Campbell — Overlay Districts

Last reviewed: July 1, 2026

Overview

Overlay or combining districts in Campbell modify base zoning rules where site- or area-specific conditions need special attention. The overlay chapters in the Campbell Zoning Code explain how overlays are shown on the zoning map, how they are appended to base zones (suffixes), and the permit/eligibility buckets for different overlay types (for example Historic (H), Overlay (O), Community Benefit (CB), By-Right Housing (BRH), Reuse Sites (RS), and Affordable Housing (AH)). See the chapter-purpose and applicability rules in § 21.14.010 . This page summarizes what each Campbell overlay does, the most decision-relevant standards, and how they interact with the base zone and procedural chapters (e.g., development standards, parking, and design review).

Note: when this page mentions city processes and technical rules, it links to the relevant Campbell subjects (for quick navigation): Campbell Development Standards, Campbell Parking, Campbell Design Review, Campbell Historic Preservation, Campbell ADUs, and the California Building Standards Code.

How overlays are shown and applied

• Overlay districts are added as a suffix to the base zoning symbol (example: R-1-6-H, TO-MU-CB) and illustrated on the zoning map; the general rule and applicability are in § 21.14.010 and the map incorporation rule is § 21.04.030 .
• Overlays do not automatically eliminate base-zone requirements except where the overlay specifically adjusts lot area, lot width, open space, setbacks, height and parking requirements or when expressly stated by the overlay language (§ 21.14.030.A) .
• Verify the zoning map suffix on the official zoning map on file with the Community Development Department (zoning map adoption: § 21.04.030) .

Overlay districts — district-by-district breakdown

H — Historic Preservation (21.14.020)

• Purpose: Identify, protect, and preserve historic and cultural resources; applies consistent with Chapter 21.33 (Historic Preservation). See § 21.14.020 .
• Typical permitted uses: Principal, accessory and conditional uses remain those of the base zoning district; the overlay triggers historic-preservation review and rules in Chapter 21.33 (i.e., uses are not independently reclassified by the H overlay) (§ 21.14.020.D) .
• Key design/permit impacts: Projects within H are subject to historic-design processes and design guidance in Chapter 21.33; expect additional review for material changes and possible Mills Act considerations (definitions and requirements are in the Historic Preservation chapter) (§ 21.14.020.C) . Consult Campbell Historic Preservation and Campbell Design Review pages for procedure coordination.

Practical guidance: If your parcel carries an H suffix, plan for mandatory historic-resource review early (pre-application recommended) and factor possible extra conditions on exterior alterations.

O — Overlay (general commercial/industrial overlay) (21.14.030)

• Purpose: Provide modifications, additions or limits to commercial and industrial base zones to address special conditions; the O overlay may only be combined with identified commercial or industrial base zones (§ 21.14.030.A) .
• Permit requirement: A Conditional Use Permit (CUP) issued by City Council on recommendation from Planning Commission is required before establishing buildings/uses in a base zone combined with O; the CUP can also further restrict allowed uses beyond the base zone (§ 21.14.030.B) .
• Practical effects: The O overlay often modifies setbacks, heights, lot-area or parking requirements for the mapped area; always check the ordinance or the establishing master use permit for any site-specific standards (§ 21.14.030.A–C) .

Practical guidance: For commercial/industrial redevelopment in an O area, expect discretionary CUP review, potential master-use permit conditions, and site-specific controls on parking and loading that may override typical Development Standards — consult Campbell Parking and Campbell Development Standards.

CB — Community Benefit overlay (21.14.040)

• Purpose: An optional combining district allowing larger housing projects to deviate from Chapter 21.07 objective standards in exchange for demonstrable community benefits (e.g., deeper affordability, transportation improvements) (§ 21.14.040.A) .
• Eligibility and thresholds: Must propose development that yields 25 or more additional residential units, show a clear community benefit, and property owners must waive certain HAA rights as specified (§ 21.14.040.C.1–3) .
• Process: A pre-application is required (see Chapter 21.41) and the CB overlay is established by ordinance (the ordinance that creates the CB overlay must include any alternative objective standards for the site) (§ 21.14.040.B–D) .
• Permit/review outcomes: The CB overlay makes projects subject to a discretionary review track instead of the objective streamlined track; if the overlay ordinance does not define site-specific standards, the base zone standards apply by default (§ 21.14.040.E) .

