Napa County — Zoning

Last reviewed: July 6, 2026

Overview

Napa County’s zoning rules live in Title 18 (Zoning) of the Napa County Code and apply only in the county’s unincorporated areas. The county divides land into named base districts and “combination” (overlay) districts, and it administers an official zoning map that is the final authority for zoning status. Start at the county’s zoning & planning overview, then use the official map and the Schedule of Zoning District Regulations referenced in the code to understand what is allowed on a given parcel (§ 18.12.010; § 18.12.020; § 18.12.070) .

The official zoning map maintained by the Planning Director is the final authority on zoning status in unincorporated Napa County; copies are not controlling (§ 18.12.020) .

How Napa County’s zoning is structured

• Base districts are established and listed by letter codes (e.g., AP, AW, RS, RM, CN, IP) in § 18.12.010, with development standards implemented through district chapters and the countywide Schedule of Zoning District Regulations in § 18.104.010 (referenced by § 18.12.070) .
• Combination zoning districts (overlays) modify or add to the base district rules (e.g., :AC Airport Compatibility, :AH Affordable Housing) (§ 18.08.160; § 18.12.010) .
• Map administration (adoption, identification, amendment, replacement) is spelled out in § 18.12.020–.050; amendments do not take effect until entered on the official map (§ 18.12.040) .

Base Zoning Districts (Unincorporated Areas)

Below are the principal districts in § 18.12.010, with purposes, common permitted directions, and where they typically apply. Dimensional numbers (setbacks, heights, lot sizes) are established by the district chapters and the Schedule of Zoning District Regulations in § 18.104.010 (not reproduced here) and by county Development Standards where applicable (§ 18.12.070) .

AP — Agricultural Preserve

• Purpose: Keep agriculture as the predominant use on valley and foothill lands; preclude incompatible urban uses (§ 18.16.010) .
• Typical permitted uses: Agriculture, one single-family dwelling per legal lot, small residential care, family day care (small/large, with criteria), and ADUs/JADUs subject to § 18.104.180 (§ 18.16.020) . Pre‑1974 wineries may continue within defined limits; expansion requires a use permit (§ 18.16.020(G))—see Nonconforming Uses for context .
• Key dimensional standards: See Schedule in § 18.104.010; road setbacks also apply (§ 18.112.010) .
• Where it applies: Fertile valley/foothill agricultural lands (§ 18.16.010) .

AW — Agricultural Watershed

• Purpose: Protect agriculturally oriented watershed areas, reservoirs, and floodplain tributaries (§ 18.20.010) .
• Typical permitted uses: Agriculture, one single-family dwelling per legal lot, ADUs/JADUs per § 18.104.180, small residential care, family day care (small/large with criteria), one guest cottage per § 18.104.080, certain telecommunications, and winery provisions mirroring AP (including rules for pre‑1974 wineries and small-winery exemptions) (§ 18.20.020) .
• Key dimensional standards: See Schedule in § 18.104.010; road setbacks also apply (§ 18.112.010) .
• Where it applies: Watershed/open space hillsides and reservoir tributary areas (§ 18.20.010) .

RS — Residential Single

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials. Use-permit uses include parks/recreation, residential care (medium/large), child day care centers, certain schools, and technical-need telecommunications (§ 18.52.030) .
• Special rule: “Deep lots” may allow a second dwelling by use permit with specific spacing, driveway, and density standards (§ 18.52.040); general RS standards refer to the county schedule (§ 18.52.050) .
• Where it applies: Verify with the jurisdiction.

RM — Residential Multiple

• Purpose: Provide for multi-family housing in areas otherwise suitable for RS, within established urban areas served by public roads and public water/sewer (§ 18.60.010) .
• Typical permitted uses: Multi-family dwellings (per district intent); supportive and transitional housing are treated as residential uses subject to RM standards (§ 18.60.020 J–K excerpt) . Use permits may allow parks/recreation, child day care centers, and certain telecommunications (§ 18.60.030) .
• Programmatic standards: Projects with multi-family or SRO units must provide 20% affordable units for lower‑income households (§ 18.60.040(A)) and follow ministerial review for the building permit phase; subdivisions follow Title 17 processes (land division) (§ 18.60.040(A))—see Land Use for context .
• Where it applies: Urbanized areas with full services (§ 18.60.010) .

