Imperial — Nonconforming Uses

Last reviewed: July 6, 2026

Overview

This page explains how the City of Imperial regulates nonconforming uses, structures, and lots under its Zoning Ordinance. It focuses on what happens when an existing use or building no longer matches current zoning rules, including when such uses can continue, when they must be phased out, and what happens after damage or vacancy. For general background on districts and processes, see the Imperial zoning overview and the core framework under Imperial Zoning.

The most important rule: if a nonconforming use stops for 180 consecutive days, it loses its protected status and cannot be restarted unless the Planning Director approved a written schedule to resume before the lapse (§ 24.17.140; ).

How Imperial treats nonconformities

• Definitions
  • A nonconforming use was lawful when established but no longer conforms to the ordinance. A nonconforming building/structure lawfully existed but no longer meets current development standards. A nonconforming lot does not meet current lot area/frontage/dimension standards (§ 24.01.180; ).
• Continuation and maintenance
  • Lawfully established nonconforming uses and nonconforming structures may continue and be maintained, subject to the limits below (§ 24.17.120; ).
• Alterations and expansions
  • You cannot alter or reconstruct a nonconforming structure in a way that increases the nonconformity; relocation or enlargement must conform to current property development standards (§ 24.17.130.A; ).
  • A structure with a nonconforming use cannot be moved, altered or enlarged unless it eliminates the nonconformity or is required by law (§ 24.17.130.B; ).
  • A nonconforming use may be enlarged only within its existing building and without structural changes except those required by law (§ 24.17.130.C; ).
  • Special residential relief in the Town Core: an existing conforming residential use that is nonconforming only on side/rear setbacks may be enlarged with a variance, but only if the home is within the defined Town Core boundary and other findings are met; accessory structures and secondary dwelling units may not be enlarged under this relief (§ 24.17.130.E; ). For process, see Imperial Variances and Exceptions.
• Discontinuation (abandonment)
  • If a nonconforming use is discontinued or changed to a conforming use for 180 days or more, it cannot be re-established unless the Planning Director was notified in writing and approved a schedule to resume the use (§ 24.17.140; ).
• Restoration after damage
  • If a nonconforming structure/use is destroyed up to 50%, it may be restored and the nonconforming use resumed if work starts within one year and is diligently completed. If damage exceeds 50%, or the structure is voluntarily or legally razed, restoration must fully conform and the nonconforming use may not resume (§ 24.17.150.A–B; ). The 50% threshold is based on cost to restore vs. cost to replace, as reviewed by the Building Official using minimum cost under the building code (§ 24.17.150.B; ). See related dimensional rules on Imperial Development Standards.
• Elimination (amortization)
  • Imperial requires certain nonconforming uses and structures to be phased out within set timeframes after official notice (§ 24.17.160; ). Key deadlines are summarized in the table below.
• Change to another nonconforming use
  • A Use Permit may allow conversion from one nonconforming use to another only if impacts are not greater and the new use would be one allowed to continue per the elimination schedule (§ 24.17.170; ). See Imperial Design Review for related review triggers.
• When a use or structure becomes nonconforming
  • If a zone boundary or regulation changes, amortization clocks start on the effective date of the change (§ 24.17.190; ).
• Notice mechanics
  • Elimination periods begin upon certified-mail notice from the Planning Director; notices are also recorded and repeated annually (§ 24.17.195; ).

Key decision rules and timelines

District-by-district context for nonconforming uses

The elimination timelines and exceptions hinge on which district a use is in and whether it would be allowed today. For current allowances, cross-check the applicable district regulations under Imperial Land Use and Imperial Development Standards.

R zones (residential categories)

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials. Verify with the jurisdiction and § 24.03.110 (referenced but text not retrieved) for R-zone allowances (Not found in retrieved materials; ).
• Key dimensional standards: Not found in retrieved materials.
• Nonconforming rules that matter here:
  • A nonresidential use in an R zone that is not permitted/conditional in C1 must cease or conform within 15 years of notice (§ 24.17.160.A.2; ).
  • If that nonresidential use is permitted/conditional in C1, it may continue; a CUP can allow up to 10% expansion in any 5-year period, subject to the 180-day discontinuation and 50% damage rules (§ 24.17.160.A.2; ).
  • Existing nonconforming residential uses need not be removed, but cannot enlarge floor area or increase unit count; restoration after damage follows § 24.17.150 (§ 24.17.160.A, “Any zone, exception”; ).

C1 (commercial)

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials. Verify with § 24.05.120 (referenced but text not retrieved) (Not found in retrieved materials; ).
• Key dimensional standards: Not found in retrieved materials.
• Nonconforming rules that matter here:
  • C1 is the benchmark for determining whether certain nonresidential uses in R zones may continue and modestly expand under a CUP (§ 24.17.160.A.2; ).

C2 (commercial)

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials. Verify with § 24.05.120 (referenced but text not retrieved) (Not found in retrieved materials; ).
• Key dimensional standards: Not found in retrieved materials.
• Nonconforming rules that matter here:
  • Uses in C2 that are not permitted/conditional in any commercial or industrial district must cease or conform within 15 years (§ 24.17.160.A.3; ).
  • If the use is permitted/conditional in any commercial or any industrial district, it may continue; a CUP may allow up to 10% expansion in any 5-year period (§ 24.17.160.A.3, exception; ).

