Local zoning · Fontana

Fontana — Nonconforming Uses

Nonconforming Uses under the Fontana local zoning and planning code, with the controlling citations.

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Last reviewed: July 2, 2026

Overview

This page summarizes what the City of Fontana's Zoning and Development Code says about nonconforming uses, nonconforming structures, and nonconforming lots — what can continue, what must stop, and when repair/expansion is allowed. The rules are found primarily in the Development Code Divisions titled "Non‑Conforming Uses and Structures", the Form‑Based Code nonconforming rules, and the residential/commercial development standards tables; key provisions appear in § 30-350 through § 30-357, § 30-414, and the ADU rules at § 30-467.

Note: if you are planning work, also check Fontana's requirements for parking, development standards, and design review — these interact with nonconforming approvals.

Core rules (plain-English, code anchors)

  • Purpose: The City intends to limit and phase out harmful nonconformities while allowing lawful pre‑existing uses to continue where safe and practical — see § 30-350.

  • Enlargement / Moving:

    • A nonconforming use cannot be enlarged or intensified except if the Planning Commission approves a conditional use permit. No change of location on the lot is allowed from the area occupied on the effective date. § 30-351(a).
    • A nonconforming structure may not be moved, altered, or enlarged unless the change removes the nonconformity or is otherwise allowed by the Code. § 30-351(b).

  • Repair / Reconstruction after damage:

    • If reconstruction cost is less than 75% of replacement value (as determined by the Building Official), the structure may be restored and the nonconforming occupancy continued; if 75% or more, the building must be brought into full conformance with the zoning district rules. § 30-351(2).

  • Abandonment / Cessation:

    • A nonconforming use that is discontinued or changed to a conforming use for more than six months cannot be reestablished; the site must thereafter conform. Limited pauses for repairs/expansions are allowed but not longer than 24 months under some provisions. § 30-351(3).

  • Change of use:

    • A nonconforming use may not change except to a conforming use. The Planning Commission can allow one nonconforming use to change to another nonconforming use of equal or lesser intensity by conditional use permit after a public hearing. § 30-351(4).

  • Form‑Based Code / special exemptions:

    • The Code contains targeted rules for Form‑Based Code areas and for incremental improvements. The Planning Commission or the Director may authorize limited expansions and improvements under findings listed in § 30-352(d) and § 30-353, including administrative site plan approval for some additions. Key limits include: commercial additions up to 50%, industrial additions up to 10% (administrative exemption) and minor building expansions up to 10% under other findings. § 30-352(d); § 30-353(a); § 30-357(1).

  • Nonconforming lots:

    • A lot recorded before April 4, 1957, that does not meet current area/width/depth standards may still be occupied by any use permitted in the zone, subject to the Code; minimum street frontage of 20 feet is required to accommodate a residential use. § 30-414.

  • Parking‑specific nonconformance:

    • Where a use is nonconforming only because of off‑street parking, repairs are allowed but structural alterations are limited unless the Building Official finds them necessary for health/safety. Additions typically must meet current parking standards; vacancy for six months can bar reoccupancy until parking compliance is achieved. See Form‑Based Code rules § 30-357 and related provisions.

  • ADUs and nonconforming conditions:

    • The ADU rules make clear that the City will not deny an ADU/JADU permit solely because of a nonconforming zoning condition or a building code violation that does not threaten health/safety or is not affected by the ADU construction; an ADU that meets the ADU standards is not required to correct nonconforming zoning conditions. See § 30-467(b)(4) and related ADU provisions. For ADU practical limits, consult Fontana’s ADU rules and the California Building Standards Code.

District‑by‑district breakdown (how nonconforming rules interact with the City's districts)

Below are the primary Fontana districts that most frequently produce nonconforming situations. Each subsection summarizes the district purpose, typical permitted uses (short), key dimensional standards most relevant to nonconforming determinations, and where the district applies in the Code.

