Glenn County — Development Standards

Last reviewed: July 3, 2026

Overview

This page summarizes the development standards (setbacks, height, lot coverage, minimum lot sizes and density) that apply in the unincorporated areas of Glenn County under the Glenn County zoning ordinance (Title 15 zoning chapters in the ordinance file provided). It focuses on what the code actually says for each local zoning district and how those standards affect project feasibility and site design. For how zoning interacts with building code and permit submittal, note that the California Building Standards Code (Title 24) governs building code compliance; this page does not repeat Title 24 requirements. For county-level rules and mapping see the Glenn County Zoning overview.

Important cross-topics: minimum setbacks and lot coverage drive how much building area you can place on a lot; many zones also require site plan review or other discretionary reviews (see design review). Parking requirements are set separately (see parking). Overlay districts and special standards may modify base-zone rules (see Overlay Districts).

The summaries below quote the controlling code section number for each requirement (using the § symbol) and cite the ordinance text extracted from the uploaded Glenn County zoning code.

District-by-district development-standards

Notes on format: each district subsection lists purpose, typical permitted uses, then key dimensional standards (minimum lot size/width, front/side/rear setbacks, maximum height, maximum lot coverage or densities) with the controlling code citation.

AE — Exclusive Agricultural Zone

• Purpose & uses: preserves agricultural land and allows intensive and extensive agricultural activities. See § 15.33.010 for purpose and permitted uses.
• Key dimensional standards:
  • Minimum parcel sizes (by combining zone): AE‑20 = 17 acres; AE‑40 = 36 acres; AE‑80 = 72 acres. § 15.33.020.
  • Maximum building height: Residential 35 ft; agricultural structures up to 50 ft (exceptions for silos/tanks if airport limits permit). § 15.33.060 (see also similar height rules in other ag zones). Not all AE sub‑sections list every yard — verify with parcel zoning.
• Where it applies: widely used for prime farm lands; consult county zoning map. Verify site‑specific sub‑zone (AE‑20/40/80) before arithmetic.

FA — Forest / Agricultural (15.32)

• Purpose & uses: low‑density residential and resource uses in forested or mountainous lands. § 15.32.010–.050.
• Key dimensional standards:
  • Minimum lot size: 144 acres in the FA zone. § 15.32.050.
  • Setbacks: Front 30 ft measured from existing county right‑of‑way edge; side 25 ft; rear 25 ft. § 15.32.080.
  • Max height: Residential 35 ft; agricultural 50 ft (exceptions similar to AE). § 15.32.060.

AT — Agricultural‑Transition (15.34)

• Purpose & uses: transition from agriculture to lower‑density rural residential/ag uses. § 15.34.010.
• Key dimensional standards:
  • Minimum lot area: varies; sample items include min lot 8.5 acres for certain AT designations; parcels must abut public street and meet width requirements. § 15.34.050.
  • Setbacks: Front 30 ft; side interior 15 ft; rear 20–25 ft depending on subzone and use. § 15.34.060–.070.
  • Height: Residential 35 ft; agricultural structures up to 50 ft (exceptions). § 15.34.070.

RE / RE‑NW — Rural Residential Estate (15.35 / 15.36)

• Purpose & uses: low‑density single‑family residential, hobby farms, buffer between agriculture and urban uses. § 15.35.010.
• Key dimensional standards:
  • Minimum parcel sizes (RE subzones): RE‑1 = 40,000 sq ft; RE‑2 = 1.7 acres; RE‑5 = 4.25 acres; RE‑10 = 8.5 acres. § 15.35.050.
  • Setbacks: Front 30 ft; interior side 15 ft; corner side 15 ft; rear 25 ft. § 15.35.060.
  • Height: Residential 35 ft; agricultural buildings 50 ft with exceptions. § 15.35.070.
  • RE‑NW (North Willows) has similar yard/height rules; see § 15.36.060–.070 for exact text.

