Riverbank — Nonconforming Uses

Last reviewed: July 2, 2026

Overview

This page explains how the City of Riverbank handles nonconforming uses, nonconforming structures, and nonconforming lots under its zoning ordinance (commonly known as Title 15/Chapter 153 in the City's code). It summarizes the continuing rights, limits on expansion or repair, administrative paths for changes, and special rules (for example, towers) that apply in Riverbank. For related procedural and technical rules also consult the city's Riverbank Zoning overview and the city's Riverbank Development Standards. If your application will affect vehicle access or parking, review the city's Riverbank Parking rules early.

Core rules (what the code actually requires)

• A lawful use that was in place when the current zoning chapter was adopted may be continued even if it no longer conforms to the zoning rules for the district; but enlargement, intensification, or extension is limited unless authorized (see § 153.195 and § 153.196) .
• Enlargement, relocation on the lot, remodeling beyond ordinary maintenance, or adding area to a nonconforming structure requires a permit and findings by the Planning Commission (criteria in § 153.195) .
• A nonconforming use may be changed to a use of the same or more restricted nature only after a use permit is obtained (§ 153.198) .
• If a nonconforming use ceases for a continuous period of six months, it is presumed abandoned and the property must thereafter conform to current zoning (§ 153.199) .
• A nonconforming building damaged or destroyed to an extent exceeding 75% of its appraised value may be restored only by making it conform to the district rules — except that a use permit may allow restoration of floor area not to exceed the former building (§ 153.200) .
• Ordinary maintenance is permitted; structural alterations are limited so that such work does not exceed 15% of appraised value in any one-year period without a use permit (§ 153.201) .
• The City allows a limited, administrative minor expansion of legal nonconforming single‑family dwellings or duplexes up to 25% of existing floor area with Community Development Director approval (see § 153.203) .
• The wireless-tower/antenna chapter contains a separate nonconforming rule set and some exceptions (see § 153.344 for towers and antennas) .

Below is a quick-reference table of the most decision-relevant items.

District-by-district breakdown

The Riverbank code organizes the city into zones; where district-specific rules exist they determine what constitutes a nonconformity and what repairs or changes are allowed. The ordinance lists the districts (map and names) and explains where boundaries are interpreted; see § 153.012 and § 153.015 for map/adoption and boundary rules .

Below are the districts commonly involved in nonconforming‑use questions and what the Riverbank code itself states about each. Where the ordinance text available to us did not include a full use table or dimensional standard for a district, that is called out and you should Verify with the jurisdiction.

R-1 (Single-Family Residential)

• Purpose: Standard single‑family residential lots and their accessory uses per the R‑1 rules (§ 153.030). § 153.031 lists permitted uses, including one single-family dwelling or one manufactured home (with limitations) and accessory buildings .
• Typical permitted uses: single-family dwelling, manufactured home (with conditions), accessory buildings, and limited home occupations (§ 153.031) .
• Key dimensional standards: The ordinance establishes R‑district yard and lot standards (front/side yards, lot coverage, etc.) in the R‑district sections; specific numbers for front yard, side yard, lot coverage and minimum lot depth appear in the R‑zone provisions in the code (see the R‑zone regulations for details) — the code requires review of the R‑zone rules for exact values (§ 153.030, related R‑zone subsections) .
• Where it applies: All areas mapped R‑1 on the Riverbank Zoning Map; boundary questions resolved per § 153.015 .
• Nonconforming implications: A preexisting nonconforming dwelling may continue, minor expansion up to 25% permitted via Director approval under § 153.203 for single‑family/duplex units; larger changes require the Commission permit/findings under § 153.195 .

R-2 (Two-Family / Medium-Density Residential)

• Purpose & uses: Not fully reproduced in the retrieved materials for this search. The ordinance indicates R‑districts are arranged from most to least restrictive (R‑1 then P‑D, R‑2, R‑3, etc.) but the detailed R‑2 use list and numeric standards are Not found in retrieved materials. Verify with the City’s R‑2 section on the zoning map and code (§ 153.012) .