  • Note: the municipal code establishes the districts in Table No. 30-408; see that table and the individual development standards tables cited below. § 30-408.

R-E (Residential Estate)

  • Purpose & where listed: § 30-408 lists R-E as Residential Estate.
  • Typical uses: large‑lot single‑family, accessory structures, limited agriculture per Table No. 30-430. § 30-430.
  • Key dimensional standards: Table No. 30-434 shows maximum density 2.0 du/ac, minimum lot size 21,780 sq ft, and maximum lot coverage 45% for R‑E. If a lot predates the Code and is smaller, § 30-414 applies.
  • Nonconforming guidance: Residential nonconforming items (height/area) cannot be enlarged unless additions comply with the district standards (see § 30-351(9) and § 30-352(b)).

R-1 (Single‑Family Residential)

  • Purpose: standard single‑family neighborhoods (Table No. 30-434; § 30-434).
  • Typical uses: single‑family detached, ADUs allowed, accessory structures (see Table No. 30-430). § 30-430.
  • Key standards (Table 30-434): maximum density 5.0 du/ac, minimum lot width at front setback 60 ft, minimum lot size 6,000 sq ft (avg 7,200), max lot coverage 45%, minimum dwelling sizes (varies).
  • Nonconforming guidance: Small pre‑existing lots can remain under § 30-414; single‑family nonconforming structures are permitted limited repairs and specific accessory conversions (see § 30-352(b)). ADU rules at § 30-467 also apply and protect ADU approval from unrelated nonconforming zoning conditions.

R-2 / R-3 (Medium‑density / Multiple‑family Residential)

  • Purpose: higher densities and multi‑family options; additional development rules in § 30-444.
  • Typical uses: attached single‑family, multi‑family, planned unit developments (see Table No. 30-430). § 30-430.
  • Key standards: Table No. 30-434 provides density ranges (R‑2 up to ~12 du/ac depending on product), lot widths/depths, and max lot coverage ~50%; § 30-444 gives building separation and setback tables that matter when rebuilding or expanding nonconforming buildings.
  • Nonconforming guidance: Additions that increase floor area by 50% or more may trigger full compliance with Form‑Based or district standards (§ 30-357, § 30-357(1)(a)(2)). Repairs under the 75% damage rule still apply.

R-PC (Residential Planned Community)

  • Purpose & standards: planned community with customized site standards; Table No. 30-434 includes R‑PC columns (minimum lot sizes and coverage differ). § 30-434.
  • Nonconforming guidance: Projects under a specific R‑PC approval may have unique nonconforming consequences; verify the underlying planned community entitlement and § 30-414 for lots of record. Verify with the jurisdiction.

R-4 / R-5 Overlays (higher density overlays)

  • The City also has an R‑4 overlay intended to encourage affordable medium/high density housing; overlay provisions modify underlying standards and provide flexibility — see § 30-663.1 ff. Overlays alter how nonconforming setbacks or densities are treated (the overlay may change required setbacks). § 30-663.1 — § 30-663.3.

Commercial / Mixed‑Use: C-1, C-2, RMU, FBC

  • Purpose & uses: Tables No. 30-489 and 30-494 list permitted commercial uses, setbacks and parking rules for C‑1, C‑2, and RMU; the Form‑Based Code (FBC) districts are listed in Table No. 30-408. § 30-489, § 30-494, § 30-408.
  • Nonconforming guidance: For commercial or industrial nonconforming buildings the Director may permit limited additions and site improvements via administrative site plan § 30-353, subject to findings; otherwise additions often trigger full compliance (commercial additions ≤50%, industrial ≤10% under administrative exemption). Parking nonconformance is strictly managed — additions typically must meet current parking requirements.

Industrial: M‑1 / M‑2

  • Purpose: light and general industrial uses; permitted uses and setbacks appear under Article VII. Nonconforming industrial buildings have limited administrative expansion options (industrial additions ≤10% under special exemption § 30-353(a)(1)).

