Tehama County — Nonconforming Uses

Last reviewed: July 6, 2026

Overview

In unincorporated areas of Tehama County, the rules for existing uses that no longer match today’s zoning are set in Title 17 (Zoning), Chapter 17.74 — Nonconforming Uses. These standards explain when a nonconforming use may continue, when it must be brought into compliance, and what happens if it is altered, abandoned, or destroyed. Related provisions in Chapter 17.08 (general development standards), Chapter 17.72 (variances), and select use-specific chapters round out how nonconformities are treated across the County’s zoning districts. All regulations in Title 17 apply only to the County’s unincorporated areas; incorporated cities within Tehama County have their own codes.

Most important: A nonconforming use can continue, but if it’s abandoned for six months or more it loses protection; if destroyed beyond one‑half its value, it generally must be rebuilt to current zoning standards (with a one‑year reconstruction window for dwellings). See § 17.74.010 and § 17.74.040.

Key concepts and scope

• Title 17 applies countywide in the County’s unincorporated areas.
• “Nonconforming use” and “nonconforming building” are defined in the County’s definitions chapter (Title 17, Chapter 17.04).
• The County’s general plan consistency policy acknowledges that some preexisting, inconsistent uses exist and explains why the nonconforming regulations are comparatively “relaxed.”

Core nonconforming rules that apply in any zoning district

The standards below apply regardless of the base zoning district in unincorporated Tehama County.

How other County provisions interact with nonconformities

• Setback flexibility for legal nonconformities: If a structure or property is determined “legally nonconforming” under § 17.74.010, the Planning Director may approve a setback adjustment to allow an addition that would otherwise encroach into an established setback line. See § 17.08.030(B).
• Variances and nonconforming rules: A variance may be granted where strict application of area/height/coverage/space standards or the regulations “pertaining to nonconforming uses” would cause practical difficulties or unnecessary hardships. See § 17.72.010 (and related procedures in § 17.72.020–.060). For process guidance, see Tehama County Variances and Exceptions.
• Nonconforming parcels and lot line adjustments: The County may approve a lot line adjustment even where parcels are nonconforming, subject to limits (e.g., a redescribed pre‑existing nonconforming parcel must be at least 80% of its original area, among other requirements). See § 17.75.020.
• Use‑specific amortization examples:
  • Mobile food vending units that were nonconforming had a limited six‑month amortization to come into compliance or be removed/relocated or obtain a use permit. See § 17.82.060.
  • Nonconforming occupied recreational vehicles or travel trailers may continue only if fully compliant as of the effective date; they cannot be transferred or structurally altered and must be brought into conformity by removal or relocation. See § 17.86.140.
• Policy grounding: Title 17 recognizes some preexisting uses are inconsistent with the general plan and notes the nonconforming regulations have been “relaxed” to balance plan consistency with practical considerations. See § 17.02.050(C).
• Enforcement backdrop: Buildings or uses contrary to Title 17 are unlawful and may be abated as public nuisances; each day is a separate offense. See § 17.78.020–.030.

Related topics you may need while evaluating a nonconforming site: Tehama County Zoning, Tehama County Development Standards, Tehama County Design Review, Tehama County Overlay Districts, Tehama County Parking, and Tehama County Signage.

District notes for nonconforming situations (selected)

Nonconforming rules above apply countywide, but the “target” standards you compare against differ by district. Below are selected districts commonly referenced when advising on nonconformities; always confirm parcel zoning on the Tehama County zoning & planning overview and cross‑check Tehama County Land Use.

AG-1 — Agricultural/Upland

• Purpose and place: Recognizes upland grazing lands; accommodates intensive and extensive agriculturally compatible uses; also allows compatible non‑agricultural uses (e.g., commercial recreation, resource protection/management, habitat management). Applies where the General Plan designates Upland Agriculture. See § 17.10.010(A).
• Dimensional framework: AG‑1 applies the general standards of Chapter 17.08 countywide in AG‑1 districts. See § 17.10.010(B).
• Nonconforming tip: If a pre‑code agricultural operation in AG‑1 ceases for ≥ six months, restarting it requires full compliance with today’s AG‑1 standards. See § 17.74.010.

