Model Trailer shall not be used for permanent habitation”
  • Tiny homesLimited

    Permanent habitation of a Tiny Home on Wheels in unincorporated San Diego County.

    • The THOW must be designed and constructed to ANSI A119.5 standard for Park Models and have a certification sticker before permit issuance from an accredited third-party inspection agency.
    • Exterior walls must meet the stated noncombustible, ignition-resistant, heavy-timber, or log-wall requirements; stucco or cement plaster must be at least 7/8 inch thick, and applicable WUI guidelines apply.
    • Windows, eaves, soffits, fascia, roofing, fire sprinklers, loft egress, carbon-monoxide detectors, and smoke detectors must meet the determination's requirements; the fire-sprinkler requirement has an exception when the unit is used as an ADU and applicable ADU exemptions apply.
    • The THOW must not exceed 430 square feet measured from the inside face of walls and must have at least R-13 insulation in all exterior walls.
    • The THOW must remain licensed and registered with the California Department of Motor Vehicles, cannot move under its own power, and cannot have slide or pop-out features that increase habitable square footage.
    • The THOW must be at least six feet from other structures and parked on a paved pad meeting the specified asphalt or cement thickness requirements, with movement-prevention installations.
    • Required building permits must be issued for connection to electric, water, and sewer utilities; mechanical equipment must be incorporated into the structure rather than placed on the roof.
    • The THOW must be no greater than one story and no higher than 16 feet; a sleeping loft up to 150 square feet is allowed and is not considered a second story.
    • A THOW used as a single-family dwelling must comply with applicable main-building setbacks, building type, density, and other zoning regulations. The policy does not change property zoning or allowed density.
    • A THOW used as an ADU requires no additional parking, and displaced parking caused by its placement need not be replaced; however, it cannot block or remove required parking for the primary residence.
    • A qualifying THOW is eligible for a permit allowing permanent habitation and may be used on a lot that allows a single-family dwelling. Removal requires a demolition permit to remove the dwelling from county records.
    • For OWTS-served property, DEHQ review and approval of an OWTS Layout Report is required; secondary-dwelling OWTS density is generally limited to a combined six bedrooms with a conventional OWTS or ten bedrooms with supplemental treatment, subject to applicable acreage allowances.
    • All dwellings, including THOWs, must have an approved potable water source and wastewater-disposal method. Hauled water, composting toilets, holding tanks, and portable toilets are not approved for new THOW construction.

    maximum floor area: <= 430 square feet (measured from inside face of walls) · maximum height: <= 16 feet (maximum height) · maximum stories: 1 story (sleeping loft up to 150 square feet is not a second story) · minimum separation from other structures: >= 6 feet · minimum exterior-wall insulation: R-13 · maximum sleeping loft: <= 150 square feet (loft is not considered a second story)

    “A THOW meeting the above standards is eligible for a permit that would allow permanent habitation.”
  • Manufactured homesAllowed (with conditions)

    Permanent residential occupancy of eligible certified manufactured homes on private lots in unincorporated San Diego County.

    • A building permit may be obtained only if the home complies with Section 6506 of the County Zoning Ordinance.
    • Eligible mobile homes must have been constructed between September 15, 1971 and June 14, 1976.
    • Eligible manufactured homes must have been constructed on or after June 15, 1976 and have a California HCD insignia of approval or certification under the National Mobilehome Construction and Safety Standards Act of 1974.
    • The home must not have been altered in violation of applicable codes.
    • It must be occupied only as a residential use and conform to the County Zoning Ordinance, Subdivision Ordinance, and applicable Health and Safety Code provisions.
    • Installation on a designated foundation requires a PDS building permit and compliance with Health and Safety Code Section 18551(a).
    • Final occupancy approval requires the Director of Planning & Development Services to determine compliance with all applicable requirements and conditions.
    • Wildland-Urban Interface construction, roofing, ventilation, foundation, roof-pitch, and overhang requirements apply, including stated exceptions and Director waiver provisions.

    eligible mobile-home construction period: 1971-09-15 to 1976-06-14 · eligible manufactured-home construction date: >= 1976-06-15 or later (HCD insignia or federal certification required) · minimum roof pitch: >= 2:12 (Director waiver may apply under listed conditions)

    “may be permanently located on a private lot only upon compliance with the requirements”
  • Accessory dwellingsLimited

    Accessory dwelling units and junior accessory dwelling units on residential property in unincorporated San Diego County.

