Local zoning · Isleton

Isleton — Signage

Q: How much signage can I have on a downtown storefront in Isleton?

For a CC/CCRD storefront the code allows a minimum of 50 sq ft for a primary frontage and a calculated maximum of 2 sq ft per linear foot of primary frontage up to 350 sq ft (secondary frontage rules differ: 35 sq ft min; 1 sq ft per linear foot up to 200 sq ft ). § 1204.D.2

Q: What are the rules for signs in industrial zones?

Industrial sites may use either 1 sq ft per lineal foot of property line adjacent to a street or 100 sq ft per acre of site area (whichever is greater) up to a 600 sq ft cap; temporary non‑verbal signs (banners/flags) are limited to 10% of that maximum or 60 sq ft . § 1204.E.1–E.2

Q: If a sign obstructs sight lines at an intersection, what is allowed?

Signs are generally prohibited within 30 ft of an intersection (intersecting curb lines) unless the top is at most 2½ ft off the ground or the bottom is at least 10 ft above ground; this is to protect sight distance and safety. § 1204.B.16

Signage under the Isleton local zoning and planning code, with the controlling citations.

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Last reviewed: July 2, 2026

Overview

Isleton regulates signs in its Zoning Code (Title 17) under Article 12 — Signs and Outdoor Advertising with the principal sign rules collected in § 1204. The rules set measurement rules, per‑district allowable areas (with especially detailed limits for the central commercial district), mounting/projection limits, temporary sign rules, prohibited sign types, and review/appeal procedures; permanent signs typically need Planning Commission approval while limited temporary signs are administratively handled. See the code for how signs interact with site design rules such as parking, setbacks/development standards, and design review for project approval. § 1204

How the ordinance is organized (short)

Base authority: Title 17 — Zoning (the zoning code) governs signs as part of the development standards included in the zone regulations and in Article 12; the sign rules themselves are in § 1204. § 101, § 104, § 1204
Review: Permanent and most non‑temporary signs are subject to Planning Commission review; temporary signs may be permitted at the city administration level. § 1204.D.21

Note: This page only covers the Zoning/Sign rules in Title 17. For construction or electrical requirements for illuminated signs consult the California Building Standards Code. California Building Standards Code (/us/california/building-codes)

District-by-district breakdown (what sign rules actually differ by district)

CC / CCRD / Central Commercial (Commercial districts)

Purpose and where it applies

The CC (central commercial) and CCRD (central commercial/residential) zones concentrate retail, service and office uses; sign rules are tailored to encourage coherent storefront signage and to avoid clutter. Secs. 801–804; § 1204.D

Key permitted sign standards (high‑priority items)

Primary building frontage: minimum allowable sign area up to 50 sq ft; maximum based on 2 sq ft per linear foot of primary frontage but no more than 350 sq ft total for a primary frontage. § 1204.D.2
Secondary frontage: minimum 35 sq ft; maximum 1 sq ft per linear foot to a limit of 200 sq ft for secondary frontages. § 1204.D.2
Painted wall signs count toward allowable area. § 1204.D.8
Projection limits: projecting signs (except directional) may not project more than 24 inches into required rear or interior side yards; into public ROW, typically max 14 inches (except marquees). § 1204.B.5; § 1204.D.5

Typical process and interaction

Because CC/CCRD developments often require site plan or design review, plan submittals must show sign area calculations and compatibility with façade design; see design review and development standards pages. § 1204.D; § 1505.D

C (other commercial districts) (general C districts)

The general commercial rules in § 1204.D apply to any permitted or conditional use in a C district; purpose is described as avoiding clutter and encouraging replacement of non‑conforming signs. § 1204.D.1

I (Industrial districts)

Purpose and where it applies

Industrial sites have a distinct allowance to accommodate larger sites but with tighter controls on off‑site/outdoor advertising. Sec. 906; § 1204.E

Key standards

Allowed sign area: the maximum aggregate area equals 1 sq ft per lineal foot of property line adjoining a street OR 100 sq ft per acre of site area in use, whichever is greater, up to a 600 sq ft cap. § 1204.E.1
Temporary non‑verbal banners/flags/window displays limited to 10% of max aggregate sign area or 60 sq ft, whichever applies. § 1204.E.2
Specific small signs allowed: one non‑illuminated sale/lease sign (up to 16 sq ft), directional signs (≤ 6 sq ft) and a 20 sq ft bulletin board for a public assembly site. § 1204.E.3‑5

R / RM (Residential and Multi‑Family districts)