AG-2 — Agricultural/Valley (selected standards shown)

• Where it applies: Valley agriculture (chapter not fully retrieved).
• Key dimensional standards: Minimum front yard is the greater of 50 ft from roadway centerline or 20 ft from property line; minimum side yards 10 ft (or 6 ft on legally nonconforming parcels ≤10 acres); minimum rear yard 20 ft; height generally 35 ft (with listed exceptions); minimum parking for dwellings is 1 space per unit. See § 17.11.040–.070.
• Nonconforming tip: Additions to a legally nonconforming AG‑2 home may be eligible for a setback adjustment per § 17.08.030(B) if the Director determines legal nonconforming status.

AG-3 — Agricultural/Small‑Farm

• Purpose and place: Includes lands for small‑farm and hobby‑farm production, limited animal keeping, and agricultural‑supporting uses, with non‑ag uses limited to protect rural character (El Camino and surrounding areas specifically noted). See § 17.12.010(A) (purpose text appears within Chapter 17.12).
• Typical permitted uses: Primary crop production; secondary livestock grazing/animal husbandry; certain semi‑heavy agricultural uses on parcels ≥20 acres; one rural residential dwelling per preexisting legal parcel (subject to other Title 17 limits); home occupations; specified agritourism/agricultural homestay uses meeting Chapter 17.81 standards. See § 17.12.020.
• Nonconforming tip: If a nonconforming commercial activity sits idle for six months, it cannot resume unless it conforms to AG‑3 allowances or secures appropriate approvals. See § 17.74.010.

M-1 — Light Industrial

• Typical permitted uses: Assembly, wholesale distribution/warehousing, crop production, accessory offices, personal services, data centers, minor manufacturing, etc.; certain auto/body shops and similar uses when enclosed; accessory living quarters; some uses require a conditional use permit (e.g., restaurants, vehicle sales). See § 17.34.020–.030.
• Key dimensional standards: Front yard 20 ft; no side or rear yards unless required by building/fire codes. See § 17.34.040.
• Nonconforming tip: If a nonconforming M‑1 use building is destroyed more than 50% of its value, any rebuilding must meet current M‑1 standards (no automatic right to reconstruct the old nonconforming use). See § 17.74.040.

Note: Specific commercial districts where mobile food vending may be permitted by use permit include C‑1, C‑2, C‑3, C‑4, as well as M‑1, M‑2, and P‑O, throughout unincorporated areas, illustrating how use permissions vary by district context. See § 17.82.030(D).

State‑level constraint that can affect “nonconforming” homeowner projects

If you are adding an ADU to a property with existing zoning nonconformities, State ADU law limits the County’s ability to deny an ADU solely due to existing “nonconforming zoning conditions,” unless there is a health and safety threat affected by the ADU work. See the State guidance summarized in the 2025 HCD handbook. For background, see California ADU law and California housing laws.

Checklist

• Confirm the use or structure was lawful when established (proof of legality) and is in unincorporated Tehama County.
• Determine whether the use has been abandoned/discontinued for six months or more. If so, plan for full compliance with current zoning.
• If proposing a use change without structural alteration, verify it is to a same or more restricted nonconforming classification.
• For any work on a nonconforming building, check the 50% in five years maintenance cap and consider whether a conversion to a permitted use is needed.
• If the building was destroyed beyond half its value, assess one‑year dwelling reconstruction rights and verify valuation by the County Building Official.
• If the structure is legally nonconforming but you need a minor setback relief for an addition, consult the Director about a setback adjustment under § 17.08.030(B).
• For nonconforming parcels, evaluate lot line adjustment options (e.g., 80% area rule) and other criteria in § 17.75.020.
• Consider a variance if strict application of nonconformity rules creates hardship, using the process in Chapter 17.72.
• If a use is subject to a special amortization (e.g., mobile food vending or RV/travel trailer occupancy), check the chapter‑specific requirements.