    • The property must be in unincorporated San Diego County, be considered residential, and already have an existing or planned main house or single-family dwelling.
    • An ADU must be attached or detached, provide independent living facilities, and be on the same lot as the main house. A JADU must be completely contained within an existing or proposed house; a JADU with direct interior access may share bathrooms with the main house.
    • All ADUs and JADUs must follow County regulations and require a building permit addressing zoning, building, health, and safety codes.
    • An ADU or JADU can be located on a residentially zoned property with an existing single-family residence; property-specific zoning must be checked through the County property summary report.
    • An attached ADU may be up to 50 percent of the single-family dwelling area, subject to a 1,200-square-foot maximum, with stated exceptions to the 50-percent limit when the main house has more than one bedroom.
    • A detached ADU may not exceed 1,200 square feet, regardless of the size of the single-family dwelling.
    • A JADU may not exceed 500 square feet.
    • The County's ADU impact-fee waiver program went into effect January 9, 2019 and ended January 9, 2024. Qualifying projects started before January 9, 2024 did not pay the plan-check fee, but projects whose permits were not issued by January 9, 2024 must pay fees typically collected at permit issuance.
    • The County adopted an AB 1033 program on March 4, 2026 allowing separate ADU sales in unincorporated communities through a condominium conversion process; the County states that implementation went into effect April 4, 2026, and the guidance does not bypass tentative parcel-map or tentative-map processes.
    • For properties with ADU condominiums, effective September 18, 2026, the County requires a right-of-first-refusal contract, an owner-occupancy affidavit for new buyers, and a defined-period public posting and primary-residence disclosure.

    maximum attached ADU area: <= 1200 square feet (also generally limited to 50 percent of the single-family dwelling area, subject to stated exceptions) · maximum detached ADU area: <= 1200 square feet (size does not depend on single-family dwelling size) · maximum JADU area: <= 500 square feet · AB 1033 implementation effective date: 2026-04-04 (separate sale of ADUs through condominium conversion) · ADU condominium local criteria effective date: 2026-09-18 (right of first refusal, owner-occupancy affidavit, and public-posting requirements)

    “An ADU or JADU can be located on a residentially zoned property that has an existing single-family residence.”
  • Who permits septicCounty

    County regulation and permitting of onsite wastewater treatment systems in unincorporated San Diego County and in municipalities that have formally delegated authority to the County.

    • The County LAMP implements statewide OWTS baseline requirements under a Regional Water Quality Control Board-approved local program.
    • The County chapter also applies within a jurisdiction where authority has been delegated through a specific municipal ordinance, memorandum of understanding, or another appropriate mechanism.
    • The cited chapter does not itself establish County DEHQ authority throughout every incorporated municipality absent such delegation.
    “This chapter is applicable to OWTS in the unincorporated areas of San Diego County”
  • Septic permitRequired

    Installing, constructing, reconstructing, repairing, adding to, modifying, connecting to, or destroying an OWTS or other sanitation facility authorized under the County chapter.

    • A permit issued by the Director is required before the covered work begins.
    • A separate application and permit are required for each installation, modification, or destruction.
    • The application must include a scaled system diagram and sufficient information to demonstrate compliance with the County chapter and LAMP.
    • An OWTS installation permit requires proof of a suitable site evaluation, potable water from a public water purveyor or approved domestic well, and a building-permit application.
    • The property grading must be completed and inspected before an OWTS permit is issued.
    • No permit may issue if site or public-health conditions are unsuitable or would risk contamination or an unsanitary condition.
    • The chapter applies to unincorporated areas and delegated municipal jurisdictions; it does not establish universal County authority in all incorporated cities.
    “No person shall install, construct, reconstruct, repair, add to, modify, connect to, or destroy an OWTS [...] without first obtaining a permit issued by the Director.”
  • Septic inspectionRequired

    Installation inspection and finalization of an OWTS installation permit in the County program.

