Contra Costa County Zoning, Planning & Building Codes

Last reviewed: July 6, 2026

Overview

In Contra Costa County, zoning, land use, and development rules for the unincorporated areas live in the County’s Zoning Ordinance, adopted as Title 8 Zoning. It applies only in unincorporated Contra Costa County; incorporated cities adopt their own codes. Start with the County’s zoning map and district chapters, then confirm baseline rules in the general regulations and any applicable combining/overlay districts. Countywide growth policy is also shaped by the voter-adopted 65/35 Land Preservation Plan and Urban Limit Line in Title 8.

Contra Costa County’s 65/35 standard limits urban development to no more than 35% of land, with at least 65% preserved for agriculture, open space, wetlands, parks and other non-urban uses; the Urban Limit Line implements this countywide policy in the unincorporated areas (§ 82-1.006; § 82-1.010).

How Contra Costa County’s code is organized

• Title 8 is the County’s zoning code for unincorporated areas; Divisions 82 and 84 apply to all private/public uses of land in the unincorporated territory (§ 82-2.004).
• Division 84 establishes zoning districts and where their regulations live (§ 84-2.004).
• Division 82 contains countywide general rules (e.g., setbacks along highways, height exceptions for chimneys/mechanical appurtenances), enforcement, and interpretation (§ 82-12.202; § 82-12.402; § 82-2.006; § 82-2.008).
• Divisions 86 and 88 address special regulated areas/uses (e.g., airports; special land uses like cemeteries) (§ 86-2.202; § 88-2.202).
• District-specific regulations are organized consistently by chapter with subsections for permitted uses, lots, building height, yards, and off-street parking (e.g., R-6 in §§ 84-4.202, 84-4.602–.606, 84-4.802, 84-4.1002–.1006).

For process, most discretionary approvals reference the County’s land use permit procedures in Chapter 26-2 and variance provisions in § 82-6 (see, e.g., § 84-68.2202; § 84-26.2002; § 84-92.1002).

Zoning district families

Contra Costa County uses a broad set of base districts in Division 84; the zoning map and districts are established in § 84-2.004. Highlights include:

• Residential (single-family):
  • R-6, R-7, R-10, R-12, R-15, R-20, R-40, R-65, R-100. Example standards: R-6 minimum lot 6,000 sf (§ 84-4.602), max height 2.5 stories/35 ft (§ 84-4.802), side yards 5 ft min; 15 ft aggregate (§ 84-4.1002), front setback 20 ft (§ 84-4.1004). Larger-lot districts scale up yard/lot standards (e.g., R-100 front 30 ft, side 30 ft each/60 ft aggregate) (§§ 84-20.1004, 84-20.1002).
• Residential (two-family/multifamily):
  • D-1 (two-family), M-17, M-29 multiple-family districts. The M-17 chapter establishes allowed uses and regulations (§ 84-28.202). Rezoning to M-29 can be paired with development plan review (§ 84-26.1808).
• Commercial/office:
  • N-B Neighborhood Business and R-B Retail Business districts; each relies on a development plan and district-specific yard/parking standards (e.g., R-B: no side yards; 10 ft setback from highway/road boundaries) (§§ 84-50.1602–.1606; 84-52.1002; 84-52.1004). O-1 Office includes use-specific parking and landscaped open-area requirements (§§ 84-44.1202; 84-44.1602).
• Industrial:
  • L-I Light Industrial and H-I Heavy Industrial are recognized (e.g., as eligible locations for kennels under land use permits) (§ 82-20.002).
• Agricultural/Open Space:
  • A-2, A-3, A-20, A-40, A-80 and F-R Forest Recreation are recognized for open space when applied consistent with the General Plan (§ 82-2.018). In A-80, minimum lot area is 80 acres (§ 84-84.404(2)).
• Special housing implementation:
  • HE-C Housing Element Consistency district enables parcels from the Housing Element sites inventory to develop at assigned densities; it lists allowed residential and mixed-use co-located uses with parcel-specific densities (§§ 84-92.202; 84-92.402).

