Glenn County Zoning, Planning & Building Codes

Last reviewed: July 3, 2026

Overview

This page orients you to zoning, planning, and development regulation that applies in the unincorporated areas of Glenn County. The county’s land-use rules are codified in the Unified Development Code (Title 15) and are administered by the county planning authority; they apply only to unincorporated territory (not incorporated cities). The UDC organizes zones, development standards, performance rules, special districts/overlays, and permit procedures in a single title so you can trace a project from zoning district rules to site plan review and building permits. Key local rules: district lists and maps (§ 15.30.010–15.30.020), development standards and performance rules (Division 15‑4), and site-plan / discretionary permit procedures (§ 15.13 and § 15.04). § 15.01.010 § 15.30.010

(Quick links you’ll see referenced below: the county’s zoning overview is at Glenn County Zoning; look up countywide standards at Glenn County Development Standards; for site-layout rules see Glenn County Parking; design review basics are at Glenn County Design Review; overlays are under Glenn County Overlay Districts; and state rules that affect construction and ADUs are at California Building Standards Code and California ADU law.)

How Glenn County’s code is organized

• Title and scope — The zoning/UDC is titled the “Unified Development Code of Glenn County” and is codified as Title 15 of the county code; it applies to unincorporated areas (§ 15.01.010, § 15.01.030). § 15.01.010
• Divisions — The UDC is arranged into divisions: Division 15‑1 (General Provisions), Division 15‑2 (Development Permits), Division 15‑3 (Development Districts / zones), Division 15‑4 (Development Standards), and Division 15‑5 (Special Use Standards). This table-of-contents structure makes it straight‑forward to jump to (a) the zone rules that control uses and setbacks, (b) the development standards (parking, signs, landscaping), and (c) permit procedures. (See the UDC index list.) § 15.01 et seq.
• Maps and interpretation — The official zone map(s) and any special zone maps are maintained by the planning authority; the map rules and interpretation are in § 15.30.020 and land‑use interpretation rules live in § 15.03.020–15.03.040. § 15.30.020 § 15.03.020–15.03.040
• Decision authorities and hearings — Ministerial reviews (e.g., many site plan reviews) are handled by the Director; discretionary permits (use permits, variances, rezonings, some conditional uses) go to the Planning Commission or Board of Supervisors as required. Public hearing and notice procedures are in § 15.04. § 15.13.040 § 15.04.010–15.04.020

Zoning district families (what districts exist and where to look)

The UDC explicitly lists the county’s base and special districts; the county uses these zone names in the zone map and each zone has its own chapter of numeric standards. The base list includes agricultural/resource zones, residential types, commercial/industrial classes, planned districts, and overlay/special districts. For the complete list see § 15.30.010. § 15.30.010

Notable Glenn County districts (names are bolded as they appear in the code) with the UDC chapter to read next:

• AE (Exclusive Agricultural) — combining minimum parcel sizes AE‑20, AE‑40, AE‑80 are set out in § 15.33.020. § 15.33.020
• FA (Foothill Agricultural/Forestry) — minimum lot area, yards, and heights (e.g., 30 ft front yard; 25 ft side and rear) are in § 15.32.080–15.32.060. § 15.32.080 § 15.32.060
• R‑1 (Single‑family Residential), R‑M (Multiple Residential) and MU‑R (Mixed‑Use Residential) — multi‑family placement, density and minimum yard rules are in the R‑M and MU‑R chapters (see § 15.38 and § 15.381). The MU‑R chapter was added/renumbered recently to address sewer/water-served infill and Housing Element sites. § 15.38.010 § 15.381.010 file
• LC, C, CC, SC, HVC (Local, Commercial, Community, Service, Highway/Visitor Commercial) — commercial districts have distinct lot sizes, yards and height caps; for example HVC sets 50% lot coverage and front yard minima such as 20 ft or 45 ft from centerline depending on the road (§ 15.43.080–15.43.090). § 15.43.080 § 15.43.090
• M, MP (Industrial; Industrial Park) — industrial uses and performance requirements are in § 15.44 and § 15.51. § 15.44.010 § 15.51.010
• Planned and special districts: PDR, PDC (Planned Development Residential/Commercial), PDR/PDC require a general plan of development and a conditional use permit for specific plans (§ 15.48, § 15.49). § 15.48.030 § 15.49 (index)
• Other special resource/overlay districts: TPZ (Timberland Preserve), AP (Agricultural Preserve), FS (Farmland Security), FP (Floodplain), AV/AVH (Airport/Airport Hazard) — each has tailored standards (e.g., floodplain construction standards in § 15.54; airport hazard rules in § 15.55). § 15.54.010 § 15.55.080 file