    • After installation is complete, the permittee must give DEHQ at least 24 hours' advance notice that the system is ready for inspection.
    • Unless DEHQ authorizes otherwise, the OWTS installation may not be backfilled before DEHQ inspects and approves it.
    • The installation permit is finalized only after inspection verifies that the OWTS was installed as approved and permitted and meets all minimum requirements.
    • Corrections require a reinspection request within 10 business days.
    • Local land-use agencies typically require completion of all OWTS installation inspections and DEHQ finalization before issuing an occupancy permit.
    • The LAMP scope is unincorporated areas and jurisdictions with delegated authority.

    advance inspection notice: >= 24 hours (unless otherwise authorized by DEHQ) · reinspection request deadline: <= 10 business days (when installation deficiencies are identified)

    “Unless otherwise authorized by DEHQ, no person shall backfill, or cause another person to backfill, an OWTS installation before DEHQ inspects and approves the work.”
  • Off-grid sanitationAllowed (with conditions)

    Use of an onsite wastewater treatment system or other approved sanitation facility where public sewer is unavailable under the County OWTS chapter.

    • When public sewer is unavailable because the sewer-availability conditions are not satisfied, the building must connect to an approved OWTS or other sanitation facilities approved by the Director.
    • The system is approved only if it received all permits required by the County code when installed or modified.
    • The Director determines the required system after considering area, soil porosity, groundwater level, and population density.
    • The OWTS must be designed to receive and dispose of all sewage and liquid waste from the building served.
    • Improper disposal outside an approved public sewer, approved OWTS, or authorized sanitation facility is unlawful.
    • The cited County chapter applies in unincorporated areas and delegated municipal jurisdictions.
    “shall be connected to an approved OWTS, or other sanitation facilities approved by the Director.”
  • Well permitRequired

    Installation or modification of water wells within San Diego County.

    • DEHQ regulates water-well design, construction, modification, and destruction throughout San Diego County.
    • Well standards identified by the County apply.
    • Well Completion Reports must be submitted to DEHQ within 60 days after completing the work.
    • For permits approved on or after July 1, 2026, failure to submit the completion report within 180 days of completion prevents new permits from being issued to the driller or consultant until overdue reports are received.
    • If a well has not been constructed within the first 120 days after permit approval, the applicant may request a one-year extension.

    well completion report deadline: 60 days after completing work · permit-approval effective date for 180-day enforcement policy: 2026-07-01 · construction extension request window: 120 days after permit approval (applicant may request a one-year extension)

    “The installation or modification of wells within San Diego County requires owners to obtain a permit”
  • Mandatory utility hookupConditional

    Sewer connection requirements for buildings constructed or reconstructed where public sewer is available under the County OWTS chapter.

    • Connection to public sewer is required when the property abuts a public sewer or a public sewer is within 200 feet of the building.
    • The property must be within the sewer district or annexation to the sewer district must be completed.
    • No easement through adjacent property may be necessary to complete the connection.
    • The replacement-OWTS exception applies when connection fees and construction costs exceed twice the total cost of the OWTS repair and the replacement OWTS meets the chapter and LAMP requirements.
    • When public sewer is unavailable because one or more conditions are not satisfied, the building must connect to an approved OWTS or other sanitation facilities approved by the Director.
    • The cited County chapter applies in unincorporated areas and delegated municipal jurisdictions.

    public sewer distance threshold: <= 200 feet (measured from the building) · replacement OWTS cost exception: > 2 times repair cost (connection fees and construction costs must be greater than twice the total OWTS repair cost)

    “shall be connected to a public sewer if:”
  • Agricultural exemptionConditional

    County Groundwater Ordinance requirements for specified Major Use Permits and Major Use Permit modifications involving agricultural and ranch support structures or new or expanded agricultural land uses in San Diego County.