R-3 (Multiple-Family Residential)

• Purpose: Multiple-family development standards appear under § 153.060 and related subsections; uses permitted include single-family, duplex, multiple family, apartments and related accessory uses (§ 153.061) .
• Typical permitted uses: apartments, dwelling groups, manufactured home (in lieu of residential uses under constraints), accessory buildings, and certain temporary uses — see § 153.061 for full list .
• Key dimensional standards: R‑3 regulations are stated in the R‑3 section; specific numeric standards (setbacks, lot coverage, minimum building sizes) are provided in the code — see § 153.060/61 for the R‑3 regulatory framework .
• Nonconforming implications: Same citywide nonconforming rules apply (continuation, no enlargement without permit, abandonment, damage/repair thresholds) per §§ 153.195–153.201 .

CX-1, C-1, C-2, C-M (Commercial)

• Purpose & uses: These commercial districts are listed in the ordinance and carry progressively broader permitted uses than R‑districts (the code notes a sequencing of districts where R‑1 is most restrictive, followed by P‑D, R‑2, R‑3, CX‑1, C‑1, C‑2, C‑M, M‑1, M‑2 — see § 153.012) .
• Typical permitted uses: Full, code‑section‑specific lists exist in the commercial chapter(s) of the code (not all excerpts were retrieved here). For any commercial nonconforming use, apply the general nonconforming-use rules §§ 153.195–153.201; where the code has special deemed‑approved alcohol sale rules they are layered on top (see the alcohol regulations referencing the nonconforming rules) .
• Key dimensional standards: Not found in retrieved materials for every commercial district; verify exact yard, coverage, and parking requirements in § chapters for each commercial zone and the Riverbank Development Standards page.

C-M, M-1, M-2 (Industrial / Manufacturing)

• Purpose & uses: Industrial districts are included in the zoning hierarchy and have specific use lists and standards in their respective sections; detailed numeric standards were Not found in the returned excerpts. Apply the citywide nonconforming rules §§ 153.195–153.201; special facility types like towers have separate nonconforming rules (§ 153.344) .

P‑D (Planned Development)

• Purpose & uses: P‑D is used as a more flexible, plan‑based zone; the code lists it in the district order but specific P‑D standards and how nonconforming situations are handled are Not found in retrieved materials. Verify with the City's P‑D ordinance language and the zoning map (§ 153.012) .

Special topic: Towers and Antennas

• The wireless facilities chapter provides its own nonconforming language: preexisting towers may continue and routine maintenance or replacement in kind is allowed; rebuilding after damage has an exception but must comply with rebuilding deadlines and building codes — see § 153.344 and related provisions for operational rules and time limits (e.g., 180 days for a rebuild permit) .

How the City decides an expansion or repair request (practical guide)

If you seek to enlarge, relocate, or structurally alter a nonconforming building or extend a nonconforming use:

1. Expect an application (use permit or Planning Commission permit) and a public hearing if the change is beyond ordinary repair. The Planning Commission must find the enlargement will not unreasonably burden nearby lands, will not be detrimental to public health and safety, and is logically related to the existing use (§ 153.195) .

2. Minor residential expansions (SFD/duplex) of up to 25% floor area can be processed administratively by the Community Development Director — they must still comply with other city code requirements and not create additional units (§ 153.203) .

3. Ordinary maintenance and non‑structural repairs are allowed; structural alterations exceeding the 15% annual appraised‑value cap need a use permit (§ 153.201) .

4. If a nonconforming property has been unused for six months, the City treats the use as abandoned and you must thereafter comply with current zoning (§ 153.199) .

5. If the structure is damaged (> 75% of appraised value), restoration is limited — either conform to current standards or secure a use permit that expressly allows limited restoration (§ 153.200) .

Before filing, coordinate early with Community Development staff and review any applicable overlay district rules at the Riverbank Overlay Districts and design standards at the Riverbank Design Review page, since such overlays or review processes can affect allowable changes.

