Bolthole Index

Orange County, California

Building permits, zoning and land rules in Tustin, California

Inside Tustin, California, the City Building Division provides plan review, building permit and inspection services, and the City enforces its own zoning and residential development standards.12 Orange County Environmental Health handles well permits in Tustin, but we could not confirm which office permits septic systems inside city limits.3

At a glance

Building permits
City Building Division provides plan review, permit and inspection services1
Building code
City enforces the 2025 California Building Standards Codes4
Zoning
City zoning districts and development standards apply inside Tustin2
R1 minimum lot
7,200 square feet per family unit and 60 feet wide5
Owner-builder
Allowed conditionally; declaration and verification form required6
Well permit
Required through Orange County Environmental Health3
Septic inside city
Issuing authority not confirmed; ask the City Building Division before planning a system1

Who to call

Building permits

City of Tustin Building Division

Building permit information, plan review and inspections inside Tustin city limits

714-573-3130

[email protected]

300 Centennial Way, Tustin, CA 92780

Online permits →

Planning & zoning

City of Tustin Planning Division

Zoning, land-use review and development questions inside Tustin city limits

714-573-3140

[email protected]

300 Centennial Way, Tustin, CA 92780

Online permits →

Well permits

Orange County Environmental Health Well Permitting

Permits for constructing, reconstructing or destroying wells inside Tustin

714-433-6287

[email protected]

Contact details are copied from each office’s official page and were checked against it on October 10, 2026.

Off-grid gear

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

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Do you need a building permit in Tustin, California?

Building work inside Tustin goes through the City Building Division, which provides plan review, building permit and inspection services.1 Commercial buildings and tenant improvements require a permit application, with Planning Division approval before plans go to Building; electrical, mechanical, plumbing and grading reviews can require separate building-related permits and fees.7 Tustin enforces the 2025 California Building Standards Codes for applications submitted on or after January 1, 2026.4 Ask the Building Division whether a permit is required for a particular residential repair, accessory structure or alteration before work begins.1

Who issues building permits in Tustin, and how do you reach them?

The City of Tustin Building Division is the building permit office for property inside city limits.1 Its counter is at 300 Centennial Way, Tustin, CA 92780; call 714-573-3130 or email [email protected].1 The separate Planning Division handles zoning and land-use questions at the same address; call 714-573-3140 or email [email protected].8 Orange County's development-services rules and permit counter described for unincorporated Orange County do not replace these City offices for a Tustin parcel.9

Does Tustin have zoning, and what does it mean for lots and setbacks?

Yes. Tustin administers its own zoning districts and residential development standards inside city limits, and specific plans can modify the general standards.2 In the R1 Single-Family Residential District, the general table sets a minimum lot area of 7,200 square feet per family unit and a minimum width of 60 feet.5 The R1 standards set a 20-foot front yard, 5-foot interior side yard, 10-foot corner side yard and 5-foot rear yard, together with at least 1,000 square feet of clear usable open space in the rear third.10 R1 lot coverage is capped at 40 percent and building height at 30 feet.1112 Confirm the parcel's district and any specific plan with the Planning Division before designing.8

Can you live in an RV, mobile home or tiny home in Tustin?

We could not confirm a Tustin rule allowing someone to live in an RV or tiny home on an ordinary private lot. Ask the Planning Division before buying or placing either one.8 Tustin's MHP Mobile Home Park District is narrower: mobile-home parks and travel-trailer parks may be permitted there with a Conditional Use Permit and compliance with district development standards.13 California treats a tiny home as a residential structure that needs the applicable state or local approval before occupancy; its legal pathway depends on whether it qualifies as a code-built dwelling, manufactured home, factory-built housing, recreational vehicle, park trailer or camping cabin.14

How do septic permits and well permits work inside Tustin?

We could not confirm the office that issues permits for a new or replacement septic system inside Tustin city limits. The City's fee schedule lists a private sewage-disposal-system fee, but that alone does not establish the operative approval process or responsible office.15 Ask the Building Division whether the parcel must connect to public sewer and which agency must approve any onsite system.1 Wells are clearer: Orange County Environmental Health enforces the county well ordinance in Tustin, and a well permit is required before constructing, reconstructing or destroying a well.3 Call 714-433-6287 or email [email protected] for the well process.16

Building a home in Tustin: the steps, in order

  1. Confirm that the parcel is inside Tustin and ask the Planning Division for its zoning district and any applicable specific plan.28
  2. Check district lot area, coverage, height and setbacks before commissioning final plans.510
  3. Confirm sewer service or the septic approval path with the Building Division, and contact Orange County Environmental Health if a well is proposed.116
  4. Submit the plans for City review and pay the required building permit fees after approval.17
  5. If acting as owner-builder, complete the required declaration and verification form before permit issuance.6
  6. Schedule City inspections as construction or grading reaches the required phases.18

What stays with Orange County, and what should you check before buying?