RC — Residential Country

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials.
• Key dimensional standards: See § 18.104.010 (Not found in retrieved materials).
• Where it applies: Verify with the jurisdiction.

CN — Commercial Neighborhood

• Purpose: Not found in retrieved materials.
• Typical permitted uses: By right—agriculture, minor antennas, some telecom with site plan approval (§ 18.32.020). With a use permit—small-scale retail, food markets, services, gas stations, medical/dental offices, schools, and more; added allowances for Lake Berryessa/Capell Valley (e.g., small restaurants, auto supply, contractor storage) (§ 18.32.030) .
• Key dimensional standards: See § 18.104.010 (Not found in retrieved materials).
• Where it applies: Neighborhood nodes; additional CN options called out at Lake Berryessa and Capell Valley (§ 18.32.030(B)) .

CL — Commercial Limited

• Purpose/uses/dimensional standards: Not found in retrieved materials.
• Note: The code authorizes “commercial accessory dwelling units” on CL parcels per § 18.104.030 (with cross‑references to district use tables)—see California housing laws for state context .
• Where it applies: Verify with the jurisdiction.

MC — Marine Commercial

• Purpose/uses/dimensional standards: Not found in retrieved materials.
• Note: “Commercial accessory dwelling units” can also be authorized on MC parcels under § 18.104.030 (see above) .
• Where it applies: Verify with the jurisdiction.

I — Industrial; IP — Industrial Park; GI — General Industrial

• Purpose/uses/dimensional standards: Not found in retrieved materials. See Schedule in § 18.104.010; Parking and freight loading standards apply countywide to industrial uses (e.g., § 18.110.060–.070) .
• Where they apply: Verify with the jurisdiction.

PD — Planned Development

• Purpose/uses/dimensional standards: Not found in retrieved materials. Projects with development plans are governed by § 18.104.060 and must conform to approved development plans at the use-permit stage; revisions follow § 18.104.060(B) .
• Where it applies: Verify with the jurisdiction.

PL — Public Lands

• Purpose/uses/dimensional standards/where: Not found in retrieved materials.

AV — Airport

• Purpose/uses/dimensional standards: Not found in retrieved materials. Parcels near the Napa County Airport must also satisfy Airport Land Use Compatibility requirements in Chapter 18.80 (applies in addition to the principal district) (§ 18.80.040; § 18.80.080)—see Overlay Districts and Design Review for process interplay .

TP — Timber Preserve

• Purpose: Applied to portions of parcels to protect timber resources (intent set out in § 18.68.010) .
• Typical permitted uses, key standards, where: Not found in retrieved materials.

NP — Napa Pipe Principal Districts (NP-MUR-W, NP-IBP-W, NP-IBP)

• Purpose: Implement the Napa Pipe Project, allowing flexible, coordinated mixed-use and business park development with deviation from standard setbacks/coverage/height via district‑specific design guidelines and a development plan (§ 18.66.010; § 18.66.030) .
• Districts: NP‑MUR‑W (Mixed Use Residential—Waterfront), NP‑IBP‑W (Industrial/Business Park—Waterfront), NP‑IBP (Industrial/Business Park) (§ 18.66.020) .
• By-right examples (NP‑MUR‑W): small family day care, small residential care, home occupations, shelters meeting § 18.104.065, and minor antennas (§ 18.66.070) .
• Open space: At least 15% of total NP area must be publicly accessible common use/open space (§ 18.66.050) .
• Mobility/operations: Bicycle parking and freight loading reference county standards (§ 18.66.290–.300; Chapter 18.110) . NP signage combines district guidelines with county sign rules (§ 18.66.310)—see Signage .
• Process: NP development plans and design guidelines are approved using zoning‑amendment procedures (§ 18.66.320). Interim uses/time‑limited space are separately reviewed (§ 18.66.010(J)) .
• Where it applies: Parcels mapped “Napa Pipe” on the official zoning map (§ 18.66.010(A)) .

