Local zoning · San Bernardino County

San Bernardino County — Overlay Districts

Overlay Districts under the San Bernardino County local zoning and planning code, with the controlling citations.

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Last reviewed: July 6, 2026

Overview

In unincorporated San Bernardino County, overlay districts are add-on rules that sit on top of base zoning to address hazards, resources, compatibility, and special contexts. Overlays are established in the County’s Development Code Title 8 and are mapped either as a suffix to the base zone or on separate Countywide maps, then applied through amendments to the Land Use Plan. When an overlay applies, you still follow your base zoning—but the overlay can impose extra limits, studies, and design conditions. See the County’s general zoning framework and maps on the San Bernardino County Zoning pages and the countywide context on the zoning & planning overview.

In unincorporated areas, you must meet both your base zone and any overlay requirements, and if they conflict, the more restrictive rule controls under § 82.01.030(d).

Key countywide overlay mechanics:

  • How overlays display on maps. Some overlays appear as suffixes to the base zone on the Land Use Plan, while most hazard/resource overlays are maintained as separate maps. The Sphere Standards (SS) overlay applies only within designated city/town spheres of influence in unincorporated areas.
  • Approvals still follow the base zone. Projects must obtain the same planning approvals the base zone requires, plus any extra overlay-specific submittals or studies.
  • Minor relief can be possible. The County can grant Minor Variances to overlay standards—generally up to 30%—when justified, per Table 85-5.

For how overlays interact with use permissions, see San Bernardino County Land Use, and for dimensional and site rules that still apply alongside overlays, see San Bernardino County Development Standards. Where overlays trigger reviews or conditions, they may intersect with San Bernardino County Design Review and with topic-specific standards like San Bernardino County Landscaping and Screening.

What overlays exist in unincorporated San Bernardino County?

Table 82-2 establishes these overlay districts and their chapter references: AA, AP, AR, AH, BR, CP, FS, FP, GH, HW, MR, NH, OS, PR, SC, and SS. Notes: AA/AP/SC show as suffixes; most others are on separate maps; SS applies only within designated spheres and only to unincorporated areas.

District-by-District Breakdown

Additional Agriculture (AA) Overlay

  • Purpose. Expands animal-keeping and related agricultural allowances in rural neighborhoods where ag and rural living mix.
  • Where it applies. Neighborhoods of rural single dwellings on large parcels with small-scale commercial agriculture.
  • Typical permitted uses. Animal keeping as a primary use (subject to public health laws).
  • Key dimensional standards. Table 82-22 sets densities and minimum areas, e.g., poultry (female): 1 acre with up to 99; horses: 1 per 10,000 sq. ft. on 1/2-acre parcels (higher densities allowed as parcel size increases); hogs limited to nine with specified area thresholds. See full density table in § 82.07.040.

Agricultural Preserve (AP) Overlay

  • Purpose. Identifies Williamson Act lands and limits uses to those compatible with commercial agriculture; may be subject to Land Conservation Contracts.
  • Where it applies. Only to AG, RC, RL, and FW districts mapped as Agricultural Preserves in the General Plan.
  • Typical permitted uses. Agricultural production, on-site farm stands, certain utilities, flood control, resource recovery systems with agricultural feedstocks, and limited owner/manager dwellings on qualifying parcels; other compatible uses per Government Code.
  • Key dimensional standards. Development follows the base zoning standards; AP governs use compatibility.

Airport Safety (AR) Overlay

  • Purpose. Ensures land use compatibility and safety near public airports/heliports.
  • Where it applies. AR1–AR4 review areas around public airports/heliports and military low-altitude corridors; AR2 aligns with 65 CNEL/Ldn noise contours; AR3/AR4 follow FAA Part 77 imaginary surfaces and military corridors.
  • Typical permitted uses. Uses consistent with the General Plan, the applicable Airport Land Use Plan, and AR standards; no permanent structures or uses are allowed within AR1 (runway protection/crash hazard zones).
  • Key dimensional/operational standards. Consistency with adopted Airport Comprehensive Land Use Plans is required; some properties must provide buyer/tenant notice and avigation easements. Board action is required if a project is inconsistent with an Airport Plan.

Alternate Housing (AH) Overlay

  • Purpose. Provides an alternative to standard single-family dwelling standards on large rural sites.
  • Where it applies. Rural areas with a base zone that allows single dwellings; minimum site of 40 acres.
  • Typical permitted uses. Single dwelling consistent with AH standards.
  • Key dimensional standards. Minimum 725 sq. ft. floor area and 14 ft. minimum floor width, plus referenced single-family construction standards.