(For full district use tables and numeric setbacks, consult Table No. 30‑430, Table No. 30‑434, Table No. 30‑448, Table No. 30‑494 in the Code.)

Quick reference table — most decision‑relevant nonconforming standards

Topic Rule (plain‑English) Code reference
Purpose / overall approach City restricts, controls and aims to eliminate detrimental nonconformities § 30-350
Enlargement of nonconforming use Cannot be enlarged or intensified without Planning Commission (CUP) § 30-351(a)(1)
Move/alteration of nonconforming structure Not allowed unless it eliminates the nonconformity or as otherwise provided § 30-351(b)
Damage/repair threshold Repairs allowed if reconstruction cost < 75% of replacement value; ≥75% requires full compliance § 30-351(2)
Abandonment / cessation 6 months continuous cessation → nonconforming use ends; limited exception up to 24 months for repairs/expansions under certain sections § 30-351(3)
Administrative exemptions (commercial/industrial) Commercial additions ≤ 50%; industrial additions ≤ 10% (Director, admin site plan) § 30-353(a)(1)
Form‑Based Code additions Additions ≥ 50% of floor area trigger compliance for that portion § 30-357(1)(a)(2)
Nonconforming lot rule Lots of record before 4/4/1957 may be used; minimum street frontage 20 ft for residential § 30-414
ADUs & nonconforming zoning ADU/JADU permits cannot be denied solely for nonconforming zoning conditions not affecting health/safety § 30-467(b)(4) and ADU subsections

Checklist — what an applicant must satisfy to alter / repair / expand a nonconforming use/structure

  • Confirm that the existing use/structure was lawfully established and is a legal nonconforming condition (not an illegal/unpermitted use) — see § 30-353(c)(1).
  • Obtain current determination of replacement value from the Building Official if making repairs after damage (to apply the 75% rule) — § 30-351(2).
  • If enlargement/intensification of a nonconforming use is proposed, prepare a Conditional Use Permit application for Planning Commission review (unless an administrative exemption explicitly applies) — § 30-351(a)(1).
  • For small commercial/industrial additions, prepare an administrative site plan showing compliance with the findings in § 30-353 (and include parking, drainage, and fire protection compliance). § 30-353(a–c).
  • Demonstrate compliance with parking rules (number of spaces) if the nonconformity involves parking; if adding floor area, show additional spaces or explain equivalency to the Director — see Form‑Based Code and Table No. 30‑455. Fontana Parking § 30-357.
  • If located inside a Form‑Based Code area, follow the Form‑Based Code nonconforming procedures and design/admin review rules — see § 30-355 and § 30-357.
  • If the work triggers design review or administrative site plan thresholds (size, new construction, façade changes), file the appropriate design review application and plans. Fontana Design Review § 30-356.
  • If proposing an ADU/JADU, follow § 30-467 and note ADU protections for nonconforming zoning conditions; include building permits and any demolition permit reviewed with the ADU application. Fontana ADUs § 30-467.
  • Verify whether overlay districts (e.g., R-4 overlay) modify standards on the parcel and whether special overlay findings apply. Fontana Overlay Districts § 30-663.1.
  • Confirm that any work meets state building code requirements; the Building Official enforces building code thresholds such as when an alteration constitutes a full code upgrade. See California Building Standards Code.