Risks & Ambiguities

Plain-English Summary

If your existing use or building in unincorporated Tehama County doesn’t match today’s zoning, you can usually keep it as‑is. But if you stop using it for six months, try to expand or alter it, or it’s heavily damaged, you’ll likely have to meet current rules—except a home can be rebuilt within one year after major damage. When in doubt, talk to Planning about setback adjustments or a variance, and confirm parcel and overlay constraints before you invest.

Source References

• Title 17 (Zoning) — Applicability, General Plan consistency and nonconforming policy: § 17.02.050(C); § 17.02.060.
• Definitions (including “nonconforming use/building”): Chapter 17.04 — Definitions.
• Nonconforming Uses (core rules): § 17.74.010–.050.
• Yards and nonconforming setback adjustments: § 17.08.030(B).
• Variances (including relief from nonconforming regulations): § 17.72.010–.060.
• Nonconforming parcels and lot line adjustments: § 17.75.020.
• Mobile food vending amortization and districts for permits: § 17.82.060; § 17.82.030(D).
• RV/travel trailer nonconforming amortization: § 17.86.140.
• Enforcement and remedies: § 17.78.020–.030.
• Selected district standards: AG‑1 (§ 17.10.010); AG‑2 (§ 17.11.040–.070); AG‑3 (§ 17.12.010–.030); M‑1 (§ 17.34.020–.050).
• State ADU law interplay (nonconforming conditions): HCD 2025 ADU Handbook (summary).

Retrieved passages

• Tehama County Zoning Code (Section 17.70.030.) High relevance show source text
• Tehama County Zoning Code (§2) High relevance show source text
• Tehama County Zoning Code (§2) Medium relevance show source text
• CBC § 18214 (section 18214.) Medium relevance show source text
• Tehama County Zoning Code (§2) Medium relevance show source text
• CBC § 66314 (§ 66314) Medium relevance show source text
• Tehama County Zoning Code (§ 66314) Medium relevance show source text
• Tehama County Zoning Code (§ 66333) Medium relevance show source text
• Tehama County Zoning Code (§ 1) Medium relevance show source text
• Tehama County Zoning Code (§ 1) Medium relevance show source text
• CBC § 18214 (section 18214.) Medium relevance show source text
• Tehama County Zoning Code (chapter shall) Medium relevance show source text

Cited sections

• Title 17 (Zoning) — Applicability, General Plan consistency and nonconforming policy: **§ 17.02.050(C)**; **§ 17.02.060**. (Title 17)
• Definitions (including “nonconforming use/building”): Chapter 17.04 — Definitions. (Chapter 17.04)
• Nonconforming Uses (core rules): **§ 17.74.010–.050**. (§ 17.74.010)
• Yards and nonconforming setback adjustments: **§ 17.08.030(B)**. (§ 17.08.030)
• Variances (including relief from nonconforming regulations): **§ 17.72.010–.060**. (§ 17.72.010)
• Nonconforming parcels and lot line adjustments: **§ 17.75.020**. (§ 17.75.020)
• Mobile food vending amortization and districts for permits: **§ 17.82.060**; **§ 17.82.030(D)**. (§ 17.82.060)
• RV/travel trailer nonconforming amortization: **§ 17.86.140**. (§ 17.86.140)
• Enforcement and remedies: **§ 17.78.020–.030**. (§ 17.78.020)
• Selected district standards: **AG‑1 (§ 17.10.010)**; **AG‑2 (§ 17.11.040–.070)**; **AG‑3 (§ 17.12.010–.030)**; **M‑1 (§ 17.34.020–.050)**. (§ 17.10.010)
• State ADU law interplay (nonconforming conditions): HCD 2025 ADU Handbook (summary).
• TehamaCounty_ZoningCode.md
• 2025 California ADU handbook.md

• Official Tehama County code library