Kings County ADU Requirements (2026)

Size limits, setbacks, required documents, and fees for building an ADU in Kings County, California — covering unincorporated county areas, Hanford, and Lemoore.

By set4 ResearchLast reviewed April 1, 2026

Who this guide is for

If you're planning to build an ADU in Kings County — in unincorporated county land, the City of Hanford, Lemoore, or Corcoran — this guide covers the key requirements before submitting plans.

Kings County is a compact, predominantly agricultural Central Valley county. This guide focuses on unincorporated Kings County; city rules may vary.

Jurisdiction overview

JurisdictionPlanning authorityNotes
Unincorporated Kings CountyKings County Planning DepartmentAgricultural county, rural lots common
City of HanfordHanford Community DevelopmentCounty seat, largest city
City of LemooreLemoore Building DivisionNear NAS Lemoore; base influence area considerations
City of CorcoranCorcoran Community DevelopmentSmaller city, contact for standards

For properties inside a city, apply through that city's building department — not the county.

Size limits

ADU typeMaximum size
Detached ADUUp to 1,200 sq ft
Attached ADUUp to 50% of existing living area, or 1,200 sq ft — whichever is less
JADU (Junior ADU)Up to 500 sq ft, within existing structure
Garage conversionFull existing garage area

A single-family property may have both one ADU and one JADU.

Setback requirements

SetbackRequirement
Side and rear (new construction)4 ft minimum (state law)
FrontPer underlying zoning district
Conversion of existing structureNo setback required if structure is maintained
Height limit (detached)16 ft

Rural parcels in unincorporated Kings County may have larger front setbacks based on underlying agricultural or residential zoning. Confirm with the county before siting your ADU.

Required documents

A complete ADU application for unincorporated Kings County typically requires:

  1. Permit application form — Kings County Planning Department
  2. Site plan — parcel boundaries, dimensions, setbacks, existing structures, proposed ADU location, access, utilities
  3. Floor plan — dimensioned layout, room labels, fixtures, doors, egress
  4. Elevations — all four sides, heights, materials, roofline
  5. Structural plans — foundation, framing, lateral resistance
  6. Title 24 energy compliance — CF1R residential energy forms
  7. CalGreen checklist — mandatory green building requirements
  8. Proof of ownership — deed or title report
  9. Septic/well evaluation — required for parcels not on public sewer/water (common in unincorporated areas)

Fees

California limits ADU fees:

  • No impact fees for ADUs under 750 sq ft
  • Proportional impact fees for ADUs 750 sq ft and above
  • No school fees for ADUs

Kings County is one of California's smaller, lower-cost counties. As of 2026, expect:

  • Building permit fee: $1,000–$3,000 depending on project valuation
  • Plan check fee: Typically 65% of building permit fee
  • Septic evaluation/connection fees: Vary by site

City fees (Hanford, Lemoore) have their own schedules — contact the applicable city for current rates.

NAS Lemoore Base Influence Area

If your property is within the Kings County area near Naval Air Station Lemoore, there may be:

  • Noise compatibility zones that restrict certain residential uses or require sound attenuation
  • Accident Prevention Zones (APZs) that limit building density near the runway approaches
  • Building height restrictions in the approach paths

Check the Kings County General Plan Land Use Element and contact county planning to confirm your parcel's status before proceeding.

Common reasons ADU plans are sent back

Based on patterns from Kings County and similar Central Valley jurisdictions:

  • Septic/well documentation missing for rural parcels
  • Site plan missing property line dimensions, north arrow, or utility locations
  • No Title 24 energy forms included
  • Structural details incomplete — missing connection details, no load path
  • Floor plan not dimensioned — rooms must show dimensions
  • Elevations missing one or more sides
  • No construction type or occupancy listed on permit application

A pre-check catches these issues before you submit to the county building department.

Sources

Frequently asked questions

Yes. California state law (AB 2221, SB 897) requires Kings County and all its cities to allow ADUs on residentially-zoned properties. The county handles permits for unincorporated areas; the cities of Hanford, Lemoore, and Corcoran have their own building departments.

ADU regulations apply to residentially-zoned parcels. Kings County has extensive agricultural land — if your parcel is zoned agricultural with an existing legal dwelling, contact the county planning department to confirm whether an ADU is permitted. Agricultural employee housing has separate provisions under state law.

California law requires the jurisdiction to act on complete ADU applications within 60 days. Kings County is a smaller county with lower application volume, which can mean faster turnaround — but only if your application is complete from the start. Missing documents or incomplete plans trigger correction notices that pause the clock.

Properties near NAS Lemoore may be subject to noise compatibility zones and Accident Prevention Zones (APZs) that restrict building density and use. If your property is in or near the Base Influence Area, check with Kings County planning before designing your ADU — certain uses or building heights may be restricted.

Unincorporated Kings County follows state minimum ADU standards without additional design guidelines. Cities may impose compatibility requirements (materials, colors, or roof pitch to match the primary structure). Check with the applicable city if you're inside an incorporated area.

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