R‑1 — Single Family Residential (15.37)

• Purpose & uses: low‑density single‑family neighborhoods with typical residential accessory uses. § 15.37.010–.030.
• Key dimensional standards:
  • Minimum lot configuration / frontage: zone is limited to unincorporated areas with sewer/water or service area; refer to § 15.37.020–.060 for site area rules. § 15.37.060.
  • Setbacks (minimum yards): Front 20 ft; interior side 5 ft; corner side 10 ft (street side); rear 25 ft; accessory rear 5 ft. § 15.37.070.
  • Max height: Principal structures 30 ft; accessory structures 15 ft. § 15.37.080.
  • Maximum lot coverage: 40% normally; 30% where slopes > 30%. § 15.37.110.
  • Where it applies: unincorporated communities with sewer/water service. See site plan and permit notes below. § 15.37.020.

R‑M — Multiple Residential (15.38)

• Purpose & uses: higher density residential (multifamily), designed where utilities are available. § 15.38.010–.030.
• Key dimensional standards:
  • Density and lot area: standards for minimum building site area and min/max density exist in this chapter; consult § 15.38.050–.070. (Example: maximum density references and site area are listed in the code.)
  • Setbacks: Front 20 ft; interior side 5 ft; corner side 10 ft (street side); rear 20 ft; accessory rear 5 ft. § 15.38.080.
  • Max height: Up to 55 ft for structures; accessory 15 ft (newer renumbered provisions reflect this). § 15.38.090.
  • Max lot coverage: 40% in R‑M. § 15.38.120.

MU‑R — Mixed‑Use Residential (15.381) (newer adoption)

• Purpose & uses: mixed residential and compatible commercial uses where utilities are available; intended to help meet housing element sites. § 15.381.010–.030.
• Key dimensional standards:
  • Minimum site area: 4,000 sq ft with public sewer/water (see § 15.381.050–.060).
  • Density: Minimum 14 units/acre; maximum 25 units/acre. § 15.381.080.
  • Setbacks: Front 15 ft; interior side 5 ft; corner side 10 ft (street side); rear 20 ft. § 15.381.080.
  • Max height: Up to 55 ft for structures; accessory 15 ft. § 15.381.090.
  • Max lot coverage: 60% in MU‑R. § 15.381.120.

LC — Local Commercial (15.39)

• Purpose & uses: small, localized retail and services that serve surrounding neighborhoods. § 15.39.010–.020.
• Key dimensional standards:
  • Minimum lot size: 8,000 sq ft (public water & sewer); 20,000/40,000 with combinations of well/septic. § 15.39.050.
  • Lot width: Interior 80 ft; corner 100 ft. § 15.39.060.
  • Max lot coverage: 40% for single story; 35% for multi‑story. § 15.39.080.
  • Setbacks / yards: Front 20 ft (or 45 ft from centerline); rear none or 10 ft if contiguous to residential; side none or 10 ft if adjacent to residential. § 15.39.090.
  • Max height: Two stories or 30 ft (whichever is less); accessory 20 ft. § 15.39.100.

CC, C, SC, HVC — Commercial Districts (15.40, 15.41, 15.42, 15.43)

• Purpose & uses:
  • CC (Community Commercial) centers for larger community retail/service uses. § 15.40.010.
  • C (Commercial) and SC (Service Commercial) and HVC (Highway & Visitor Commercial) each describe permitted commercial uses targeted to different functions (community vs highway/travelers vs bulky goods/service). See § 15.41.010, § 15.42.010, § 15.43.010.
• Key dimensional standards (examples — consult the exact commercial chapter for your parcel):
  • SC (Service Commercial): min lot sizes 12,500 / 20,000 / 40,000 sq ft depending on utilities; max lot coverage 75%; front yard 10 ft or 35 ft from roadway centerline; principal height 35 ft; accessory 20 ft. § 15.42.050–.100.
  • C (Commercial): front yard none except where adjacent to residential; where adjacent to R districts, residential setbacks apply; max height up to 75 ft unless CUP is required. § 15.41.060–.070.
  • HVC (Highway & Visitor Commercial): front 20 ft (or 45 ft from centerline), side 5 ft, rear 20 ft, height two stories or 30 ft. § 15.43.080–.100.