Inside Tustin, the City handles zoning, building permit review and inspections, while Orange County Environmental Health administers well permits.23 Work in the public right-of-way, including a driveway or water or sewer connection, requires a City encroachment permit through the Engineering Division.19 New construction and substantial improvements in a Special Flood Hazard Area must meet Tustin's flood-resistant construction rules.20 Before buying, ask Planning about the zoning district and specific plan, ask Building about sewer or septic service, check flood status, and confirm that any proposed driveway can receive the required City approval.81

Watch-outs

  • We could not confirm which office permits new or replacement septic systems inside Tustin; ask the City Building Division before treating onsite sewage as an option.1
  • Specific plans can modify Tustin's general residential development standards, so the base zoning table may not be the final rule for a parcel.2
  • Driveways and utility connections within the public right-of-way require a City encroachment permit.19

Sources

  1. City of Tustin Building Division (tustinca.org)
  2. Residential Site Development Standards (Tustin), quoted and re-checked
  3. Water and Well Permitting Program (Tustin), quoted and re-checked
  4. Governing Codes & Ordinances (Tustin), quoted and re-checked
  5. Residential Site Development Standards (Tustin), quoted and re-checked
  6. Owner-Builder Permit Application Package (Tustin), quoted and re-checked
  7. Commercial Buildings and Tenant Improvements (Tustin), quoted and re-checked
  8. City of Tustin Planning Division (tustinca.org)
  9. Building Permit Information, quoted and re-checked
  10. Residential Site Development Standards (Tustin), quoted and re-checked
  11. Residential Site Development Standards (Tustin), quoted and re-checked
  12. Residential Site Development Standards (Tustin), quoted and re-checked
  13. Mobile Home Park District (MHP) (Tustin), quoted and re-checked
  14. Information Bulletin 2016-01 Tiny Homes, quoted and re-checked
  15. 2025-26 Comprehensive Schedule of Fees (Tustin), quoted and re-checked
  16. Orange County Environmental Health Well Permitting (ochealthinfo.com)
  17. Permits Process (Tustin), quoted and re-checked
  18. Permits Process (Tustin), quoted and re-checked
  19. Development Review (Tustin), quoted and re-checked
  20. Provisions for Flood Hazard Reduction (Tustin), quoted and re-checked

Written October 10, 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.

Answers from the rulebook for Tustin

Tustin’s own rules

  • Building permitRequired

    Commercial buildings and tenant improvements inside Tustin city limits.

    • Planning Division approval is required before submitting plans to the Building Division.
    • Separate permits and fees are required for electrical, mechanical, plumbing, and grading plan check and permits.
    “All projects must have a permit application. California law requires that every permit applicant supply specific information and make certain declarations regarding the proposed work.”
  • Owner-builder exemptionConditional

    Property owners applying for an owner-builder construction permit inside Tustin city limits.

    • The property owner must complete, sign, and return the owner-builder form before permit issuance.
    • The owner-builder becomes the legally and financially responsible party for the construction activity.
    • An owner-builder verification form is required for all owner-builder projects.
    “If the property owner is doing all the construction work or will be hiring workers without employing a licensed contractor, it is an “owner/builder” project and the owner builder declaration must be signed.”
  • Building code adoptedAdopted

    Building work within Tustin city limits.

    • The City page states that the 2025 California Building Standards Codes are enforced effective January 1, 2026.
    • Ordinance No. 1569 is identified on the page as proposed to adopt and amend the 2025 code with certain appendices and supplemental regulations.
    • All new plan review applications submitted on or after January 1, 2026 must comply with the referenced code editions and Ordinance No. 1569.
    “If you are a City of Tustin property owner or an architect, engineer, designer, or contractor that performs work within the City, please be advised that the City will be enforcing the following 2025 California Building Standards Codes, effective on January 1, 2026.”
  • InspectionsRequired

    Construction or grading projects inside Tustin city limits during applicable phases of work.