Combination/Overlay Districts (apply only in unincorporated areas)

• What they are: Combination districts expand or limit uses/standards of the underlying base zone (§ 18.08.160) .
• Established overlays include: :B Building Site, :AC Airport Compatibility, :HR Historic Restaurant, :UR Urban Reserve, :PS Agricultural Produce Stand, :SWP Skyline Wilderness Park, :AH Affordable Housing (§ 18.12.010)—see Overlay Districts .
• :AC Airport Compatibility: Projects within airport compatibility zones must meet the Countywide Airport Land Use Compatibility Plan; these requirements apply in addition to base-district rules (§ 18.80.040; § 18.80.080–.090) .
• :AH Affordable Housing: Establishes minimum/maximum densities and affordability on specified Housing Element sites; residential development on 2023 sites must achieve at least 20 units/acre and not exceed 25 units/acre, with affordability requirements and agreements per Chapter 18.107 (§ 18.82.010–.030) .

Countywide Rules That Intersect Zoning

• Zoning regulations are minimums and apply uniformly; no commercial use is allowed in unincorporated areas unless Title 18 authorizes it (§ 18.12.080(C)) .
• Development standards (setbacks, height, lot coverage) are organized in the Schedule of Zoning District Regulations (§ 18.104.010 referenced by § 18.12.070) and by subject chapters such as Parking and Landscaping and Screening (§ 18.12.070; § 18.110.060–.070) .
• Some commercial zones allow a limited “commercial accessory dwelling unit” on the same parcel as the principal commercial use (§ 18.104.030)—coordinate with California ADU law and the county’s ADU standards (§ 18.104.180, referenced in AP/AW) .
• Signage is controlled by both district rules and county sign chapters; NP has added signage parameters (§ 18.66.310)—see Signage .
• Projects often interact with Design Review and may require exceptions or variances; see Variances and Exceptions. For building standards, see the California Building Standards Code.

Permitted Uses Snapshot (selected districts)

Checklist

• Confirm the parcel is in the unincorporated area (incorporated cities have their own codes).
• Look up the base zoning district on the official map; treat the official map as final for zoning status (§ 18.12.020) .
• Identify any combination/overlay districts on the parcel (e.g., :AC, :AH) (§ 18.12.010; § 18.08.160) .
• Pull district-specific use lists and cross-check the Schedule of Zoning District Regulations (§ 18.104.010 referenced by § 18.12.070) .
• Check countywide standards that may apply: Parking and loading (e.g., § 18.110.060–.070), Signage, Landscaping and Screening .
• For NP (Napa Pipe) parcels, review the required development plan/design guidelines (§ 18.66.030; § 18.66.320) and open-space minimum (§ 18.66.050) .
• If near the airport, verify Airport Compatibility overlay requirements (§ 18.80.040; § 18.80.080–.090) .
• If proposing an ADU/JADU in AP or AW, confirm compliance with § 18.104.180 and state law; see California ADU law (AP § 18.16.020(F); AW § 18.20.020(C)) .
• For pre‑1974 winery rights in AP/AW, verify baseline entitlements and any needed use permits (AP § 18.16.020(G); AW § 18.20.020(H))—see Nonconforming Uses .
• Confirm whether Design Review or other discretionary approvals are triggered by your project scope.

Risks & Ambiguities

Information Gaps

• Dimensional standards (setbacks, heights, lot sizes, coverage) by district: Not found in retrieved materials. See § 18.104.010 (Schedule of Zoning District Regulations) referenced by § 18.12.070 .
• Purpose/use lists for CL, MC, I, IP, GI, PL, RC, AV, and detailed TP use lists: Not found in retrieved materials.
• RS by-right use list and district intent statement: Not found in retrieved materials.
• Some parking design standards and landscaping minimums in Chapter 18.110 (beyond the cited loading/improvement sections): Not fully visible in retrieved materials.