M — Industrial (15.44) and MP — Industrial Park (15.51)

• Purpose & uses: accommodate light to heavy industrial, warehousing and industrial park campus development. § 15.44.010, § 15.51.010.
• Key dimensional standards:
  • M zone sets site area/configuration and yard requirements per § 15.44.050–.070 (refer to the chapter for use lists and yard rules).
  • MP: maximum lot coverage 75%, minimum yards (front 20 ft; side 10 ft normally; rear 20 ft) and maximum height 20 ft normally for accessory, with incremental height increases tied to additional setbacks per § 15.51.100. § 15.51.080–.100.

FS — Foothill‑Scenic (15.47)

• Purpose & uses: manage development in foothill/scenic areas with larger setbacks and special siting. § 15.47.010.
• Key dimensional standards:
  • Setbacks: Front 30 ft (measured from right‑of‑way), side 25 ft, rear 25 ft. § 15.47.080.
  • Height: Residential 35 ft; agricultural/structural 50 ft (exceptions). § 15.47.060.

PDR — Planned Development Residential (15.48)

• Purpose & uses: flexible standards where a project proposes a specific plan of development; standards are negotiated in the PDR approvals but guided by § 15.48.010–.120. Design details, open space, phasing, and circulation are part of the PDR approval.

Quick reference table — most decision‑relevant numeric standards

If your parcel is in a different district than listed above, consult the exact zone chapter cited in the Source References below.

Note: Floor‑area ratio (FAR) is not used as a primary numeric standard in the excerpts retrieved; the code uses lot coverage, height, density, and minimum building site area instead. Not found in retrieved materials.

Practical guidance & interpretation

• Setbacks and lot coverage are applied in the unincorporated areas exactly as written in each zone chapter — check the zone chapter for exceptions where adjacent to residential zoning (many commercial zones reduce side/rear requirements when not adjacent to R districts). See, for example, § 15.39.090 for LC yards and § 15.42.090 for SC yards.
• Heights sometimes allow larger agricultural structures (silos, tanks) to exceed ordinary limits, but they must still meet airport hazard rules where applicable. See the repeated exception language at § 15.32.060, § 15.35.070, § 15.34.070.
• Many districts require site plan review prior to or concurrent with building permit application (examples: § 15.39.110, § 15.43.110). That is where compliance with setbacks, parking (see parking), landscaping (see Landscaping and Screening), and performance standards is checked.
• If your project is in a location subject to an overlay (floodplain, historic, airport, etc.), overlay standards may be more restrictive; consult the Overlay Districts page and the overlay code. Conflicts are resolved in favor of the more stringent rule per § 15.55.080.
• Accessory dwellings / second units: MU‑R specifically references second‑dwelling rules (see § 15.381.030 referencing Chapter 15.175 for a second dwelling). For state ADU law interactions, consult California ADU law and verify any local Chapter 15.175 rules not fully included in the retrieved excerpts.

Checklist

• Confirm the parcel’s base zoning and any overlays in the unincorporated area via the county zoning map. (Verify zone chapter number before calculations.)
• Pull the zone chapter and note the controlling numeric standards: minimum lot area, minimum lot width, front/side/rear yard, maximum height, maximum lot coverage, and any density limits. (See relevant § citations above.)
• Check whether the parcel lies inside an overlay that modifies site standards (floodplain, airport, historic).
• Prepare a site plan showing setbacks, building footprints, proposed heights and lot coverage, and proposed parking count per the parking requirements.
• Determine whether site plan review, administrative permit, or conditional use permit is required (see the zone chapter’s “Uses Permitted With A Conditional Use Permit” or “Site Plan Review” clauses).
• Confirm sewer/water/service availability if minimum lot sizes differ by utility provision (many districts list different minimum lot sizes based on water/sewer). See e.g., § 15.39.050.
• If proposing any non‑standard height or lot coverage, determine whether a variance or conditional use permit is necessary and consult Variances and Exceptions.

Risks & Ambiguities

Plain-English Summary

If your property is in unincorporated Glenn County, the zoning chapter for the zone your parcel is in (for example § 15.37 for R‑1, § 15.35 for RE, § 15.38 for R‑M, § 15.381 for MU‑R) tells you the minimum lot size, how far buildings must sit back from property lines, how tall buildings can be, and how much of the lot can be covered by buildings. Always check the exact zone chapter and any overlays before finalizing a site plan — the code clauses cited above are the legal standards you must meet.