If you need to find a zone on the map, the code requires the county to maintain zone maps under § 15.30.020. § 15.30.020

Citywide development standards (how setbacks, heights, coverage, parking and design controls work)

• How to find the standards — Countywide development standards and performance rules are grouped in Division 15‑4. That includes landscaping (§ 15.57), performance standards (noise, air, glare) (§ 15.56), density bonus (§ 15.60), off‑street parking and loading (§ 15.61), and sign standards (§ 15.62). See the division index and the specific chapter for numeric standards. § 15.56–15.62
• Typical dimensional examples — many districts repeat the pattern: the code lists minimum front/side/rear yards, maximum heights, and maximum lot coverage in each district chapter. Examples: FA front yard 30 ft, side/rear 25 ft, residential height 35 ft (§ 15.32.080–15.32.060); HVC lot coverage 50%, front yard 20 ft or 45 ft from centerline, max height 30 ft (§ 15.43.080–15.43.100). § 15.32.080 § 15.32.060 § 15.43.080 § 15.43.100
• Lot coverage and densities — each zone sets lot coverage or density caps (examples: many residential/RC zones list 35–75% coverage or explicit density minimums in their chapters; see the applicable zone chapter such as § 15.38 or § 15.381). § 15.38.120 § 15.381.120 file
• Parking — off‑street parking and loading rules are in the county’s parking chapter (§ 15.61). For most projects you’ll show required spaces on the site plan submitted for review; the director can require studies where necessary. See § 15.61 and the Performance Standards chapter for more (e.g., parking and circulation requirements for agricultural processing § 15.74.010). § 15.61 § 15.74.010 file (Also see Glenn County Parking.)
• Design and discretionary review — the code requires site plan review for most development and makes the Director the initial approving authority for site plan review (§ 15.13.040); site plan review findings are listed in § 15.13.050. Conditional Use Permits, variances and rezonings are discretionary and involve the Planning Commission and public hearings per § 15.04. § 15.13.040 § 15.13.050 § 15.04.010 filefile (See county design-review guidance at Glenn County Design Review.)
• Performance requirements — noise, air, waste, light/glare and other nuisance controls are in § 15.56 and apply to all uses unless explicitly exempted; specific standards (tabled sound limits, dust/erosion controls, setback rules for livestock) are present in that division and in special-use chapters. § 15.56.010–15.56.100
• Landscaping, walls and fences — landscaping standards are in § 15.57 and most commercial/industrial and conditional uses require screening, fences or walls (examples: six‑foot fences where an industrial/commercial use abuts residential, chapter references in multiple zone chapters). § 15.57 § 15.44.080 file

(For site‑specific numeric requirements always consult the individual zone chapter for that parcel — e.g., § 15.32 for FA, § 15.33 for AE, § 15.38 for R‑M, § 15.43 for HVC.) § 15.32 § 15.33 § 15.38 § 15.43 filefilefile

Specific plans, planned districts & overlays

• Planned districts — PDR and PDC (Planned Development Residential / Commercial) require rezoning accompanied by a general plan of development and generally require a conditional use permit for the specific plan before ministerial permits (grading, building, health) are issued for the project (§ 15.48.030). § 15.48.030
• Recreation / motorsport planned zone — the RPM district requires parcel minimums, a general plan of development, and conditional-use permit review for the specific plan (§ 15.52). § 15.52.020–15.52.060
• Overlays and special zones — Floodplain management (FP, § 15.54) and Airport Hazard (AVH, § 15.55) overlay chapters supply additional design and permit standards that “stack” on the base zone; where a conflict exists the more stringent rule applies (§ 15.55.080). § 15.54.010 § 15.55.080 file (See Glenn County Overlay Districts.)

