Yorba Linda — Nonconforming Uses

Last reviewed: July 3, 2026

Overview

This page explains how Yorba Linda's Zoning Code treats nonconforming uses, nonconforming structures, and nonconforming lots (the rules are codified mainly in Chapter 18.34 of the Zoning Code). It summarizes what can be continued, when nonconformities must be eliminated, what enlargements or restorations are allowed, and how time limits and notice work under the Code. For context on where these rules apply, see the City's zoning overview and the City's development standards for setbacks and lot rules. Yorba Linda zoning & planning overview

Key controlling sections: § 18.34.010 through § 18.34.110 (Chapter 18.34 — Nonconforming Uses and Structures) and the zoning district and development-standards tables at § 18.08.020, § 18.10.090, and Table 18.12-2.

Chapter highlights (plain-English, ordinance grounding)

• A use or building that was lawful when established but does not meet current rules is a nonconforming use / nonconforming structure; definitions are in § 18.04.150.
• Nonconforming uses/structures may be continued and maintained, but enlarging, moving, or otherwise increasing the nonconformity is generally prohibited except where the Code specifically allows it (§ 18.34.020 and § 18.34.030).
• Additions to a legal nonconforming structure are limited so they do not increase the discrepancy; an applicant may be permitted to encroach up to 50 percent of the existing encroachment length (with an administrative deviation up to an additional 20 percent in limited cases) — see § 18.34.030(C) and accompanying Figure for calculation rules.
• If a nonconforming structure or use is voluntarily razed or destroyed beyond 50 percent of its value, it generally cannot be restored as nonconforming; the restoration rules differ for commercial/industrial vs residential zones (§ 18.34.060).
• If a nonconforming use is discontinued for 180 days or more (with limited exception for dwelling units), it cannot be reestablished (§ 18.34.070).
• The ordinance sets elimination timeframes by type and zone in Table 18.34‑1 (e.g., certain nonconforming uses in R zones have 10–15 years depending on building type; in C‑G zones some nonconforming uses have 20 years) and references building-type definitions in the adopted Uniform Building Code for those timeframes (§ 18.34.040).
• Conversion of one nonconforming use to another nonconforming use requires a use permit and Planning Commission findings; see § 18.34.050.
• Lack of required off‑street parking by itself does not make a use nonconforming (§ 18.34.090) — see the City’s rules on parking for how parking interacts with permits.

District-by-district breakdown (where nonconforming rules matter)

The Code establishes specific zone names that determine both what is permitted and how nonconformities are treated; see § 18.08.020 for the official list. The nonconforming rules in Chapter 18.34 apply across these zones, with several zone-specific exceptions or timeframes described below.

Note: each subsection below gives the zone name as used in the Zoning Code (bolded), a short purpose, typical permitted uses (high-level), the most relevant development standards that determine whether something is nonconforming (front setbacks, lot size, height, coverage), and where the zone applies (official map). For the full permitted‑use master table and the site-specific maps, consult the City's official zoning map and Table 18.08‑1.

R-A (Residential Agricultural)

• Purpose: Very low density residential and agricultural uses.
• Typical uses: Single-family residences, agricultural uses, accessory structures.
• Key dimensional standards: Maximum density 1.0 unit/acre; minimum lot size 1 acre (see Table 18.10‑02). Nonconformance often arises from smaller historic lots or older farm structures.
• Where it applies: Outlying/estate parcels as mapped by the official zoning map.

RLD (Residential Low‑Density)

• Purpose: Low-density single‑family neighborhoods.
• Typical uses: Single‑family homes and accessory uses.
• Key standards: Maximum density 1.0 unit/acre; min lot size ~39,000 sq. ft. (Table 18.10‑02). Nonconforming small lots are defined as nonconforming lots in § 18.04.150.

R‑E (Residential Estate) and R‑S (Residential Suburban) (includes the RS example figure in Chapter 18.34)

• Purpose: Larger-lot suburban/residential living; R‑S (Residential Suburban) is commonly encountered in Yorba Linda.
• Typical uses: Single‑family residential, accessory structures.
• Key standards (example): R‑S shows minimum lot sizes and setbacks in Table 18.10‑02 and is used as the illustrative example for calculating permitted encroachment allowances in Figure 18.34‑1 (see § 18.34.030(C)). If your addition projects into an existing nonconforming setback, the 50 percent rule applies.

R‑U (Residential Urban)

• Purpose: Smaller single‑family lots than R‑S (higher density suburban).
• Typical uses and standards: See Table 18.10‑02 for min lot size ~7,500 sq. ft., typical front/side/rear setbacks and coverage rules; nonconforming lots are common in older urban areas.