Biotic Resources (BR) Overlay

  • Purpose. Implements policies to protect identified sensitive species and habitats.
  • Where it applies. Areas identified by County/State/Federal agencies as habitat for unique/rare/threatened/endangered species; overlay applies to policy areas on the Open Space Overlay.
  • Typical permitted uses. Base-zone uses may proceed if biological constraints and mitigation are addressed.
  • Key submittals/standards. A biotic resources report is required for new uses or >25% increase in disturbed area; mitigation must be incorporated into conditions of approval; qualified biologist credentials are specified.

Cultural Resources Preservation (CP) Overlay

  • Purpose. Identifies/preserves archaeological and historic resources.
  • Where it applies. Areas with known or likely resources listed in state/national inventories.
  • Typical permitted uses. Base-zone uses with resource protection measures integrated.
  • Key submittals/standards. A qualified professional report with data recovery/protection measures is required; recommended measures must be incorporated; Native American monitoring can be required in high-sensitivity areas or if resources are discovered.

Fire Safety (FS) Overlay

  • Purpose. Adds standards in areas prone to wildland fire to protect life and property.
  • Where it applies. Mapped by Cal Fire, U.S. Forest Service, and County Fire on General Plan hazard maps.
  • Typical permitted uses. Base-zone uses with FS standards; notice to Fire Authority is required for development and land divisions in FS areas.
  • Key dimensional/operational standards. The code refers to § 82.13.050 for general development standards; landscaping standards can be modified in FS areas; density transfer formulas in slopes within FS are referenced in planned development rules. Specific FS numeric standards not found in retrieved materials; verify with the jurisdiction.

Floodplain Safety (FP) Overlay

  • Purpose. Manages flood hazard areas to minimize losses and meet National Flood Insurance Program (NFIP) requirements.
  • Where it applies. FEMA Flood Insurance Study (May 8, 2024) and FIRMs adopted by reference; separate map maintained by Public Works.
  • Typical permitted uses. Base-zone uses that meet flood protection requirements.
  • Key dimensional/operational standards. Elevate lowest residential floor above BFE (varies by zone: AE/AH +1 ft; AO +1 ft above depth; A without BFEs +2 ft above grade; Shaded X +1 ft above pre-development grade); nonresidential must elevate or dry-floodproof; flood openings required; elevation certifications and inspections by Floodplain Administrator.

Geologic Hazard (GH) Overlay

  • Purpose. Requires investigation and mitigation of faults, unstable slopes, liquefaction, seiche, and adverse soils.
  • Where it applies. Near mapped Alquist-Priolo faults and County-identified geologic hazard areas, including unstable slopes or adverse soils.
  • Typical permitted uses. Base-zone uses with required geologic/geotechnical studies; some residential additions/accessory structures are exempt.
  • Key dimensional standards. Minimum construction setbacks from active faults: 50 ft for human-occupied structures; 150 ft for critical facilities; utilities/streets discouraged within those setback belts except perpendicular crossings.

Hazardous Waste (HW) Overlay

  • Purpose. Controls siting, buffers, and review for hazardous waste facilities.
  • Where it applies. Concurrently with a General Plan Amendment and CUP where a hazardous waste facility is proposed; typically in RC (disposal/incineration) or IR (treatment/recycling/storage/transfer), with incineration siting caveats.
  • Typical permitted/prohibited uses. Compatible industrial/service uses may be allowed; agriculture, all residential, and high-occupancy sensitive uses (e.g., schools, hospitals) are prohibited within the overlay.
  • Key approvals. GP Amendment, CUP, Fire Department Special Use Permit, and ministerial building/grading permits.

Mineral Resources (MR) Overlay

  • Purpose. Protects mineral deposits for current/future extraction and requires reclamation of mined lands.
  • Where it applies. Existing/likely mining areas and adjacent buffer areas.
  • Typical permitted uses. Mining and compatible uses; non-mining projects only if findings can minimize conflicts with mineral policies; Reclamation Plan required per SMARA.
  • Key standards. Incompatible uses are prohibited; reclamation is required when mining ceases; buffers and transitions must ensure compatibility.