    • The exemption applies only to the specified Major Use Permits or Major Use Permit modifications listed in Section 67.750(b).
    • Agricultural and ranch support structures must be used in the production, storage, or processing of food, fiber, and flowers; examples include roadside stands, barns, sheds, packing houses, and greenhouses.
    • The exception does not apply to feed lots.
    • New or expanded agricultural land uses include changes in commodities produced on the property, operations performed upon those commodities, and development of additional irrigated acreage, unless accompanied by subdivision.
    • The exemption does not supersede or limit any other applicable law or regulation, including the California Environmental Quality Act.
    • Agricultural and ranch support structures do not include commercial exportation of groundwater for resale outside the basin.
    • A proposed subdivision exempt from filing a tentative map or tentative parcel map is not subject to the ordinance unless it also involves a General Plan or Specific Plan adoption or amendment, a zoning reclassification, or a Major Use Permit or modification thereof.
    “The following Major Use Permits or Major Use Permit modifications are exempt from this ordinance: (1) Those involving the construction of agricultural and ranch support structures used in the production, storage, or processing of food, fiber, and flowers, including but not limited to roadside stands, barns, sheds, packing houses, and greenhouses, except that this exception does not apply to feed lots. (2) Those involving new or expanded agricultural land uses, including but not limited to changes in commodities produced on the property, operations performed upon such commodities, and development of additional irrigated acreage on the property unless accompanied by subdivision.”
  • Subdividing landRegulated (with conditions)

    Subdivision of land in unincorporated San Diego County, including agricultural subdivisions within County Agricultural Preserves subject to Land Conservation Contracts.

    • An agricultural subdivision may not be approved with lots smaller than the minimum lot size specified in the Land Conservation Contract, in addition to Government Code section 66474.4 limitations.
    • Access roads must meet specified minor-subdivision access standards.
    • Required improvements include private-road grading and improvement, drainage and erosion-control facilities, and water-supply pipelines, fire hydrants, and connections as required by the Planning Commission or Board.
    • For agricultural subdivisions with parcels of 20 acres or more, all improvement requirements in subsection 81.410(c)(1) apply.
    • The ordinance lists amendments effective through May 18, 2018.

    minimum agricultural-subdivision lot size: minimum lot size specified in Land Conservation Contract (subject also to Government Code section 66474.4)

    “no tentative map for an agricultural subdivision shall be approved if it proposes lots smaller than the minimum lot size specified in the contract.”
  • Driveway accessLimited

    Driveways and driveway approaches associated with development in unincorporated San Diego County, especially work in public rights-of-way or County easements.

    • Improvement plans are generally required for improvements in public rights-of-way, County-dedicated easements, and certain private road easements.
    • Driveway and approach work may be treated as a minor improvement when allowed by County staff.
    • A single-family residence with a building permit may construct a concrete driveway in the public right-of-way without an improvement plan prepared by a licensed civil engineer if it meets County design criteria.
    • Private driveway self-certification is limited to qualifying projects; the County page states that the full requirements are in the Rules handout.
    “The County of San Diego allows for private driveways to be done under the self-certification process. The full list of requirements can be found in the Rules handout.”
  • Permit feesPublished (with conditions)

    Building permits and applications processed by San Diego County Planning & Development Services for projects in the unincorporated areas of San Diego County.

    • The schedule is effective July 10, 2026.
    • Fees must be paid to Planning & Development Services for processing the listed permits and applications.
    • Every permit is different; applicants must review the linked information, handouts, and forms to determine which fees might apply.
    • For a project not specifically listed in the building-construction or street-naming and addressing fee tables, the fee is calculated based on valuation.
    • The published schedule includes separate plan-review and permit-fee columns and contains permit-type-specific fees and per-square-foot charges.

    schedule_effective_date: 2026-07-10 · schedule_revision_date: 2026-07-06 · example_permit_type: Single Family Dwelling/Duplex · example_plan_review_fee: $2,310 + $0.357/sf USD · example_permit_fee: $2,547 + $0.222/sf USD

    “PDS 613 REV.: 07/06/2026 PAGE 1 of 7 (Effective 07/10/2026) The following fees shall be paid to the Planning & Development Services for the processing of the following permits and applications: SCHEDULE OF BUILDING CONSTRUCTION PERMIT FEES PERMIT TYPE FY 26/27 Plan Review Fee Permit Fee Single Family Dwelling/Duplex $2,310 + $0.357/sf $2,547 + $0.222/sf”
    One more reviewed finding on this topic
    • Variable (with conditions) — Building permit fees for residential and commercial structures in unincorporated San Diego County.
      “This section provides information on many of the fees associated with obtaining building permits. Every permit is different, so please review the information linked here and the handouts and forms linked from this page to determine which fees might apply.”
  • Permit processPublished (with conditions)

    Residential and commercial building permit processing by the County Building Services Division in unincorporated San Diego County.

