Santa Clara County Zoning, Planning & Building Codes

Last reviewed: July 6, 2026

Overview

Santa Clara County’s zoning rules apply only in the County’s unincorporated areas; incorporated cities have their own codes. The County’s zoning ordinance is adopted as Appendix I of the County Ordinance Code and is formally titled the Zoning Ordinance of the County of Santa Clara (§ 1.10.010) . It divides unincorporated land into zoning districts, regulates uses and development standards, and implements the County General Plan (§ 1.10.020–§ 1.10.030) . Start with the Santa Clara County Zoning map to confirm your property’s base district and any combining (“overlay”) districts.

Always check both the base district in Article 2 and any combining district in Article 3—combining districts augment or supersede base rules, and they prevail in case of conflict (§ 1.20.010(D)) .

How Santa Clara County’s code is organized

• The ordinance has five articles. Article 2 is the starting point for base districts; Article 3 contains combining/overlay districts; Article 4 has supplemental standards (including parking and signs); and Article 5 provides procedures and review authorities (§ 1.20.010(B)–(F)) .
• Base districts are grouped as:
  • Rural Base Districts (Chapter 2.20)
  • Urban Residential Base Districts (Chapter 2.30)
  • Commercial & Industrial Base Districts (Chapter 2.40)
  • Special Purpose Base Districts (Chapter 2.50) (§ 1.20.010(C)(1)) .
• Development standards like minimum lot size, setbacks and height live in the Article 2 district chapters; other standards (e.g., parking, signs, nonconformities) are in Article 4 (§ 1.20.010(C)(2), (E)) .

Official zoning maps are maintained by the Planning Office and are incorporated by reference; compliance with the zoning ordinance is mandatory (§ 1.20.060, § 1.20.070) .

Zoning district families

Base districts

• Rural (Ch. 2.20): Includes districts such as AR, HS, and RR and uses slope-density tools for large-lot and hillside development (§ 2.20.040, Table 2.20-4) .
• Urban Residential (Ch. 2.30): Includes districts such as R1, R1E, R2, R3, and hillside variants like RHS; development standards are in Table 2.30-3 (§ 2.30.030) .
• Commercial & Industrial (Ch. 2.40): Districts include CN, CG, OA, ML, MH with property development standards summarized in Table 2.40-2 (e.g., lot coverage and height) and supplemental standards (e.g., landscaping, screening, adjacency buffers) in § 2.40.040 .
• Special Purpose (Ch. 2.50): A1 (General Use), RS (Roadside Services), and Stanford-related OS/F (Open Space & Field Research) and SCA (Special Conservation Areas), each with tailored purposes and limitations (§ 2.50.010) .

Combining (overlay) districts

• Lot Size & Setbacks (Ch. 3.10): Numeric designators (e.g., -6, -8, -10, -1 Ac.) set minimum lot size and setbacks; these supersede base-district setbacks (§ 3.10.030) .
• Viewshed “-d” (Ch. 3.20): The -d1 Santa Clara Valley Viewshed overlay applies tiered review to larger homes and hillside grading visible from the Valley floor (§ 3.20.040) .
• Scenic Roads “-sr” (Ch. 3.30): Imposes design review within 100 ft of designated scenic road ROWs and special sign/setback rules (§ 3.30.030) .
• Historic Preservation “-h” (Ch. 3.50): Allows district-specific use and development standards that supersede the base district and requires approvals for demolition of designated resources (§ 3.50.050–§ 3.50.070) .
• Housing Opportunity Sites “-os” (Ch. 3.75): Restricts development to multi-family and limited mixed-use and sets affordability and procedural standards to implement the Housing Element (§ 3.75.010–§ 3.75.020) .

Explore these tools on the Santa Clara County Overlay Districts page.

Citywide development standards

Where the rules live

• Use allowances and the core development standards (setbacks, height, lot area/coverage) live in Article 2 tables for each family of base districts (§ 1.20.010(C)(2)) .
• Combining districts can replace the normal setbacks/lot sizes (e.g., -10 requires a 10,000 sq ft lot, 25 ft front, 10 ft side, 25 ft rear per § 3.10.030) .
• Commercial/industrial examples: Table 2.40-2 caps lot coverage (e.g., 25% in OA, 40% in ML, 50% in MH) and sets maximum heights (e.g., up to 65 ft subject to rules-of-measurement and ASA flexibility) with landscaping and adjacency protections in § 2.40.040 .
• Hillsides: Building site approval is required on slopes ≥30% in hillside-related districts (R1E, RHS, HS) with detailed submittal and safety/visual standards (Art. 5 of Division C12, e.g., § C12-350.1) .

Measurement and parking

• Setback and height are measured from ultimate right-of-way and per Chapter 1.30 definitions; check rules-of-measurement posted under each table (e.g., Table 2.40-2, “Rules of measurement”) .
• Off-street parking standards are in Chapter 4.30, which applies to new and substantially altered projects and sets continuing obligations to maintain required spaces (§ 4.30.010–§ 4.30.020) .

Other recurring standards

• Landscaping/screening: Industrial yards must be landscaped; outdoor storage must be screened (§ 2.40.040(A)–(B)) .
• Nonconformities: The County retains authority to abate public nuisances even where nonconforming rules may apply (§ 4.50.090) .
• Signage: New or major changes to signs tied to a legally established use can trigger ASA (§ 5.40.020(C)) .