R‑M, RM‑20, RM‑30 (Residential Multiple‑Family zones)

• Purpose: Multifamily apartments at graduated densities (R‑M up to 10 units/acre, RM‑20 up to 20 units/acre, RM‑30 up to 30 units/acre) — see Table 18.10‑02.
• Typical uses: Duplexes, apartments, townhomes.
• Nonconforming issues: Additions or conversions that increase density or reduce required open space are constrained by § 18.34.030 and Table 18.34‑1 timeframes; special setback rules for taller buildings in R‑M apply (see § 18.10.100(A)(1)).

C‑O (Commercial Office), C‑N (Commercial Neighborhood), C‑G (Commercial General)

• Purpose: Office and commercial service districts. Massage establishments for example are limited to C‑N and C‑G by conditional use permit (see § 18.20.992).
• Typical uses: Retail, offices, restaurants (varies by subzone).
• Key dimensional standards: Table 18.12‑2 sets front setbacks (25 ft. typical), side/rear setbacks (typically 5–10 ft.), lot coverage (35–60%), and building height (up to 35 ft. in many C zones). Nonconforming commercial uses have longer allowed amortization periods in Table 18.34‑1 (examples: 20 years in C‑G for certain building types).

M‑1 (Light Manufacturing)

• Purpose: Light industrial and manufacturing.
• Typical uses: Warehouses, light manufacturing; signage and outdoor storage are regulated and sometimes prohibited (see Chapter 18.24 for signs).
• Nonconforming industrial uses are handled under Chapter 18.34, with requirements to eliminate screening/performance nonconformities within a set timeframe (Table 18.34‑1, § 18.34.040 and § 18.34.100(D)).

Special-purpose / combining zones (selected)

• PD (Planned Development), PS (Public & Semipublic), PL (Presidential Library), OS / OSR (Open Space / Open Space Ranchettes), and combining overlays such as (H) Historic Combining Zone and (O) Oil Production Combining Zone are listed at § 18.08.020; where applicable, nonconforming rules of Chapter 18.34 still apply, but specific planned-development conditions or historic overlay requirements can alter how nonconformities are regulated — check the overlay/PD conditions.

Where to confirm: the official zoning map defines where each zone applies; interpretations (e.g., whether a particular use is permitted) are delegated to the Community Development Director and may be referred to the Planning Commission under § 18.08.060.

Key standards and quick reference table

Practical guidance / interpretation tips

• Start by confirming status: obtain zoning verification (what zone the parcel is in per § 18.08.030) and determine whether the use or structure pre‑dated the rule that now prohibits it (§ 18.34.020).
• To evaluate whether an addition is allowed to a nonconforming structure, measure the existing encroachment length and apply the 50 percent rule in § 18.34.030(C); if you need a slightly larger allowance, an administrative adjustment under Chapter 18.38 may be possible (see administrative adjustment allowance in § 18.34.030(C)(5) and § 18.38).
• If the nonconforming use is a commercial or industrial use destroyed by calamity, check § 18.34.060(A) for the ≤50% allowance and the one‑year restoration start deadline; for residential zones see § 18.34.060(B).
• If you plan to change a nonconforming use to another nonconforming use, be prepared to demonstrate to the Planning Commission that the new use will not have a greater adverse impact and that it falls within the exceptions enumerated in § 18.34.100.
• The City will send elimination notices under § 18.34.110; lack of notice does not create a right to continue the nonconforming use. Always verify dates and compute amortization periods from the effective date of the zoning change where applicable (§ 18.34.080).

Along the way you will need to reference the City's development standards for setback/lot/coverage rules (because nonconformance is measured against those standards), consult design review if an addition triggers design review, and review overlay districts or historic preservation rules if an overlay modifies allowed work. Also note state ADU law can affect how nonconforming zoning conditions are treated for ADU permits — see the City's ADU page and state ADU guidance. Yorba Linda ADUs California ADU law

Checklist

• Confirm parcel zone designation on official zoning map and permitted uses list (see § 18.08.030 and Table 18.08‑1).
• Establish whether the use/structure was lawful when established (definition: § 18.04.150).
• Determine which elimination timeframe from Table 18.34‑1 applies and compute required compliance date (§ 18.34.040).
• If proposing alterations/additions, confirm the 50% encroachment rule and whether an administrative adjustment under Chapter 18.38 is needed (§ 18.34.030(C) & § 18.38).
• If converting to another nonconforming use, prepare a use permit application addressing the Planning Commission findings in § 18.34.050.
• If structure was damaged, document cost estimates and consult § 18.34.060 and the Building Official's restoration valuation requirement.
• Check whether parking or other development‑standard variances will be required and reference the City’s parking and variances and exceptions processes.
• Expect elimination notices from the Community Development Director and note appeal rights (§ 18.34.110).