    • The County provides in-person processing at the Permit Center and online services for applying for simple building permits, checking permit status, scheduling inspections, and paying fees.
    • The County assigns a Permit Record ID and requires applicants to meet each project condition before permit issuance.
    • Conditions may include Fire District Approval, Flood Control, Septic Review, and Driveway Review.
    “We will assign your project a Permit Record ID. It will include requirements for your project called Conditions of Approval. You must meet each condition before we issue your permit.”

California rules that apply here

  • Owner-builder exemptionAvailable (with conditions)

    Exemption from California contractor-licensing chapter for an owner-builder who builds or improves a structure on the owner’s property; this does not itself establish exemption from local building permits, inspections, or other code requirements.

    • For work personally performed by the owner or performed by the owner’s employees, none of the improvements may be intended or offered for sale, and employee compensation must be wages as their sole compensation.
    • For work directly contracted to licensed trade contractors, the owner must directly contract with licensees duly licensed for the respective trades.
    • For single-family residential structures under the licensed-contractor arrangement, no more than four structures may be intended or offered for sale in a calendar year; this limitation does not apply if the owner contracts with a general contractor for construction.
    • For a homeowner improving a principal residence or its appurtenances, the work must be performed before sale, the homeowner must have actually resided in the residence for the 12 months before completion, and the homeowner must not have used this exemption on more than two structures more than once during any three-year period.
    • A nonprofit corporation may qualify when assisting an owner-builder participating in a mutual self-help housing program.
    • Sale or offering for sale within one year after completion creates a rebuttable presumption that the structure was undertaken for sale; sale or offering for sale of five or more structures within one year creates a conclusive presumption.
    • This is a contractor-licensing exemption and should not be treated as a building-permit exemption.

    single-family structures intended or offered for sale: <= 4 structures per calendar year (Does not apply if the owner contracts with a general contractor for construction.) · prior residence occupancy: >= 12 months before completion (Applies to the principal-residence homeowner exemption.) · owner-builder exemption use: <= 2 structures during any three-year period (The statute states the homeowner has not availed himself or herself of the exemption on more than two structures more than once during any three-year period.) · sale presumption period: 1 year after completion (Sale or offering for sale creates a rebuttable presumption; five or more structures creates a conclusive presumption.) · conclusive-presumption threshold: >= 5 structures within one year after completion (Structures sold or offered for sale by the owner-builder.)

    “This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
    3 more reviewed findings on this topic
    • Conditional — Owners performing or contracting for construction, alteration, repair, improvement, or remodeling of property in San Diego County, subject to California contractor-licensing exemptions.
      “An owner-builder is exempt from licensure, but there are limitations. A license is not required if: The owner-builder does the work themselves or through their own employees with wages as their sole compensation and the structure(s) is/are not intended for sale.”
    • Conditional — Owners who build or improve structures on their own property, and homeowners improving their principal residence or appurtenances, subject to Business and Professions Code section 7044.
      “(a) This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
    • Available (with conditions) — California contractor-licensing requirements for an owner who builds or improves a structure on the owner’s property; this is not stated as an exemption from building permits, inspections, or other code requirements.
      “This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
  • Building code adoptedAdopted (with conditions)

    California Building Standards Code, California Code of Regulations, Title 24, including the 2025 California Building Code and related parts, for buildings and structures subject to the state code.

    • The 2025 California Building Standards Code applies to buildings and structures with a permit application date on or after January 1, 2026.
    • The applicable local building department or enforcing agency determines how the permit application date is established in a specific jurisdiction.
    • The code includes multiple parts, including the California Building Code, California Residential Code, Existing Building Code, Electrical Code, Mechanical Code, Plumbing Code, Energy Code, Wildland-Urban Interface Code, Fire Code, and Green Building Standards Code.

    effective date: 2026-01-01 · permit application date: >= 2026-01-01

    “The 2025 California Building Standards Code (CBSC), California Code of Regulations (CCR), title 24, will become effective on January 1, 2026, as a result of the 2024 Triennial Code Adoption Cycle. [...] The 2025 CBSC applies to all buildings and structures with a permit application date on or after January 1, 2026.”
    One more reviewed finding on this topic
    • Adopted — California statewide building standards, including residential construction subject to Title 24 of the California Code of Regulations.
      “Except as otherwise specifically provided by law, the building standards adopted and submitted by the department for approval [...] shall be adopted by reference”
  • Minimum dwelling sizeSpecified

    Efficiency units permitted by a California city, county, or city and county.