Practical guidance: For large residential proposals considering CB, prepare a robust community-benefit package, expect discretionary hearings, and verify which objective standards (if any) are being traded off. See Campbell Design Review and Campbell Development Standards for related submittal expectations.

BRH — By‑Right Housing overlay (21.14.050)

• Purpose: Promote housing on sites identified to meet lower-income RHNA shortfalls by enabling by‑right development where certain criteria are met (§ 21.14.050.A) .
• Eligibility/standards:
  • Minimum density: must permit at least 30 units per acre for the site or portion of a site (§ 21.14.050.B.1) .
  • Minimum unit count: permit at least 16 units per site (§ 21.14.050.B.2) .
  • Use mix: Sites can be residential-only; for mixed-use projects at least 50% of gross floor area must be residential (§ 21.14.050.C.1–2) .
• Permit processing: Projects with ≥20% lower-income affordable units receive expedited ministerial processing under Chapter 21.39; the BRH overlay itself is created by ordinance (§ 21.14.050.D–E) .

Practical guidance: If your site is mapped BRH, confirm the exact ordinance that placed the overlay (it may specify site limits) and verify how the BRH interacts with the Multi‑Family Development and Design Standards and ministerial pathways. See Campbell Development Standards and the local ministerial approvals pages.

RS — Reuse Sites overlay (21.14.060)

• Purpose: Encourage housing on previously-identified Housing Opportunity Sites by allowing certain sites to be used for housing consistent with the Housing Element and General Plan (§ 21.14.060.A–B) .
• Eligibility: Applies to non‑vacant and vacant Housing Opportunity Sites as identified in current and prior Housing Elements (§ 21.14.060.B.1–2) .
• Processing: Projects with ≥20% lower‑income affordable units are eligible for expedited ministerial processing under Chapter 21.39; establishment of RS is by ordinance (§ 21.14.060.C–D) .

Practical guidance: If a property is in RS, confirm the parcel’s designation in the adopted zoning map and Housing Element, and coordinate with staff early about whether the project qualifies for ministerial processing.

AH — Affordable Housing overlay (21.14.070)

• Purpose: Promote affordable housing by providing incentives to projects that elect to comply with the AH overlay requirements; the AH overlay is intended to be voluntary and incentive-based (§ 21.14.070.A–B) .
• Permit processes and tiers: The AH overlay defines specific permit processing rules and may allow different permit tiers for projects that meet its objective requirements; some housing permits in the MFDDS still require Administrative, Minor, or Major permit categories depending on unit counts and overlay requirements (§ 21.14.070.D; cross-reference Chapter 21.07) .
• Practical limits: The overlay is established by ordinance and may contain site-specific standards and incentives; the exact incentives for AH sites are set in the ordinance establishing that overlay. For the code text about permit tiers and exceptions, see Chapter 21.07 and cross-references to the overlay § 21.14.070 .

Practical guidance: Because AH incentives are ordinance-specific, verify the overlay ordinance language for the parcel in question; not all AH overlays are identical—some expressly modify parking, density, or design standards.

Quick comparison table (decision‑relevant items)

How overlays interact with other standards and processes

• Overlays are additive to base-zone rules unless the overlay ordinance explicitly modifies a standard; see § 21.14.030.A for examples of the kinds of standards that may be varied (setbacks, height, parking, etc.) .
• Many housing overlays reference the Multi‑Family Development & Design Standards (MFDDS); see inclusion of the MFDDS/Form-Based Zoning Map in § 21.07.030 for how those standards apply to housing projects and how overlays may interact with permit tiers .
• If an overlay changes parking obligations, the parking rules still reference the city’s parking standards (consult Campbell Parking) and the overlay ordinance must be read to see if parking is reduced or altered; see § 21.14.030.A for the kinds of changes overlays can make .
• Historic overlays require coordination with Chapter 21.33 and the city's historic resource inventory—expect special design guidance and potential limitations on material changes to exteriors; see § 21.14.020 .
• Where overlays create alternative objective standards (especially for housing overlays like CB, BRH, AH, and RS), the ordinance creating the overlay must spell out those standards and the review track; if not, base-zone rules apply by default (§ 21.14.040.E) .