Noise Hazard (NH) Overlay

  • Purpose. Protects residents and sensitive receptors from high ambient noise.
  • Where it applies. Areas with Ldn ≥ 65 dBA.
  • Typical permitted uses. Base-zone uses with noise mitigation; acoustical report required for residential projects.
  • Key standards. Interior noise ≤ 45 dBA Ldn (residential/educational); exterior noise should be ≤ 65 dBA Ldn and shall not exceed 70 dBA Ldn, with enforceable mitigation considered by the review authority.

Open Space (OS) Overlay

  • Purpose. Balances open space needs (natural resource, recreation, trails, and other open land uses) in an urbanizing County.
  • Where it applies. County-designated open space policy areas; interacts with habitat and trail networks.
  • Typical permitted uses. Open space and recreation consistent with the overlay’s policy framework. Not found in retrieved materials for a consolidated permitted-use table.
  • Key standards. The OS chapter provides trail standards/figures for multi-use corridors (e.g., minimum widths of 6–10 ft. for two-way bicycle/pedestrian segments per Table 82-24). Verify site-specific applicability under OS mapping. Not all implementing standards were retrieved.

Paleontologic Resources (PR) Overlay

  • Purpose. Identifies and preserves significant fossil resources and requires mitigation during grading where warranted.
  • Where it applies. Areas known or likely to contain paleontologic resources (per museum/locality files).
  • Typical permitted uses. Base-zone uses with resource evaluation and mitigation if fossiliferous units are present.
  • Key submittals/standards. Field surveys in potential areas; full-time monitoring in known fossil areas during grading; curation at the County Museum; mitigation cost caps defined for project types.

Sign Control (SC) Overlay

  • Purpose. Limits large freestanding signs where neighborhood character may be harmed.
  • Where it applies. Mapped where sign impacts are a concern; appears as a bracketed suffix (e.g., CG‑SC[150]).
  • Typical permitted uses. Base-zone uses, with stricter freestanding sign limits. For overall sign rules and permits, see San Bernardino County Signage.
  • Key standards. Max sign height 25 ft; max sign area equals the bracketed number; suffix “[p]” prohibits off-site freestanding signs >18 sq ft.

Sphere Standards (SS) Overlay

  • Purpose. Allows County to apply County or city-like development standards in specified city/town spheres of influence (still unincorporated land).
  • Where it applies. Only within listed spheres by adoption date/prefix; standards apply solely to the unincorporated portions of those spheres.
  • Typical permitted uses and standards. Defined by the SS chapter cross-references (Table 82‑23) and any adopted city-related standards incorporated by ordinance.

Quick-reference: Decision-critical overlay rules

Overlay What triggers it A few key standards you must meet Code Reference
Airport Safety (AR) Within AR1–AR4 near airports No permanent structures in AR1; consistency with Airport Land Use Plan; buyer/tenant notices and avigation easements may apply § 82.09.060; § 82.09.040; § 82.09.020; notifications at § 82.09 (g)
Floodplain Safety (FP) FEMA FIRM/FIS areas (5/8/2024) Elevate or dry-floodproof per zone; certify lowest floor; flood openings; inspections § 82.14.020; § 82.14.050(d); § 82.14.030; § 82.14.050(7)
Geologic Hazard (GH) Faults, unstable slopes, liquefaction, etc. 50 ft min. from active faults for occupied buildings; 150 ft for critical facilities; geologic/geotechnical reports § 82.15.040; § 82.15.030
Noise Hazard (NH) Ldn ≥ 65 dBA areas Acoustical report; interior ≤ 45 dBA Ldn; exterior ≤ 65 dBA Ldn (≤ 70 max with mitigation) § 82.18.020–.030
Alternate Housing (AH) Rural parcels ≥ 40 acres allowing single dwellings Min home 725 sq ft and 14 ft width; follow referenced dwelling standards § 82.10.020–.030
Hazardous Waste (HW) Proposed hazardous waste facility GP Amendment + CUP + Fire SUP; prohibits residential/ag uses within the overlay § 82.16.020–.030
Biotic Resources (BR) Identified habitat areas Biotic report for new or >25% added disturbance; integrate mitigation; qualified biologists § 82.11.030–.050
Sign Control (SC) Areas where large signs harm character Max 25 ft freestanding height; area per [bracket]; “[p]” = no large off-site signs § 82.21.020–.030