    • The local jurisdiction must adopt an ordinance permitting the efficiency unit.
    • Occupancy is limited to no more than two persons.
    • The unit may have partial kitchen or bathroom facilities as specified by the local ordinance.
    • All other applicable minimum standards under Health and Safety Code Part 1.5 continue to apply.

    minimum floor area: >= 150 square feet · maximum occupancy: <= 2 persons

    “Notwithstanding Sections 17922, 17958, and 17958.5, a city, county, or city and county may, by ordinance, permit efficiency units for occupancy by no more than two persons which have a minimum floor area of 150 square feet and which may also have partial kitchen or bathroom facilities, as specified by the ordinance.”
  • Camping on your landLimited

    Camping in units operated by the California Department of Parks and Recreation statewide.

    • Camping is confined to areas designated for that purpose.
    • Occupancy by the same persons, equipment, or vehicles is generally limited to 30 days in any calendar year in that unit.
    • The Department may establish shorter or longer occupancy limits.
    • When a shorter seasonal limit applies, the camper must vacate the campsite and may not reregister in the unit until 48 hours have expired, measured from 12:00 noon on the checkout day to 12:00 noon on the second day following.
    • A district superintendent may permit one-night camping in a day-use area or portion of one, subject to Department-established fees and vehicle limitations; occupants must vacate by 9:00 a.m. the following morning.
    • California State Parks' current reservation policy states that each campground has a consecutive-night limit, requires a 48-hour absence after that limit, and generally has a 30-night annual maximum, subject to individual park policies.

    general annual occupancy limit: 30 days per calendar year per unit (The Department may establish shorter or longer limits of occupancy.) · return interval after shorter seasonal limit: 48 hours (Measured from 12:00 noon of the checkout day to 12:00 noon of the second day following.) · one-night camping in day-use area: 1 night (Only if permitted by the district superintendent; occupants must vacate by 9:00 a.m. the following morning.)

    “Occupancy by the same persons, equipment, or vehicles of any camping facility is limited to a total of 30 days in any calendar year in that unit.”
    One more reviewed finding on this topic
    • Allowed (with conditions) — Temporary camping in California special occupancy parks, including parks containing recreational vehicles, tents, or camping cabins.
      ““Special occupancy park” means a recreational vehicle park, temporary recreational vehicle park, incidental camping area, or tent camp.”
  • Campground & park staysLimited

    Occupancy and use of manufactured homes and mobilehomes in California mobilehome parks and other locations subject to HCD jurisdiction.

    • HCD administers titling and registration for manufactured homes and mobilehomes.
    • HCD-inspected mobilehome parks are subject to health and safety enforcement where local government has not assumed enforcement.
    • Manufactured/mobilehome park regulations address construction, use, maintenance, and occupancy.
    • Separate local land-use, building, fire, health, and utility requirements may apply.
    “MHs may be occupied outside or inside of mobilehome parks and installation and approval for occupancy is governed by the Mobilehome Parks Act (MPA), HSC Sections 18200, et seq., and Title 25, CCR Sections 1000, et seq.”
    2 more reviewed findings on this topic
    • Limited — RV and trailer camping at Silver Strand State Beach Campground in the San Diego Coast District.
      “Camping Stay Limits: Applies to persons, equipment, or vehicles and any combination thereof [...] Maximum stay of 30 days per calendar year [...] Maximum 7 consecutive days during peak season (May 15 – September 15) [...] Maximum 14 consecutive days during non-peak season”
    • Limited — Occupancy and use of recreational vehicles in California special occupancy parks and designated RV sections of mobilehome parks.
      “Unless otherwise allowed by a local ordinance, RVs generally may be occupied only in mobilehome parks or special occupancy parks governed by the Mobilehome Parks Act”
  • county zoning authorityGeneral

    California county legislative bodies' authority to adopt zoning ordinances regulating buildings, structures, land uses, lots, yards, open space, lot coverage, intensity of use, parking, loading, and setbacks within county jurisdiction, including unincorporated areas.