Citywide development standards

Use the district chapter for the controlling numbers; the County also sets some general rules in Division 82. See Contra Costa County Development Standards.

• Heights
  • Most single-family districts cap height at 2.5 stories/35 ft (e.g., R-6 § 84-4.802). Height exceptions apply to appurtenances like chimneys, mechanicals, towers (§ 82-2.008).
• Yards and setbacks
  • Example single-family baselines: R-6 front 20 ft (§ 84-4.1004), rear 15 ft (§ 84-4.1006), side yards 5 ft min; 15 ft aggregate (§ 84-4.1002). Larger-lot districts increase side/front yards (e.g., R-10 side 10 ft each/20 ft aggregate, front same as R-6) (§§ 84-8.1002; 84-8.1004). Countywide highway setbacks also apply: 10 ft from public roads and 5 ft from state highways (§ 82-12.402).
• Lot area/width/depth
  • Standards scale by district (e.g., R-6: 6,000 sf lot, 60 ft width, 90 ft depth; R-12: 12,000 sf lot, 100 ft width, 100 ft depth) (§§ 84-4.602–.606; 84-10.602–.606). Small-lot occupancy rules and public-acquisition adjustments are in Chapter 82-10 (§§ 82-10.002(c); 82-10.004).
• Off-street parking
  • Parking requirements live in each district’s “Off-Street Parking” article (e.g., R-10 references R-6 standards at § 84-8.1202; O-1 requires 1 space per 200 sf of floor area, with a 5-space minimum per full-time doctor for medical/dental) (§ 84-8.1202; § 84-44.1202). The County allows parking reductions through Transportation Demand Management in Chapter 82-32 (§ 82-32.008).

Example snapshot (selected districts):

• The R-6 district sets a 20 ft front setback, 15 ft rear, 5 ft minimum side yards with 15 ft aggregate, and a 2.5 stories/35 ft height cap (§§ 84-4.1004; 84-4.1006; 84-4.1002; 84-4.802).
• The R-10 district keeps the 20 ft front and 15 ft rear but increases side yards to 10 ft each (20 ft aggregate) (§§ 84-8.1004; 84-8.1006; 84-8.1002).
• The R-100 district requires a 30 ft front yard and 30 ft minimum side yards (60 ft aggregate) (§§ 84-20.1004; 84-20.1002).

Specific plans & overlays

Contra Costa County implements area- and topic-specific controls through combining/overlay districts and special districts. See Contra Costa County Overlay Districts.

• Combining/overlay districts that add or supersede base-zone rules:
  • -B Design Control: Adds design controls; development/alteration requires Planning Director review and findings; decisions are appealable (§§ 84-70.004; 84-70.006).
  • -K Kensington: Tailored to the Kensington area, emphasizing views, light/solar access, privacy, and neighborhood compatibility; it supersedes underlying zoning where conflicts arise (§ 84-74.206).
  • -T Transitional: Applies in transitional areas to allow limited nonresidential uses by land use permit alongside residential, with overlay rules taking priority over underlying zoning, except minimum lot size (§§ 84-72.204; 84-72.406; 84-72.408).
  • -CE Cannabis Exclusion: Prohibits commercial cannabis activities, regardless of underlying district, in listed unincorporated communities (§ 84-86.212).
  • -SG Solar Energy Generation: For solar facilities within agricultural districts; overlay governs if conflicts arise (§ 84-88.204).
• Special regulating areas
  • Floodplain management requires a floodplain permit within Special Flood Hazard Areas before issuance of grading/building permits (§ 82-28.802).
  • Airport land use and hazard protections (Buchanan Field/others) are regulated in Division 86 (§ 86-2.202).
• Planned development
  • P-1 Planned Unit: Rezoning to P-1 is processed with a development plan; upon approval, the ordinance plan and conditions become part of Title 8 for the site (§§ 84-66.1002; 84-66.1004; 84-66.1006).