Risks & Ambiguities

Plain-English Summary

If your building or business in Yorba Linda was legal when it started but no longer meets today's zoning rules, you can usually keep it — but you cannot expand the nonconformity, you must repair rather than rebuild if it is more than half destroyed, you lose the right if the use stops for 180 days, and the City will require elimination within the timetable in Table 18.34‑1 unless a specific exception applies; start by confirming your parcel's zone and the precise Code subsection that applies to your situation.

Source References

• Yorba Linda Zoning Code — Chapter 18.34 (Nonconforming Uses and Structures), including § 18.34.010–§ 18.34.110.
• Yorba Linda Zoning Code — § 18.04.150 (Definitions of “Nonconforming building/lot/use”).
• Yorba Linda Zoning Code — § 18.34.040 and Table 18.34‑1 (Elimination timeframes).
• Yorba Linda Zoning Code — § 18.34.030(C) (50% encroachment allowance and Figure 18.34‑1).
• Yorba Linda Zoning Code — § 18.34.060 (Restoration after damage).
• Yorba Linda Zoning Code — zones designated § 18.08.020 and development standards (Table 18.10‑02 and Table 18.12‑2).
• Yorba Linda Zoning Code — § 18.34.070 (Discontinuation / 180‑day rule) and § 18.34.090 (parking not sole criterion).
• Nonconforming satellite antennas — § 18.20.930 (special provisions).
• City resources (informational) you will likely need: Yorba Linda Zoning, Yorba Linda Development Standards, Yorba Linda Parking, Yorba Linda ADUs — use these pages to find forms, maps and process descriptions.
• State ADU guidance summary (internal handbook file included for reference on ADUs and nonconforming zoning): 2025 California ADU handbook (see nonconforming zoning notes).

Retrieved passages

• Yorba Linda Zoning Code (§ 18.34.080.) High relevance show source text
• CBC § 3 (§ 3) High relevance show source text
• CBC § 3 (§ 3) High relevance show source text
• CBC § 3 (§ 3) High relevance show source text
• Yorba Linda Zoning Code (§ 3) High relevance show source text
• Yorba Linda Zoning Code (§ 3) High relevance show source text
• Yorba Linda Zoning Code (§ 3) High relevance show source text
• Yorba Linda Zoning Code (§ 3) High relevance show source text
• CBC § 3 (§ 3) High relevance show source text
• Yorba Linda Zoning Code (§ 66314) Medium relevance show source text
• CBC § 66321 (§ 66321) Medium relevance show source text
• CBC § 66314 (§ 66314) Medium relevance show source text
• Yorba Linda Zoning Code (§ 3) Medium relevance show source text
• Yorba Linda Zoning Code (§ 3) Medium relevance show source text
• Yorba Linda Zoning Code (Article 10) Medium relevance show source text

Cited sections

• Yorba Linda Zoning Code — Chapter **18.34** (Nonconforming Uses and Structures), including **§ 18.34.010**–**§ 18.34.110**. (§ 18.34.010)
• Yorba Linda Zoning Code — **§ 18.04.150** (Definitions of “Nonconforming building/lot/use”). (§ 18.04.150)
• Yorba Linda Zoning Code — **§ 18.34.040** and **Table 18.34‑1** (Elimination timeframes). (§ 18.34.040)
• Yorba Linda Zoning Code — **§ 18.34.030(C)** (50% encroachment allowance and Figure 18.34‑1). (§ 18.34.030)
• Yorba Linda Zoning Code — **§ 18.34.060** (Restoration after damage). (§ 18.34.060)
• Yorba Linda Zoning Code — zones designated **§ 18.08.020** and development standards (Table 18.10‑02 and Table 18.12‑2). (§ 18.08.020)
• Yorba Linda Zoning Code — **§ 18.34.070** (Discontinuation / 180‑day rule) and **§ 18.34.090** (parking not sole criterion). (§ 18.34.070)
• Nonconforming satellite antennas — **§ 18.20.930** (special provisions). (§ 18.20.930)
• City resources (informational) you will likely need: Yorba Linda Zoning, Yorba Linda Development Standards, Yorba Linda Parking, Yorba Linda ADUs — use these pages to find forms, maps and process descriptions.
• State ADU guidance summary (internal handbook file included for reference on ADUs and nonconforming zoning): 2025 California ADU handbook (see nonconforming zoning notes).
• YorbaLinda_ZoningCode.md
• 2025 California ADU handbook.md

• Official Yorba Linda code library