Checklist (what an applicant must generally show)

• Identify the current lawful nonconforming use or feature and show it existed prior to the adoption/amendment date (documentation, photos, business licenses, historic permits).
• Demonstrate that proposed enlargement or change will not increase the occupied area beyond the preexisting footprint unless you secure a Planning Commission permit under § 153.195 .
• If changing use, provide a use‑permit application showing the new use is of the same or more restricted nature (or justify requested change) per § 153.198 .
• If the building was damaged, provide an appraisal and cost estimate to determine the >75% threshold; if >75% you must show conformance or a successful use‑permit justification (§ 153.200) .
• For repairs/alterations, supply cost estimates to confirm the annual 15% threshold under § 153.201; if exceeded, submit a use permit application with plans and environmental review info as required (§ 153.201, § 153.212–214) .
• For minor residential expansions (≤25%), submit a Director application showing compliance with other development standards and no new units will be created (§ 153.203) .
• Check parking implications early and consult the city's Riverbank Parking rules; verify whether the proposed change triggers design review or overlay requirements (Riverbank Design Review and Riverbank Overlay Districts).

Risks & Ambiguities

Plain-English Summary

If your Riverbank property or business was legal when the current zoning took effect, you generally can keep operating, but you cannot enlarge or intensify that nonconforming use without City approval; limited repairs are allowed, some small residential expansions are administratively permitted, and long-term cessation (six months) or severe damage (over 75% of value) can force you to rebuild to today’s rules (§§ 153.195–153.203) .

Source References

• Riverbank Municipal Code — Nonconforming uses and structures: § 153.195 through § 153.203 (Use of land; continuation; use permits; abandonment; damaged building; repair limits; minor expansion). § 153.195 – § 153.203
• Riverbank Municipal Code — R‑zone establishment and map rules: § 153.012, § 153.015 (zoning map & boundary interpretation)
• Riverbank Municipal Code — R‑1 district regulations and permitted uses: § 153.030, § 153.031 (R‑1 permitted uses and standards)
• Riverbank Municipal Code — R‑3 district regulations and permitted uses: § 153.060, § 153.061 (R‑3 permitted uses and standards)
• Riverbank Municipal Code — Towers and antennas, nonconforming rules: § 153.344
• Riverbank Municipal Code — Administrative procedures and application requirements (permitting & supporting information): § 153.210 – § 153.214
• (Context — state ADU guidance, uploaded for reference only; the Riverbank ordinance excerpts do not attempt to regulate ADU vs nonconforming issues here) — 2025 California ADU handbook (uploaded)

Retrieved passages

• Riverbank Zoning Code (§ 10-14-1) High relevance show source text
• Riverbank Zoning Code (§ 153.198) High relevance show source text
• Riverbank Zoning Code (§ 153.185) High relevance show source text
• Riverbank Zoning Code (§ 110.18) High relevance show source text
• CBC § 10.99 (section may) Medium relevance show source text
• CBC § 10.99 (section may) Medium relevance show source text
• Riverbank Zoning Code (§ 153.092) Medium relevance show source text
• Riverbank Zoning Code (§ 153.364) Medium relevance show source text

Cited sections

• Riverbank Municipal Code — Nonconforming uses and structures: **§ 153.195** through **§ 153.203** (Use of land; continuation; use permits; abandonment; damaged building; repair limits; minor expansion). **§ 153.195 – § 153.203** (§ 153.195)
• Riverbank Municipal Code — R‑zone establishment and map rules: **§ 153.012**, **§ 153.015** (zoning map & boundary interpretation) (§ 153.012)
• Riverbank Municipal Code — R‑1 district regulations and permitted uses: **§ 153.030**, **§ 153.031** (R‑1 permitted uses and standards) (§ 153.030)
• Riverbank Municipal Code — R‑3 district regulations and permitted uses: **§ 153.060**, **§ 153.061** (R‑3 permitted uses and standards) (§ 153.060)
• Riverbank Municipal Code — Towers and antennas, nonconforming rules: **§ 153.344** (§ 153.344)
• Riverbank Municipal Code — Administrative procedures and application requirements (permitting & supporting information): **§ 153.210 – § 153.214** (§ 153.210)
• (Context — state ADU guidance, uploaded for reference only; the Riverbank ordinance excerpts do not attempt to regulate ADU vs nonconforming issues here) — 2025 California ADU handbook (uploaded)
• Riverbank_ZoningCode.md
• 2025 California ADU handbook.md

• Official Riverbank code library