Where it applies

Residential zones permit very limited signage and defer to § 1204 for exact allowances; many residential subsections simply reference the sign rules in § 1204 and limit signs to small non‑illuminated nameplates or permitted home‑occupation nameplates. See R and RM district provisions. § 601—705; § 1204; § 1201.12

Key standards

Home occupation/name plate: one non‑illuminated name plate up to 2 sq ft. § 1201.12
Non‑residential identification signs attached flat to a wall in residential districts: up to 16 sq ft (non‑illuminated). § 1204.C.2

Mobile home parks / RM‑MH / RM‑PD‑MH

Mobile home parks have a dedicated subsection § 1203. A park may have one identification sign at its entrance not exceeding 32 sq ft or 8 ft in height; landscaping at the base is required. Additional directional signs inside the park require Building Official approval. § 1203.C.9

Citywide / other special rules

A‑board (sidewalk) signs: permitted citywide in commercial districts with limits — max height 5 ft, min 2 ft, max width 3 ft, must allow 48 inches clear sidewalk, not block disabled access, and only during business hours. § 1204 (A‑board rules)
Prohibited signs: glaring/flashing signs, permanent outdoor advertising structures (billboards), signs using red/green/amber in positions that could be confused with traffic signals, open‑reverse letter signs, suspended banners across property (with civic event exceptions). § 1204.B.18; § 1204.D.18
Sight lines: no sign within 30 ft of an intersection unless it is below 2½ ft tall, or the bottom is at least 10 ft above ground. § 1204.B.16

Quick standards table (decision‑relevant)

Standard / item	Rule / limit	Code reference
Primary frontage sign allowance (CC)	Min 50 sq ft allowed; up to 2 sq ft per linear ft; cap 350 sq ft per primary frontage	§ 1204.D.2
Secondary frontage (CC)	Min 35 sq ft allowed; 1 sq ft per linear ft; cap 200 sq ft	§ 1204.D.2
Projecting signs into ROW	Max 14 inches (except marquees); into rear/interior side yards 24 inches	§ 1204.B.5; § 1204.D.5
Marquee/canopy signs	Max 6 sq ft per face; min clearance 8 ft above sidewalk	§ 1204.D.7
A‑board / sidewalk signs	Height 2–5 ft, width ≤ 3 ft, sidewalk clearance 48 in, only business hours	§ 1204 (A‑board rules)
Industrial district max aggregate	1 sq ft per lineal ft adjoining street OR 100 sq ft/acre, whichever greater, cap 600 sq ft	§ 1204.E.1
Mobile home park ID sign	Single entrance sign ≤ 32 sq ft and ≤ 8 ft tall with landscaping	§ 1203.C.9
Temporary sign removal timeline	Temporary event signs removed within 7 days after event; banners removed 14 days after event completion	§ 1204.D.10; § 1204.D.11
Prohibited types	Billboards (permanent outdoor advertising), flashing/glaring signs, open‑reverse letters, traffic‑confusing colors	§ 1204.B.18; § 1204.D.18

Practical guidance / plain-English interpretation (policy + practice)

If you run a storefront in downtown/CCRD, first measure your primary building frontage linear feet, compute 2 sq ft per linear ft (but know the city sets minimum and caps: 50 sq ft min, 350 sq ft max), and include painted murals in your area calculation — then design signs to match façade proportions and show this on your sign plan. § 1204.D.2, § 1204.D.8
Expect Planning Commission review for any permanent or larger sign; if you need a small temporary banner or an A‑board, those are handled administratively but still must follow size/placement rules and must not obstruct pedestrian access. § 1204.D.21; A‑board rules § 1204
For large industrial sites, calculate the permitted aggregate area using the property frontage method or acreage method, then check the 600 sq ft cap and the 10% rule for temporary banners. § 1204.E.1‑2
Avoid any illuminated colors or placements that could be confused with traffic signals and avoid flashing/glaring illumination — those are expressly prohibited. § 1204.B.18

Linkages: signs frequently intersect other approvals — show sign locations on parking, site plan and façade drawings so reviewers can check sight lines and pedestrian clearance. See the city's pages on parking, development standards, design review, overlay districts, historic preservation, landscaping and screening, and ADUs for related requirements and review triggers. (/us/california/isleton/parking) (/us/california/isleton/development-standards) (/us/california/isleton/design-review) (/us/california/isleton/overlay-districts) (/us/california/isleton/historic-preservation) (/us/california/isleton/landscaping-and-screening) (/us/california/isleton/adu)

Checklist (what an applicant must satisfy for a permanent sign in most commercial cases)