Source References

• Glenn County Zoning chapters (excerpts used above):
  • RE — Rural Residential Estate: § 15.35.050–15.35.070 (lot sizes, yards, heights).
  • RE‑NW: § 15.36.050–15.36.070.
  • R‑1 — Single Family: § 15.37.060–15.37.110 (yards, height, lot coverage).
  • R‑M — Multiple Residential: § 15.38.050–15.38.120 (setbacks, height, coverage).
  • MU‑R — Mixed‑Use Residential: § 15.381.030–15.381.120 (uses, density, setbacks, height, coverage).
  • LC / SC / CC / C / HVC (commercial): § 15.39, § 15.42, § 15.40, § 15.41, § 15.43 — see each chapter for yard and lot coverage exceptions and site plan review requirements.
  • Industrial / MP: § 15.44, § 15.51 (industrial uses, lot coverage, yards, height).
  • FA, AE, FS (agricultural/foothill): § 15.32, § 15.33, § 15.47.
  • General conflict rule: § 15.55.080 (more restrictive rule prevails).
• Other code excerpts showing site plan review or procedural notes are included in the chapters cited above (see each zone’s “Site Plan Review” subsection; e.g., § 15.39.110, § 15.43.110).
• Where the code references other county chapters (for instance Chapter 15.175 for second dwellings/ADUs), the snippet appears in the MU‑R chapter; see § 15.381.030.

Retrieved passages

• Glenn County Zoning Code (§ 2) High relevance show source text
• Glenn County Zoning Code (§ 2) High relevance show source text
• CFC § 3 (§ 3) High relevance show source text
• CFC § 381.070 High relevance show source text
• Glenn County Zoning Code (§ 2) High relevance show source text
• CFC § 2 (§ 2) High relevance show source text
• CFC § 2 (§ 2) High relevance show source text
• Glenn County Zoning Code (§ 2) High relevance show source text
• CFC § 2 (§ 2) High relevance show source text
• Glenn County Zoning Code (§ 2) High relevance show source text
• CFC § 3 (§ 3) High relevance show source text
• Glenn County Zoning Code (Chapter 15.745) High relevance show source text
• CFC § 15 (§ 15) High relevance show source text

Cited sections

• Glenn County Zoning chapters (excerpts used above):
• **RE — Rural Residential Estate**: **§ 15.35.050–15.35.070** (lot sizes, yards, heights). (§ 15.35.050)
• **RE‑NW**: **§ 15.36.050–15.36.070**. (§ 15.36.050)
• **R‑1 — Single Family**: **§ 15.37.060–15.37.110** (yards, height, lot coverage). (§ 15.37.060)
• **R‑M — Multiple Residential**: **§ 15.38.050–15.38.120** (setbacks, height, coverage). (§ 15.38.050)
• **MU‑R — Mixed‑Use Residential**: **§ 15.381.030–15.381.120** (uses, density, setbacks, height, coverage). (§ 15.381.030)
• **LC / SC / CC / C / HVC** (commercial): **§ 15.39**, **§ 15.42**, **§ 15.40**, **§ 15.41**, **§ 15.43** — see each chapter for yard and lot coverage exceptions and site plan review requirements. (§ 15.39)
• **Industrial / MP**: **§ 15.44**, **§ 15.51** (industrial uses, lot coverage, yards, height). (§ 15.44)
• **FA, AE, FS** (agricultural/foothill): **§ 15.32**, **§ 15.33**, **§ 15.47**. (§ 15.32)
• General conflict rule: **§ 15.55.080** (more restrictive rule prevails). (§ 15.55.080)
• Other code excerpts showing site plan review or procedural notes are included in the chapters cited above (see each zone’s “Site Plan Review” subsection; e.g., **§ 15.39.110**, **§ 15.43.110**). (§ 15.39.110)
• Where the code references other county chapters (for instance **Chapter 15.175** for second dwellings/ADUs), the snippet appears in the MU‑R chapter; see **§ 15.381.030**. (Chapter 15.175)
• GlennCounty_ZoningCode.md