Plain-English Summary

If your property is in unincorporated Napa County, your allowable uses and building envelope are set by a base zoning district (like AP or RS), any combination overlays (like :AC near the airport), the official zoning map, and countywide standards. Start by confirming your zoning on the official map, then check the district’s use list and the Schedule of Zoning District Regulations; if you’re in the Napa Pipe area, you must also follow its development plan and design guidelines.

Source References

• Napa County Code Title 18—Zoning: Establishment of districts, official map, and application of regulations (§ 18.12.010; § 18.12.020–.050; § 18.12.070–.080)
• AP Agricultural Preserve district intent and uses (§ 18.16.010; § 18.16.020)
• AW Agricultural Watershed district intent and uses (§ 18.20.010; § 18.20.020)
• RS Residential Single use-permit list, deep-lot rules, general applicability (§ 18.52.030–.050)
• RM Residential Multiple intent, uses, and affordability program (§ 18.60.010; § 18.60.020(J)-(K); § 18.60.030; § 18.60.040(A))
• CN Commercial Neighborhood uses (§ 18.32.020–.030)
• Combination zoning districts (§ 18.08.160; § 18.12.010)
• Airport Compatibility overlay applicability and review (§ 18.80.040; § 18.80.080–.090)
• :AH Affordable Housing overlay densities/affordability (§ 18.82.010–.030)
• NP Napa Pipe districts: intent, establishment, plan/guidelines, uses, open space, signage, and approvals (§ 18.66.010–.070; § 18.66.050; § 18.66.290–.320)
• Parking/loading and improvements (selected) (Chapter 18.110; § 18.110.060–.070)
• Road Setbacks (§ 18.112.010)

Retrieved passages

• Napa County Zoning Code (§ 2) High relevance show source text
• Napa County Zoning Code (§ 1) High relevance show source text
• Napa County Zoning Code (Chapter 18.12) High relevance show source text
• Napa County Zoning Code (§ 14) High relevance show source text
• Napa County Zoning Code (Chapter 18.66) Medium relevance show source text
• Napa County Zoning Code (§ 2) Medium relevance show source text
• Napa County Zoning Code (Section 18.104.170.) Medium relevance show source text
• Napa County Zoning Code (§ 3) Medium relevance show source text

Cited sections

• Napa County Code Title 18—Zoning: Establishment of districts, official map, and application of regulations (§ 18.12.010; § 18.12.020–.050; § 18.12.070–.080) (Title 18)
• AP Agricultural Preserve district intent and uses (§ 18.16.010; § 18.16.020) (§ 18.16.010)
• AW Agricultural Watershed district intent and uses (§ 18.20.010; § 18.20.020) (§ 18.20.010)
• RS Residential Single use-permit list, deep-lot rules, general applicability (§ 18.52.030–.050) (§ 18.52.030)
• RM Residential Multiple intent, uses, and affordability program (§ 18.60.010; § 18.60.020(J)-(K); § 18.60.030; § 18.60.040(A)) (§ 18.60.010)
• CN Commercial Neighborhood uses (§ 18.32.020–.030) (§ 18.32.020)
• Combination zoning districts (§ 18.08.160; § 18.12.010) (§ 18.08.160)
• Airport Compatibility overlay applicability and review (§ 18.80.040; § 18.80.080–.090) (§ 18.80.040)
• :AH Affordable Housing overlay densities/affordability (§ 18.82.010–.030) (§ 18.82.010)
• NP Napa Pipe districts: intent, establishment, plan/guidelines, uses, open space, signage, and approvals (§ 18.66.010–.070; § 18.66.050; § 18.66.290–.320) (§ 18.66.010)
• Parking/loading and improvements (selected) (Chapter 18.110; § 18.110.060–.070) (Chapter 18.110)
• Road Setbacks (§ 18.112.010) (§ 18.112.010)
• NapaCounty_ZoningCode.md

• Official Napa County code library