Checklist

  • Confirm whether your parcel is in any overlay (suffix on the Land Use Plan or separate hazard/resource map) through San Bernardino County Zoning and the county’s Land Use Plan maps.
  • Identify applicable base-zone approvals and remember overlays do not replace them (they add to them).
  • If in AR, check the applicable Airport Plan and AR1–AR4 area; confirm consistency and any required notices/avigation easements.
  • If in FP, obtain floodplain determinations, elevation/dry-floodproofing designs, flood openings, and required certifications/inspections.
  • If in GH, scope a geologic or geotechnical report; observe fault setback distances.
  • If in BR/CP/PR, retain qualified specialists and submit required resource reports/monitoring/curation plans; integrate mitigation into conditions.
  • If in FS, send required notices to the Fire Authority and confirm FS development standards; note FS may modify landscaping rules.
  • If in HW or MR, confirm required entitlements (e.g., GP amendment/CUP for HW) and reclamation/compatibility findings for MR.
  • If in AP, confirm Williamson Act compatibility; if in AA, confirm animal densities/lot area thresholds.
  • Consider whether a Minor Variance to overlay standards (up to ~30%) is appropriate; engage early with staff.
  • Coordinate early with County staff on any Design Review, Development Standards, and Landscaping and Screening items that overlays may affect.

Risks & Ambiguities

Issue Why it matters What to verify
Overlay mapping format Some overlays are suffixes; others are on separate County maps; SS applies only within certain spheres Confirm mapping type and latest map layer; if boundaries are unclear, the Director/Commission interpret boundaries under § 82.01.020(f)
Conflicting standards Overlays can be stricter than base zoning The most restrictive rule applies under § 82.01.030(d)
FEMA updates FP overlays adopt FEMA’s 5/8/2024 FIS/FIRMs and future revisions Check current FIRMs and any Letter of Map Changes; Public Works keeps the official copies
Airport consistency Different Airport Plans have different criteria Identify which Airport Plan applies and whether Board review is needed if inconsistent
FS standards detail § 82.13.050 is cited but not in retrieved excerpts Request FS standards from County; note FS can alter landscaping and density transfer calculations
AP compatible uses nuance Williamson Act compatibility controls uses and densities Confirm allowed “compatible uses” under § 82.08.040 and contract terms
MR non-mining uses Some non-mining projects can proceed only with specific findings Confirm ability to make MR findings and any SMARA obligations
Signage in SC areas Extra sign limits can affect project identity/visibility Confirm bracketed area and height limits and any “[p]” prohibition

Plain-English Summary

If you’re in an overlay in unincorporated San Bernardino County, you must do everything your base zoning requires—and more. Overlays can require extra studies (like biology, archaeology, paleontology, geology), higher construction elevations in flood zones, airport-related limits, or special sign caps. Start by confirming which overlay map applies, then plan for the added reports and conditions; if needed, the County can sometimes approve a Minor Variance to overlay standards.

Source References

  • Applicability to unincorporated areas: § 81.01.050
  • Overlays—purpose, mapping, applicability: § 82.01.030; Table 82‑2 (Overlays)
  • AA Additional Agriculture: §§ 82.07.010–.040 (incl. Table 82‑22)
  • AP Agricultural Preserve: §§ 82.08.010–.040
  • AR Airport Safety: §§ 82.09.010–.060 (incl. review areas and standards)
  • AH Alternate Housing: §§ 82.10.010–.030
  • BR Biotic Resources: §§ 82.11.010–.050
  • CP Cultural Resources Preservation: §§ 82.12.010–.050
  • FS Fire Safety: §§ 82.13.010–.040; see also § 83.10.040(c) (landscaping modification) and planned development references to § 82.13.050
  • FP Floodplain Safety: §§ 82.14.010–.030; § 82.14.050 (elevation, flood openings, etc.); § 82.14.070 (boundary changes)
  • GH Geologic Hazard: §§ 82.15.010–.040
  • HW Hazardous Waste: §§ 82.16.010–.030
  • MR Mineral Resources: §§ 82.17.010–.040
  • NH Noise Hazard: §§ 82.18.010–.030
  • OS Open Space: § 82.19.010; trail standards/figures (Table 82‑24, Figures 82‑1 to 82‑4)
  • PR Paleontologic Resources: §§ 82.20.010–.040
  • SC Sign Control: §§ 82.21.020–.030
  • SS Sphere Standards: §§ 82.22.010–.020 (Table 82‑23)
  • Minor Variances (overlay relief up to ~30%): § 85.17.040 (Table 85‑5)

Also see:

Sources

Retrieved passages

  • San Bernardino County Zoning Code (§ 82.16.020) Medium relevance
  • San Bernardino County Zoning Code (Chapter 82.01) Medium relevance
  • San Bernardino County Zoning Code (§ 82.01.030) Medium relevance
  • San Bernardino County Zoning Code (Title 44) Medium relevance
  • San Bernardino County Zoning Code (§ 82.15.040) Medium relevance
  • San Bernardino County Zoning Code (Chapter 85.06) Medium relevance
  • San Bernardino County Zoning Code (§ 82.12.030) Medium relevance
  • San Bernardino County Zoning Code (CHAPTER 82.10) Medium relevance
  • San Bernardino County Zoning Code (CHAPTER 82.15) High relevance
  • San Bernardino County Zoning Code (title of) High relevance
  • San Bernardino County Zoning Code (CHAPTER 82.07) High relevance
  • San Bernardino County Zoning Code (§ 82.15.040) Medium relevance
  • San Bernardino County Zoning Code (CHAPTER 82.01) Medium relevance
  • San Bernardino County Zoning Code (§ 82.14.050) Medium relevance
  • San Bernardino County Zoning Code (CHAPTER 82.18) High relevance
  • San Bernardino County Zoning Code (§ 82.09.010) High relevance
  • San Bernardino County Zoning Code (§ 82.17.020) High relevance
  • San Bernardino County Zoning Code (§ 82.12.050) High relevance
  • San Bernardino County Zoning Code (§ 51201) High relevance
  • San Bernardino County Zoning Code (§ 82.09.040) Medium relevance
  • CFC § 83.01.060 (§83.01.060) Medium relevance
  • San Bernardino County Zoning Code (§ 82.08.020) High relevance
  • San Bernardino County Zoning Code (CHAPTER 82.08) High relevance
  • San Bernardino County Zoning Code (Chapter 82.22.) Medium relevance
  • San Bernardino County Zoning Code (Chapter 83.08) Medium relevance
  • San Bernardino County Zoning Code (§ 82.21.020) Medium relevance
  • San Bernardino County Zoning Code (Chapter 86.12) Medium relevance

Cited sections

Frequently asked questions

How do I check if my unincorporated parcel is in an overlay?

Start with the Land Use Plan maps for suffix overlays (e.g., SC) and the County’s separate hazard/resource overlay maps. Table 82‑2 lists which overlays are suffixes vs. separate maps. For boundary ambiguities, the Director/Commission interpret per § 82.01.020(f).

What happens if overlay rules conflict with my base zoning?

You must meet both, and the most restrictive rule controls per § 82.01.030(d). Base-zone approval processes still apply to projects inside overlays.

Do floodplain rules require me to raise my house?

Often yes. In AE/AH zones the lowest floor must be at least 1 ft above BFE; in AO, 1 ft above mapped depth; in A without BFEs, 2 ft above natural grade; Shaded X, 1 ft above natural pre-development grade. Certification and flood openings are required.

I’m near an airport. What does the AR overlay mean?

Expect review for land use compatibility; no permanent buildings are allowed in AR1 (runway protection). Projects must be consistent with the applicable Airport Plan, and some sites require buyer/tenant notices and avigation easements.

Do I need a geologic report in the Geologic Hazard (GH) overlay?

If your project creates structures/roads or subdivides in GH areas, yes. Fault setbacks include 50 ft for occupied buildings and 150 ft for critical facilities; some small residential work is exempt.

I’m planning a subdivision within a Fire Safety (FS) overlay. Any special steps?

Yes. The County must notify the Fire Authority of your application; FS development standards apply countywide in mapped fire hazard areas, and FS can modify certain landscaping standards. Ask staff for the FS standards referenced in § 82.13.050.

Can I seek relief from an overlay standard?

Possibly. The County may grant a Minor Variance to overlay standards (generally up to 30%) if findings are met; major deviations require a Major Variance.

What is “compatible” in an Agricultural Preserve (AP) overlay?

Uses must support agriculture and comply with Williamson Act rules—e.g., production, certain support facilities, some limited dwellings for owners/managers on qualifying parcels. Check § 82.08.040 for the compatible use list.

Do overlays change my parking or general design rules?

Overlays add to—not replace—general development standards like parking and site design; you still follow countywide standards unless the overlay says otherwise. See Development Standards and Parking pages; for design review scopes, see Design Review.

Are signage rules different in the Sign Control (SC) overlay?

Yes. Freestanding signs are capped at 25 ft in height, area is limited by the bracketed suffix, and “p” suffixes prohibit large off-site freestanding signs.

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