Risks & Ambiguities

Issue Why it matters What to verify
Is the use truly "legal‑nonconforming"? Only lawful prior uses get protection; illegal/unpermitted uses have no protected status. Confirm historic permits/records and get the Planning Department to confirm legal nonconforming status (see § 30-353(c)(1)).
Damage valuation (the 75% test) Whether reconstruction requires full compliance hinges on the Building Official’s replacement‑value determination. Get an early cost estimate and ask the Building Official for the replacement‑value determination procedure under § 30-351(2).
Does the proposed work trigger a full compliance requirement (e.g., 50% addition rule)? Additions past thresholds convert the project into a conforming rebuild or require compliance with district/Form‑Based Code standards. Check § 30-357(1)(a)(2) and § 30-353; calculate percent increase precisely and verify which square footage baseline applies.
Parking nonconformance (re‑occupancy after vacancy) Vacancy periods and parking shortfalls can block re‑occupancy or require full parking upgrades. Confirm whether the use is only parking‑nonconforming and whether vacancy exceeded 6 months (Form‑Based Code rules § 30-357(1)(b–c)).
Overlay / Form‑Based Code applicability Form‑Based Code provisions can supersede other sections and have distinct nonconforming rules. Verify whether the parcel is inside the FBC boundary and apply § 30-355 / § 30-357 (Figure maps referenced in the Code may be omitted from online excerpts).
ADU interactions with nonconforming zoning ADU statutes and § 30-467 limit Fontana’s ability to require correction of unrelated nonconformities when permitting ADUs. If building an ADU, reference § 30-467(b)(4) and consult ADU checklist; if health/safety issues exist, City may still require corrections.

Plain‑English Summary

Fontana lets lawful pre‑existing uses and buildings keep operating, but they can’t be expanded or moved around freely; small repairs and limited incremental improvements are allowed, while major rebuilds or additions typically require bringing the property into compliance with the current zoning rules. Key triggers are: a six‑month abandonment rule, a 75% damage/rebuild threshold, and percentage‑of‑addition thresholds (e.g., 50% for some types) that force compliance — see § 30-351, § 30-352, § 30-353, and § 30-357.

Information Gaps

  • The Code excerpts in the retrieved materials omit the full map graphics and some figure‑based boundaries (e.g., Form‑Based Code maps and Figure 1 for R‑4): parcel‑specific applicability of overlays must be confirmed with the jurisdiction (map not found in materials). Verify with the City.
  • Fee schedules, application forms, and exact administrative processing timelines for nonconforming administrative exemptions are not reproduced here; check Planning Department application checklists. Not found in retrieved materials.
  • Practical valuation method used by the Building Official for the 75% reconstruction test (e.g., inclusion/exclusion of sitework) — procedural detail not included; verify with Building Official. Not found in retrieved materials.

Source References

  • § 30-350 — Purpose (Non‑Conforming Uses and Structures).
  • § 30-351 — Nonconforming regulations: repairs, moving, restoration, abandonment, change of use, etc.
  • § 30-352 — Exemptions (continuance; residential exemptions).
  • § 30-353 — Special exemption / administrative site plan approval for improvements to nonconforming buildings/sites.
  • § 30-357 — Nonconforming regulations for Form‑Based Code districts.
  • § 30-414 — Nonconforming lot size (lots of record rule; 20 ft frontage minimum for residential).
  • Table No. 30-430 — Uses permitted (residential districts).
  • Table No. 30-434 — Residential development standards (R‑E, R‑1, R‑2, R‑3, R‑PC).
  • § 30-444 — Additional development standards for R‑2 and R‑3.
  • § 30-353, § 30-357 — Administrative exemptions and Form‑Based Code triggers for additions and parking.
  • § 30-467 — Accessory Dwelling Unit (ADU) rules and the City’s treatment of nonconforming zoning conditions for ADUs. Fontana ADUs § 30-467.
  • For guidance on ADU state interactions and nonconforming zoning protections see the California ADU handbook excerpts included in the materials.