Building permits & review — the typical path

1. Pre‑application / zoning check — for large or complex rezonings (PDR, RPM, PDC) the code anticipates preapplication meetings and submission of a general plan of development (§ 15.52.060). § 15.52.060
2. Site plan review / ministerial clearance — most building permits require a site plan submittal reviewed by the Director; the Director approves or conditions site plan review permits per the findings in § 15.13.050. Many district chapters reiterate the requirement that a site plan be submitted prior to or concurrent with a building permit application. § 15.13.030–15.13.060 § 15.32.090 file
3. Discretionary approvals where required — conditional use permits, variances, rezonings and environmental review follow the noticed/hearing procedures in § 15.04; appeals are handled under the appeals chapter (§ 15.05). § 15.04.010 § 15.05 (index) file
4. Building code & inspections — construction must comply with the California Building Standards (Title 24) and local building inspection references (the UDC repeatedly references the Uniform Building and Fire Codes in dimensional and spacing rules). When the UDC references building/fire standards it expects compliance with state codes enforced by the Building Department. § 15.32.070 (See California Building Standards Code.)
5. Conditions and bonding — the planning authority can require conditions, dedications, and public improvement performance in exchange for discretionary approvals; completion of required improvements is governed by the UDC improvement and completion rules. § 15.01.070 (improvements) and various discretionary chapters

State housing law in Glenn County — how it interacts with the UDC

• State controls that commonly affect county approvals — statewide ADU/JADU rules, SB 9 lot‑split/duplex provisions, density‑bonus law, and other state housing statutes can preempt or constrain local standards. Glenn County’s UDC includes a density bonus chapter at § 15.60 and an off‑street parking chapter at § 15.61 that must be interpreted consistent with state law. § 15.60 § 15.61
• ADUs — a local ADU chapter was not located in the retrieved UDC materials. State ADU law requires local agencies to allow ADUs under specified constraints (e.g., size, setbacks, parking exceptions). For state ADU rules see the California ADU guidance (uploaded file). Because I did not find a specific Glenn County ADU chapter in the retrieved materials, verify ADU implementation and any county ADU checklist with the County Planning/Building Department. Not found in retrieved materials; see state ADU law for required baseline standards.
• SB 9 / lot splits / ministerial housing approvals — the UDC contains ministerial and site plan provisions (§ 15.13) and a zoning‑map amendment/residential zoning structure (§ 15.30). Whether SB 9 lot splits or ministerial approvals apply on a particular parcel depends on (a) the parcel’s zone, (b) specific local standards, and (c) any local objective zoning provisions. Consult the planning director for an SB 9 ministerial determination; the code’s land‑use interpretation rules describe how to treat unlisted or similar uses (§ 15.03.020). § 15.13.030 § 15.30.010 § 15.03.020 filefile
• Density bonus — Glenn County has a local density bonus chapter (§ 15.60) that will be applied together with state density bonus law; read § 15.60 and consult planning staff for project‑level calculations. § 15.60

If you are developing housing, request a pre‑application meeting with county planning staff — the code explicitly anticipates preapplication review for planned development rezonings and other major projects (§ 15.52.060) and the director may require technical reports to demonstrate compliance with performance and public‑safety standards (§ 15.56.020). § 15.52.060 § 15.56.020 file

Information gaps / what to verify with the county

• I did not find a discrete Glenn County ADU ordinance chapter in the retrieved UDC materials; verify if the county has a separate ADU policy or local implementing procedures beyond state law (Not found in retrieved materials; confirm with Planning/Building).
• For parcel‑level numeric standards (exact setback in a particular R‑1 parcel, or whether a specific lot is in an overlay such as FP/AVH), check the official zone map maintained by the planning authority (§ 15.30.020) and the specific zone chapter for that parcel. § 15.30.020

Source References

• Glenn County Unified Development Code (Title 15) — UDC index and general provisions, Title of the code: § 15.01.010
• Zoning map and zone list: § 15.30.010–15.30.020 (zone list and zone maps)
• Site plan review and permit procedures: § 15.13.030–15.13.060 (site plan review; findings)
• Public hearings and notice: § 15.04.010–15.04.020 (hearing purpose & notice)
• Performance standards (noise, air, erosion): § 15.56 (division index and specifics)
• Off‑street parking, density bonus, signage: § 15.61, § 15.60, § 15.62 (Division 15‑4 index)
• Examples of district chapters: § 15.32 (FA — Foothill Ag/Forestry), § 15.33 (AE — Exclusive Ag), § 15.38 (R‑M), § 15.43 (HVC) — for dimensional standards and uses filefilefile
• Planned development / specific plan rules: § 15.48 (PDR) and § 15.52 (RPM) — general plan of development and conditional use permit requirements file
• Floodplain and airport hazard overlays: § 15.54, § 15.55 (special/combining districts) file
• County/State housing reference (state ADU guidance included in uploaded materials) — uploaded ADU handbook (state law summary)