    • The authority is exercised pursuant to Government Code Chapter 4, Zoning Regulations.
    • The statute separately authorizes city legislative bodies; incorporated municipalities may exercise their own zoning authority.
    • Government Code Section 65850 also lists authority to regulate signs and billboards, building and structure location, height, bulk, number of stories, and size, lot and open-space size and use, lot coverage, intensity of land use, offstreet parking and loading, and building setback lines.
    • The cited section states it was amended by Stats. 2017, Ch. 376, Sec. 1, effective January 1, 2018.
    “The legislative body of any county or city may, pursuant to this chapter, adopt ordinances that do any of the following:”
  • county building authorityGeneral

    California counties administering and enforcing state building standards through county building departments, including residential construction in unincorporated areas.

    • Each county must maintain building standards and state building regulations in the office of the building official responsible for administration and enforcement of state building standards.
    • The statewide Title 24 standards apply subject to statutory exceptions and any authorized local amendments or local requirements.
    • The cited HCD bulletin concerns the 2019 California Building Standards Code and its July 1, 2021 supplement; later code editions may supersede those particular edition dates.
    “These codes shall be maintained in the office of the building official responsible for the administration and enforcement of state building standards”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

  • Short-term rentals — Short-term rental land-use authorization in unincorporated San Diego County.

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Water rights & wells in San Diego County

Whether a new home can legally get its own water here — the sub-state groundwater regime, from California’s water agency.

Adjudicated — rights fixed

Water rights here have been fixed by a court. New supply effectively means acquiring an existing right.

Household wellPermit required — restricted

California requires no STATE permit for a domestic well — wells are permitted by the county — but under SGMA a Groundwater Sustainability Agency can meter or restrict new wells in medium/high-priority and critically overdrafted basins, and Executive Order N-7-22 requires counties in those basins to get GSA verification that a new well is consistent with the Groundwater Sustainability Plan before permitting.

Limit: 2 acre-feet/year de minimis under SGMA (Water Code §10721(e)) — largely exempt from GSA metering/fees

California DWR / State Water Board — SGMA de minimis & EO N-7-22 Action 9 FAQ ↗

Hybrid state (appropriation + riparian). Groundwater rules change and basin boundaries follow the aquifer, not the county line — confirm current well and appropriation rules with the California state water agency before you buy or drill.Groundwater governance as of Jul 2026, cited to each administering agency.

Living off-grid in San Diego County, California

Is San Diego County a good place to live off-grid or homestead?

San Diego County scores 41/100 on the Bolthole Index, a marginal county profile. Watch-outs: about 569,378 people within 15 miles and higher long-term carry cost.

Do you need a building permit in San Diego County, California?

San Diego County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by San Diego County Department of Environmental Health and Quality. Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

Can you live in an RV or tiny home on your land in San Diego County?

Living in an RV on your own land in San Diego County is limited to specific cases: Use or occupancy of trailer coaches, including recreational vehicles treated as trailer coaches, in unincorporated San Diego County. Use or occupancy must be authorized by the County Zoning Ordinance. A valid, unexpired trailer coach installation permit issued and approved by the Director of Planning and Land Use is generally required. A tiny home is limited to specific cases. Confirm with the county before relying on it.

How much does land cost in San Diego County, California?

Land in San Diego County runs about $36,053 per acre, based on the latest county data.

What is the water situation in San Diego County?

San Diego County gets about 13" of rain a year, with severe drought in roughly 27.9% of years. On water rights, San Diego County lies in the Borrego Springs Subbasin — Critically Overdrafted (Adjudicated) — Stipulated adjudication (2020) with a ~74% pumping reduction to 2040; extractions capped/allocated by a watermaster; new appropriation effectively closed..

How remote is San Diego County?

A typical private-land location has about 569,378 people within 15 miles and 24,360,248 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

Off-grid gear

Going off-grid in San Diego County means bringing your own water and power. The kit we’d start with:

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How San Diego compares in California

Compare side-by-side →See all 58 California counties ranked →