Sources

Retrieved passages

  • Fontana Zoning Code (article is) High relevance
  • Fontana Zoning Code (article herein) High relevance
  • Fontana Zoning Code (chapter and) High relevance
  • Fontana Zoning Code (article herein.) High relevance
  • Fontana Zoning Code (article or) High relevance
  • Fontana Zoning Code (article or) High relevance
  • Fontana Zoning Code (section shall) High relevance
  • Fontana Zoning Code (section regulates) High relevance
  • Fontana Zoning Code (§ 11) Medium relevance
  • Fontana Zoning Code (Section 30-444) Medium relevance
  • Fontana Zoning Code (Section 30432.) Medium relevance
  • Fontana Zoning Code (Section 30-461) Medium relevance
  • Fontana Zoning Code (§ 8) Medium relevance
  • Fontana Zoning Code (chapter to) Medium relevance
  • Fontana Zoning Code (Article II) Medium relevance
  • Fontana Zoning Code (§ 8) Medium relevance
  • Fontana Zoning Code (§ 66314) High relevance
  • Fontana Zoning Code (§ 66333) Medium relevance
  • CPC § 17920.3 (Section 30-467) Medium relevance
  • CPC § 66000 (§ 66000) Medium relevance
  • Fontana Zoning Code (§ 8) Medium relevance
  • Fontana Zoning Code (Chapter 11) Medium relevance
  • CFC § 66323 (§ 66323.) Medium relevance
  • Fontana Zoning Code (§ 66314) Medium relevance

Cited sections

Frequently asked questions

How does Fontana define a nonconforming use or structure?

Fontana treats a nonconforming use/structure as a lawful pre‑existing use or building that no longer conforms to the current Zoning and Development Code; the purpose and general rules are stated in § 30-350 and the detailed regulations in § 30-351.

Can I enlarge a nonconforming commercial building in Fontana?

Only in limited cases: large enlargements typically require the Planning Commission (conditional use permit) or full compliance; the Director may allow administrative exemptions for commercial additions up to 50% under the findings in § 30-353(a)(1). Verify the exact path with the Planning Department.

If my building is 80% destroyed by fire, can I rebuild to its prior footprint?

No — if the cost to reconstruct is 75% or more of replacement value (Building Official determination), the building must be rebuilt to meet current Code (no mere return to the prior nonconforming condition) as stated in § 30-351(2).

What happens if a nonconforming use stops for more than six months?

If a nonconforming use is discontinued or abandoned for six months continuously, it may not be reestablished — the property must thereafter conform to applicable district regulations (§ 30-351(3)). Some limited repair/expansion time allowances exist but generally not beyond 24 months in certain provisions.

Does a small nonconforming lot prevent me from building in Fontana?

No automatic bar — lots of record before April 4, 1957 that are smaller than current minima may still be used for permitted uses subject to Code rules; for residential uses there must be at least 20 ft of street frontage (see § 30-414) and building setbacks of the district apply. Verify parcel history and frontage.

If my business lacks required parking, can I remodel?

Repairs are permitted but structural alterations are limited unless the Building Official finds them necessary for safety; additions generally must meet parking standards — the Form‑Based Code nonconforming parking rules are in § 30-357 (including vacancy consequences). Review required parking in Table No. 30‑455 and consult Fontana Parking.

Will Fontana deny an ADU because of unrelated nonconforming zoning?

No — the ADU section makes clear an ADU/JADU permit will not be denied solely because of a nonconforming zoning condition or building code violation that does not threaten health/safety or is not affected by the ADU work; see § 30-467(b)(4) and related ADU subsections. Fontana ADUs

What percent addition forces full compliance under the Form‑Based Code?

In Form‑Based Code areas an addition equal to or greater than 50% of the existing floor area will typically trigger compliance with Form‑Based Code district provisions for the added portion, per § 30-357(1)(a)(2).

Who decides whether a proposed improvement to a nonconforming building is allowed administratively?

The Director of Planning can approve limited exemptions via administrative site plan if the findings of § 30-353(c) are met; the Planning Commission may handle larger/conditional requests or forward them to City Council.

Where are the numeric setback and lot standards I should use to check compliance?

Residential development numeric standards are in Table No. 30-434 (R‑E, R‑1, R‑2, R‑3, R‑PC) and additional building separation/setbacks appear in § 30-444 and Table No. 30-448. Use those tables to check district dimensional conformity. § 30-434, § 30-444, Table No. 30‑448. ---

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