For quick access to dimensional rules across districts, use the Santa Clara County Development Standards guide.

Specific plans & overlays that matter countywide

• Stanford University Community Plan: Drives the purpose and limits of OS/F and SCA special-purpose districts (§ 2.50.010) . Stanford development also has special parking and conformance carve-outs (§ 4.30.020(C)) .
• Habitat Conservation Plan: The Santa Clara Valley HCP/NCCP is adopted by reference and can govern mitigation/coverage for listed species; conditions and fees apply to covered activities (Division C20, e.g., § C20-2) .
• Official Plan Lines: Planned rights-of-way can constrain building locations; no structure may be placed within adopted plan lines (Ch. C12-701–C12-702) .
• Viewshed and Scenic Roads: The -d1 viewshed overlay imposes tiered design controls for larger homes and extensive retaining walls (§ 3.20.040) and -sr requires design review within 100 ft of scenic roads (§ 3.30.030) .
• Historic areas: The -h overlay may impose special use/height/setback/sign rules and Board approvals for demolition of designated resources (§ 3.50.050–§ 3.50.070) . See Santa Clara County Historic Preservation.

Building permits & review

• Who decides what: Table 5.10-1 assigns permits to authorities—e.g., Architecture and Site Approval (ASA) by Zoning Administrator (appeal to PC/Board), Design Review by ZA, Special Permits by ZA, Use Permits by PC, Variances by ZA, and Zoning amendments by the Board (§ 5.10.020) . When multiple approvals are needed, the highest authority can decide them together (§ 5.10.060) .
• ASA: Required where specified in the code (common for commercial/industrial/multifamily, certain signs, slopes ≥30%, and in -h areas) and granted on findings covering traffic, design, landscaping, safety, and plan consistency (§ 5.40.010–§ 5.40.040) .
• Design review: Mandatory in -d, -h, and within 100 ft of scenic roads; the ZA considers visual, environmental, and neighborhood compatibility (§ 5.50.020–§ 5.50.040) .
• Process: Common procedures include pre-application meetings (when required), submittal, fees, environmental review, hearings/notice, timing, and appeals (§ 5.20.010, § 5.20.020, § 5.20.030) . Within a city’s urban service area, additional limits and annexation procedures apply to certain projects (§ 5.20.070) .
• Building permits: No one may perform work requiring a permit without first obtaining it under the County’s building, residential, plumbing, electrical, mechanical, and green codes (Sec. C1-67) . Building is also governed by the California Building Standards Code.

State housing law in Santa Clara County

• ADUs/JADUs: The County implements state ADU law via § 4.10.015 (e.g., ADUs/JADUs appear as permitted or ministerial in district use tables) and includes owner-occupancy rules for JADUs in table notes (e.g., Note 11 in residential/commercial tables) .
• SB 9 (urban lot splits and two-units): The code integrates SB 9 through subdivision and use table notes—e.g., parcels created by an urban lot split under § C12-44 are limited to no more than two total dwelling units per parcel under the Urban Primary Unit framework (notes in Ch. 2.30 tables) .
• Housing Opportunity Sites: The -os overlay designates parcels for multifamily/limited mixed-use with required affordable unit delivery aligned to the Housing Element; the chapter states County housing provisions will be interpreted to be consistent with state housing laws (§ 3.75.010–§ 3.75.020) .
• Density/fair housing compliance: The code expressly prioritizes consistency with state housing laws where conflicts arise (e.g., -os chapter purpose) (§ 3.75.010) . See also our guide to California ADU law.

Source References

• Zoning Ordinance title and purpose: § 1.10.010–§ 1.10.030 (Appendix I—Zoning)
• Code organization, combining-district priority: § 1.20.010(B)–(F)
• Zoning maps and compliance: § 1.20.060, § 1.20.070
• Rural slope-density and districts: § 2.20.040 (Table 2.20-4)
• Urban residential development standards: § 2.30.030 (Table 2.30-3)
• Commercial/industrial standards and supplemental rules: Table 2.40-2; § 2.40.040
• Special Purpose districts (A1, RS, OS/F, SCA): § 2.50.010; OS/F standards § 2.50.040
• Lot-size/setbacks combining districts: § 3.10.030
• Viewshed “-d1”: § 3.20.030–§ 3.20.040
• Scenic Roads “-sr”: § 3.30.030
• Historic Preservation “-h”: § 3.50.050–§ 3.50.070
• Housing Opportunity Sites “-os”: § 3.75.010–§ 3.75.020
• Review authority and common procedures: § 5.10.020; § 5.10.060; § 5.20.010–§ 5.20.030; § 5.20.070
• Architecture & Site Approval (ASA): § 5.40.010–§ 5.40.040
• Design Review: § 5.50.020–§ 5.50.040
• Parking: § 4.30.010–§ 4.30.020
• Nonconformities/public nuisance: § 4.50.090
• Building permit requirement: Sec. C1-67
• Hillside building site approval (≥30% slopes): § C12-350.1
• Official Plan Lines: Ch. C12-701–C12-703
• HCP/NCCP adoption: § C20-2