    • Inspection requests require the permit number, project address, and contact name and generally must be made one day in advance.
    • Inspections are performed during various phases of construction or grading.
    “During various phases of construction or grading, Building Division Inspectors must review the work to ensure that it is proceeding consistent with the approved plans and the law.”
  • Local zoningPresent

    Land inside Tustin city limits; Tustin administers its own zoning districts and residential development standards.

    • District-specific standards and applicable specific plans may modify the general residential standards.
    “Site Development Standards for primary residential uses by Zoning District. Site development standards for primary residential uses shall comply with the standards listed in Table 1, unless otherwise noted.”
  • Zoning districtsPublished

    Residential zoning districts inside Tustin city limits.

    • The official code table identifies RA, E4, R1, R2, R3, R4, MHP, and PD residential districts.
    • Specific plans and district-specific provisions may add or modify standards.
    “Table 1: Primary Residential Uses Zoning Minimum Lot Area/Per Family Unit Minimum Lot Width Lot Coverage Building Height Front Yard (1) Interior Side Yard (1) Corner Side Yard (1) Rear Yard (1) RA Residential Agricultural District (Sec. 9221)”
  • Minimum lot sizeSpecified

    Primary residential uses in the R1 Single-Family Residential District.

    • The table states 7,200 square feet per family unit and a 60-foot minimum lot width.

    minimum lot area per family unit: >= 7200 square feet · minimum lot width: >= 60 feet

    “R1 Single-Family Residential District (2) (Sec. 9223) 7,200 sq. ft./7,200 sq. ft. 60 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
    One more reviewed finding on this topic
    • Specified — Primary residential uses in the RA Residential Agricultural District.
      “RA Residential Agricultural District (Sec. 9221) 7,200 sq. ft./7,200 sq. ft. Linear frontage 60 feet/Cul-de-sac frontage 40 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
  • SetbacksSpecified

    Primary residential uses in the R1 Single-Family Residential District.

    • Front yard 20 feet; interior side yard 5 feet; corner side yard 10 feet; rear yard 5 feet, with at least 1,000 square feet of clear usable open space in the rear third of the lot.

    front yard: 20 feet · interior side yard: 5 feet · corner side yard: 10 feet · rear yard: 5 feet (plus no less than 1,000 square feet clear and unobstructed usable open space on rear one-third of lot)

    “R1 Single-Family Residential District (2) (Sec. 9223) 7,200 sq. ft./7,200 sq. ft. 60 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
    One more reviewed finding on this topic
    • Specified — Primary residential uses in the RA Residential Agricultural District.
      “RA Residential Agricultural District (Sec. 9221) 7,200 sq. ft./7,200 sq. ft. Linear frontage 60 feet/Cul-de-sac frontage 40 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
  • Lot coverageSpecified

    Primary residential uses in the R1 Single-Family Residential District.

    • Maximum lot coverage is 40 percent.

    maximum lot coverage: <= 40 percent

    “R1 Single-Family Residential District (2) (Sec. 9223) 7,200 sq. ft./7,200 sq. ft. 60 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
    One more reviewed finding on this topic
    • Specified — Primary residential uses in the RA Residential Agricultural District.
      “RA Residential Agricultural District (Sec. 9221) 7,200 sq. ft./7,200 sq. ft. Linear frontage 60 feet/Cul-de-sac frontage 40 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
  • Building heightSpecified

    Primary residential uses in the R1 Single-Family Residential District.

    • Maximum building height is 30 feet.

    maximum building height: <= 30 feet

    “R1 Single-Family Residential District (2) (Sec. 9223) 7,200 sq. ft./7,200 sq. ft. 60 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
    One more reviewed finding on this topic
    • Specified — Primary residential uses in the RA Residential Agricultural District.
      “RA Residential Agricultural District (Sec. 9221) 7,200 sq. ft./7,200 sq. ft. Linear frontage 60 feet/Cul-de-sac frontage 40 feet 40 percent 30 feet 20 feet 5 feet 10 feet 5 feet, but no less than 1,000 sq. ft. clear and unobstructed usable open space on rear ⅓ of lot”
  • Manufactured homesAllowed (with conditions)

    Manufactured-home occupancy and mobile-home parks in the Tustin MHP Mobile Home Park District.