Building permits & review

• Ministerial building permits are issued when a project complies with the base district, any applicable overlays, and required development standards; floodplain permits may be required first in mapped flood hazard areas (§ 82-28.802). Also see the California Building Standards Code.
• Discretionary review typically occurs through:
  • Land use permits/variances (per Chapter 26-2 and § 82-6 as cross-referenced in district chapters, e.g., §§ 84-68.2202; 84-26.2002).
  • Development plan review in districts that require it (e.g., N-B and HE-C): the zoning administrator or planning agency holds a public hearing, makes findings of consistency/compatibility, and may impose conditions; certain HE-C projects meeting affordability/density criteria are approved ministerially (§§ 84-50.1602–.1606; 84-92.806(b)).
• Design review/site plan and elevations may be required in specific districts and overlays (e.g., -B Design Control, O-1 Office) (§§ 84-70.006; 84-44.2002). See Contra Costa County Design Review.

State housing law in Contra Costa County

See California housing laws for statewide rules that the County implements locally.

• Accessory dwelling units (ADUs/JADUs)
  • ADUs and JADUs are allowed uses in residential districts (e.g., R-6 permits ADUs/JADUs by right) (§ 84-4.402(7)). The County maintains an ADU permit application process with required submittals (§ 82-24.008). State law ensures each lot can accommodate at least one 800 sf ADU with 4 ft side/rear setbacks and sets ADU height limits keyed to context (Gov. Code § 66321); see California ADU law.
• SB 9 (Urban lot split and two-unit housing)
  • Implemented locally as “Urban Housing Development” (Chapter 88-36) on lots in R-6, R-7, R-10, R-12, R-15, R-20, R-40, R-65, R-100 or P-1 for single-family uses (§ 88-36.010). Key standards include up to two units; minimum lot size 1,200 sf; four-foot side/rear setbacks for new units; and one off-street space per unit unless near transit/car share (§ 88-36.012(c)–(f)).
• Housing Element sites (rezones)
  • Parcels zoned HE-C can develop at assigned densities with clear district standards (e.g., front 10 ft, side 5 ft, rear 15 ft; height and lot coverage vary by density category). Certain HE-C multifamily projects with ≥20% lower-income units are approved ministerially (§§ 84-92.604; 84-92.806(b)).

Information Gaps

• Countywide FAR standards by district: Not found in retrieved materials; verify with the jurisdiction.
• Countywide rent stabilization for unincorporated areas: Not found in retrieved materials; verify with the jurisdiction.
• A complete list of named specific plans/area plans referenced directly in Title 8: Not found in retrieved materials; verify with the jurisdiction.

Source References

• Title 8 Zoning applies to unincorporated areas; districts established; enforcement and general rules: § 82-2.004; § 84-2.004; § 82-2.006; § 82-2.008; § 82-12.202; § 82-12.402.
• 65/35 Land Preservation Plan & Urban Limit Line: § 82-1.006; § 82-1.010.
• Residential examples (R-6, R-10, R-12, R-100): §§ 84-4.602–.606; 84-4.802; 84-4.1002–.1006; 84-8.1002–.1006; 84-10.602–.606; 84-20.1002–.1006.
• Commercial/office examples (N-B, R-B, O-1): §§ 84-50.1602–.1606; 84-52.1002; 84-52.1004; 84-44.1202; 84-44.1602.
• Overlays and special areas: §§ 84-70.006; 84-74.206; 84-72.204; 84-72.406; 84-72.408; 84-86.212; 84-88.204; 82-28.802; 86-2.202.
• Housing implementation: §§ 84-92.202; 84-92.402; 84-92.604; 84-92.806(b); 88-36.010; 88-36.012; 84-4.402(7); 82-24.008; Government Code § 66321 (ADU).

Related topics on GoCodebook:

• Contra Costa County Zoning
• Contra Costa County Development Standards
• Contra Costa County Parking
• Contra Costa County Design Review
• Contra Costa County Overlay Districts
• California Building Standards Code
• California housing laws
• California ADU law