Checklist — what an applicant must satisfy (high level)

• Confirm the parcel’s base zone and any overlay suffix on the official zoning map (zoning map on file) per § 21.04.030 .
• Identify which overlay(s) apply (H, O, CB, BRH, RS, AH) and read the ordinance establishing that overlay (§ 21.14.010–070) .
• For H overlays: perform historic-resource review and follow Chapter 21.33 procedures and design guidelines (§ 21.14.020) .
• For O overlays: prepare for a Conditional Use Permit and review of any master-use permit conditions (§ 21.14.030) .
• For CB/BRH/AH/RS overlays: confirm eligibility thresholds (e.g., 25+ units for CB; 30 units/acre and ≥16 units for BRH; ≥20% lower-income for expedited paths) and prepare required affordability/community-benefit documentation (§ 21.14.040–070) .
• Coordinate early with staff (pre-application recommended for CB/large overlays) and confirm whether the project qualifies for ministerial or discretionary processing (see Chapter 21.07 and 21.39) (§ 21.14.040.B; § 21.07.030) .
• Determine how overlays change parking, setbacks, or height compared to the base zone and plan civil and architectural submittals accordingly (see Campbell Parking and Campbell Development Standards) (§ 21.14.030.A) .
• If proposing ADUs, confirm whether overlay provisions or the MFDDS affect ADU treatment (ADU rules are in Chapter 21.23; ADUs often remain consistent with residential densities) — consult Campbell ADUs and relevant overlay ordinance language (note: ADU exemptions are explicitly referenced in Chapter 21.07) (§ 21.07.020) .
• Verify building-safety compliance with the California Building Standards Code (Title 24) for any physical construction—overlay provisions do not replace building-code requirements (see California Building Standards Code) (Not an overlay provision; local zoning controls land use only).

Risks & Ambiguities

Plain‑English Summary

Campbell’s overlays are extra rules or tools attached to a parcel’s normal zoning. Some overlays (like H) add historic-preservation review, some (like O) impose a required Conditional Use Permit and site-specific conditions, and others (like CB, BRH, RS, AH) are housing-focused overlays that change permit paths, density expectations, or offer incentives — each overlay is created by ordinance and the specific ordinance controls the details (§ 21.14.010–070) .

Source References

• Campbell Zoning Code — Chapter on Overlay/Combining Districts: § 21.14.010–21.14.070 (purpose, H, O, CB, BRH, RS, AH)
• Zoning map adoption and interpretation: § 21.04.030 (zoning map on file with Community Development)
• Multi‑Family Development & Design Standards and Form‑Based Zoning Map reference (how overlays interact with housing standards): § 21.07.030
• Practical code references cited above are taken from the Campbell Zoning Code (Title 21 — Zoning). The city’s official zoning document and adopted overlay ordinances should be consulted for the parcel‑specific legal text (on file with Community Development).

Retrieved passages

• Campbell Zoning Code (§ 1) High relevance show source text
• Campbell Zoning Code (§ 1) High relevance show source text
• Campbell Zoning Code (Chapter 21.60) High relevance show source text
• Campbell Zoning Code (§ 1) High relevance show source text
• Campbell Zoning Code (§ 1) High relevance show source text
• Campbell Zoning Code (Section 21.14.070.D.2) Medium relevance show source text
• Campbell Zoning Code (Chapter 21.39) Medium relevance show source text
• Campbell Zoning Code (Chapter 21.25) Medium relevance show source text

Cited sections

• Campbell Zoning Code — Chapter on Overlay/Combining Districts: **§ 21.14.010–21.14.070** (purpose, **H**, **O**, **CB**, **BRH**, **RS**, **AH**) (Chapter on)
• Zoning map adoption and interpretation: **§ 21.04.030** (zoning map on file with Community Development) (§ 21.04.030)
• Multi‑Family Development & Design Standards and Form‑Based Zoning Map reference (how overlays interact with housing standards): **§ 21.07.030** (§ 21.07.030)
• Practical code references cited above are taken from the Campbell Zoning Code (Title 21 — Zoning). The city’s official zoning document and adopted overlay ordinances should be consulted for the parcel‑specific legal text (on file with Community Development). (Title 21)
• Campbell_ZoningCode.md

• Official Campbell code library