I zones (industrial)

• Purpose: Not found in retrieved materials.
• Typical permitted uses: Not found in retrieved materials. Verify with § 24.07.120 (referenced but text not retrieved) (Not found in retrieved materials; ).
• Key dimensional standards: Not found in retrieved materials.
• Nonconforming rules that matter here:
  • Uses not permitted/conditional in a commercial or industrial zone must conform or cease within 15 years after notice (§ 24.17.160.A.4; ).

SP — Specific Plan Zone

• Purpose: Implements a unified, plan-led zoning framework; details are set by an adopted Development Plan (§ 24.09.320–.330; ).
• Typical permitted uses: Established by the SP Development Plan; existing uses at the time the SP is created are deemed allowable and incorporated into the plan unless a termination schedule says otherwise (§ 24.09.320.B; ).
• Key dimensional standards: Set by the SP plan; by default there may be no minimum yards/open space, and a maximum of 35 ft/2 stories within 50 ft of the SP boundary unless the plan sets otherwise (§ 24.09.330.A.4; ).
• Nonconforming rules that matter here:
  • The SP can “normalize” existing uses by incorporating them into the plan text, changing how nonconformity would otherwise apply (§ 24.09.320.B; ). Coordinate early with Imperial Overlay Districts if an SP or overlay governs your site.

Tip: Whether an expansion or change triggers review will often dovetail with Imperial Parking, Imperial Design Review, and base-district development standards. For accessory or secondary dwelling-unit questions mentioned in the Town Core provision, see Imperial ADUs.

Checklist

• Confirm the existing use/structure was lawful when established (§ 24.17.120; ).
• Identify your district and whether today’s code would permit/conditionally permit your use (R, C1, C2, I, or SP) (Referenced: §§ 24.03.110, 24.05.120, 24.07.120; Not found in retrieved materials; ).
• Determine if any official notice of nonconformity has been recorded/mailed; note the compliance date (§ 24.17.195; ).
• Check vacancy history; if the use paused ≥180 days without an approved resumption schedule, protection may have lapsed (§ 24.17.140; ).
• If damaged, document cost-to-restore vs. cost-to-replace and confirm the Building Official’s 50% determination (§ 24.17.150.B; ).
• If seeking expansion or change: confirm limits (e.g., “inside the building only” for nonconforming uses; “no increased nonconformity” for structures) (§ 24.17.130; ).
• For R-zone nonresidential or C2-zone uses, assess eligibility for CUP-based 10% expansions and ensure consistency with discontinuation/damage rules (§ 24.17.160; ).
• If in Town Core and residential setback-nonconformity applies, verify eligibility and prepare a variance request with required findings (§ 24.17.130.E; ).

Risks & Ambiguities

Plain-English Summary

If your building or use in Imperial doesn’t meet today’s zoning, you can usually keep using it—but changes are tightly limited. If you stop for 6 months, or if more than half the structure is destroyed, you’ll likely need to meet current rules. Some nonconforming uses must be phased out on a set schedule after you’re officially notified, with narrow exceptions for small CUP-approved expansions. When in doubt, check your district, your notice date, and whether any relief like a variance or Specific Plan applies to your site.

Source References

• Imperial Zoning Ordinance definitions of nonconforming use/lot/building (§ 24.01.180)
• Nonconforming Uses and Structures: Purpose, Continuation, Alterations, Discontinuation, Restoration, Elimination, Change, Effective Dates, Notice (§§ 24.17.110–24.17.195)
• Specific Plan Zone rules (§§ 24.09.320–24.09.330)
• Cross-references for permitted/conditional uses (R: § 24.03.110; C/I: § 24.05.120, § 24.07.120) — Not found in retrieved materials (see Imperial Land Use)

Retrieved passages

• Imperial Zoning Code (SECTION 24.17) High relevance show source text
• CBC § 24.17.140 (Section 24.17.140) High relevance show source text
• CBC § 24.01.180 (Section 24.01.180) High relevance show source text
• Imperial Zoning Code (Section 24.17.160.) High relevance show source text
• Imperial Zoning Code (Section 24.17.195) High relevance show source text
• Imperial Zoning Code (Section 24.17.195) High relevance show source text
• Imperial Zoning Code (Section 24.01.180) High relevance show source text
• Imperial Zoning Code (section shall) High relevance show source text

Cited sections

• Imperial Zoning Ordinance definitions of nonconforming use/lot/building (§ 24.01.180) (§ 24.01.180)
• Nonconforming Uses and Structures: Purpose, Continuation, Alterations, Discontinuation, Restoration, Elimination, Change, Effective Dates, Notice (§§ 24.17.110–24.17.195) (§ 24.17.110)
• Specific Plan Zone rules (§§ 24.09.320–24.09.330) (§ 24.09.320)
• Cross-references for permitted/conditional uses (R: § 24.03.110; C/I: § 24.05.120, § 24.07.120) — Not found in retrieved materials (see Imperial Land Use) (§ 24.03.110)
• Imperial_ZoningCode.md