    • A Conditional Use Permit is required.
    • The MHP district permits mobile home parks and travel trailer parks subject to the district development standards.
    • The MHP table states a minimum five-acre site for a mobile home park, maximum density of ten dwelling units per net acre, maximum height of 30 feet, and maximum lot coverage of 75 percent.

    minimum mobile home park site: >= 5 acres · maximum mobile home park density: <= 10 dwelling units per net acre (public streets excluded) · maximum height: <= 30 feet · maximum lot coverage: <= 75 percent

    “In the Mobile Home Park District (MHP), only the following uses (or uses which in the opinion of the Community Development Director and/or the Planning Commission are similar) may be permitted subject to the issuance of a Conditional Use Permit and the development standards of this Chapter.”
  • Driveway accessLimited

    Driveway work within the public right-of-way inside Tustin city limits.

    • An encroachment permit is required through the City's Engineering Division for work in the public right-of-way.
    • The City directs applicants to use its Citizen Self Service Portal.
    “The Engineering Division is also responsible for the review and issuance of encroachment permits for any work to be performed within the public right-of-way, such as driveways and water and sewer connections.”
  • Building in a floodplainRequired

    New construction and substantial improvements in Special Flood Hazard Areas inside Tustin city limits.

    • New construction and substantial improvements must be anchored against flotation, collapse, and lateral movement.
    • Construction materials and methods must resist or minimize flood damage.
    • In specified flood zones, lowest-floor elevation and professional certification requirements apply.
    • New and replacement water and sanitary sewer systems must minimize or eliminate floodwater infiltration.
    • New or replacement on-site waste-disposal systems must be located to avoid impairment or contamination during flooding.
    “All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.”
  • Permit feesPublished (with conditions)

    Building, sewer-connection, and private sewage-disposal-system permits inside Tustin city limits.

    • The fee schedule is identified as 2025-26.
    • The schedule states that a separate permit is required for each house-sewer connection or extension.
    • Other plan-check, permit, grading, utility, and development-related fees may apply.

    house sewer connection or lateral extension: 35.22 USD (separate permit required for each connection or extension) · private sewage disposal system: 105.6 USD (septic tank and seepage pit or pits and/or drain field)

    “For each private sewage disposal system (septic tank and seepage pit or pits and/or drain field) $105.60”
  • Permit processPublished (with conditions)

    Building permit applications inside Tustin city limits.

    • The City completes plan review before permit issuance.
    • Required fees must be paid to obtain a permit.
    • Permits are generally valid for 180 days unless work is active and progressing.
    • First submittal plan check generally takes approximately 10 working days; subsequent submittals generally take five working days.
    • Expedited plan check is available for a higher fee.

    permit validity: 180 days (unless work is active and progressing) · first submittal plan check: 10 working days (approximately) · subsequent plan check: 5 working days (generally)

    “When The City has completed plan review and determined that the proposed project meets federal, state and local code requirements, a permit may be issued. You or your licensed design professional will be requested to pay required fees to obtain a permit. A permit is valid for 180 days, unless work is active and progressing, in which case the permit will continue to be valid until the project is complete.”

Rules another office applies inside Tustin

Tustin does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • Well permitRequired

    Construction, reconstruction, or destruction of wells inside Tustin city limits; Orange County Environmental Health administers the county well ordinance in Tustin.

    • A Well Permit must be obtained before initiation of work.
    • The source states the county ordinance applies in all cities except Anaheim, Buena Park, Fountain Valley, Orange, and San Clemente; Tustin is not among the listed exceptions.
    “We enforce the Orange County Well Ordinance in the unincorporated areas of the County and in all cities except for Anaheim, Buena Park, Fountain Valley, Orange, and San Clemente.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Tustin or Orange County directly.

  • Certificate of occupancy — Certificate-of-occupancy requirements inside Tustin city limits.
  • Minimum dwelling size — Primary residential dwellings inside Tustin city limits.
  • Tiny homes — Tiny-home occupancy inside Tustin city limits.
  • Accessory dwellings — Accessory dwelling units inside Tustin city limits.
  • Who permits septic — Septic-system permitting and administration inside Tustin city limits.
6 more unanswered
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Mandatory utility hookup
  • Agricultural exemption
  • Short-term rentals

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.

Unanswered questions are usually a sign that Tustin publishes no rule on the point, not that none exists. Orange County’s page lists the county offices to call.

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