Identify zoning district for the site and applicable overlay(s); confirm CC/CCRD/C/I/RM status. § 1204; district sections
Measure primary and secondary building frontage (linear feet) and compute allowed sign area (document math). § 1204.D.2
Produce scaled elevation(s) showing sign face area, copy, location, projection, clearance, and construction details (materials/illumination). § 1204.B.2‑7
Demonstrate compliance with projecting/ROW/sidewalk clearance, sight‑triangle limits, and A‑board rules (if applicable). § 1204.B.5; § 1204.B.16; A‑board rules § 1204
Provide lighting/illumination plan (show no flashing/glaring, and no confusion with traffic signals). § 1204.B.18; § 1505.C
Submit sign permit application and pay fee; for permanent signs expect Planning Commission review and findings per site plan or design review if part of a larger project. § 1204.D.21; § 1505.D

Risks & Ambiguities

Issue	Why it matters	What to verify
Exact frontage measurement method for multi‑frontage properties	Sign area caps/minimums depend on primary vs secondary frontage	Confirm which façade is the "primary building frontage" with Planning staff; cite § 1204.D.2
Whether a particular banner counts toward aggregate area	Temporary banners sometimes are limited by district‑specific aggregate or by a % allowance	Check district subsection (e.g., CC vs I) and temporary sign rules; verify whether the banner is a permitted temporary event banner. § 1204.D.10‑11; § 1204.E.2
Historic district or overlay controls	Historic or overlay districts may impose stricter design review or limits that Supplement § 1204	Confirm overlay or historic‑preservation design standards and whether alternate sign types require Certificate of Appropriateness. Verify with the city's overlay and historic preservation pages. § 1204; overlay/historic sections Not found in retrieved materials — verify with jurisdiction
Nonconforming / existing signs	Nonconforming signs have special limits on alterations and replacement	If sign pre‑dates current code, see nonconforming sign rules and the process/limits for alterations. § 1308 (nonconforming signs)
Interaction with pedestrian ADA clearances (sidewalk signs)	A‑boards and sidewalk signs can create liability and ADA issues if clearance is mis‑measured	Verify exact sidewalk width and ADA path with Public Works/Building Official and ensure 48 inch clear path per § 1204 A‑board rules. § 1204 (A‑board)

Plain-English Summary

Isleton's sign rules (Title 17, principally § 1204) control how big, where, and what kind of signs you can have depending on the zoning: downtown commercial sites get the biggest allowances but must follow area caps (e.g., 350 sq ft max primary frontage), industrial sites use frontage or acreage methods up to 600 sq ft, residential uses are limited to small non‑illuminated nameplates, and many permanent signs require Planning Commission approval; temporary banners/A‑boards have specific size/location rules and short removal timelines. § 1204; § 1203; § 1201.12

Source References

Isleton Zoning Code — Title 17 (Zoning); adoption and code components — § 101, § 104.
Isleton Zoning Code — Article 12: Signs and Outdoor Advertising — § 1204 (regulation of signs, measurement, CC district limits, prohibitions, temporary sign rules, A‑board rules, industrial district rules, appeals). § 1204.
Isleton Zoning Code — Sec. 1203 (Mobile home parks — entrance sign limitation 32 sq ft / 8 ft). § 1203.C.9.
Isleton Zoning Code — Article 13 / § 1308 (nonconforming signs / procedures referenced in sign rules). § 1308.
Isleton Zoning Code — Site plan / design review and required findings (planning commission finds signage complies) — § 1505 / § 1506. § 1505.D.
A‑board / sidewalk sign specifics and portable sign prohibitions — § 1204 (A‑board rules).
For construction/electrical/structural details that affect illuminated signs consult the California Building Standards Code (state Title 24 / sign construction references). 2025 California Building Code (Appendix H on signs)

Sources

Retrieved passages

Isleton Zoning Code (section by) High relevance
Isleton Zoning Code High relevance
Isleton Zoning Code (article 14.) High relevance
Isleton Zoning Code (section shall) High relevance
Isleton Zoning Code (article 15.) High relevance
Isleton Zoning Code (§ 1) Medium relevance
Isleton Zoning Code (Title 17) Medium relevance
Isleton Zoning Code (section by) Medium relevance
Isleton Zoning Code (section shall) Medium relevance
Isleton Zoning Code (article 15.) Medium relevance
Isleton Zoning Code (section 604.F.3) Medium relevance
Isleton Zoning Code (article 15.) Medium relevance

Cited sections

Official Isleton code library

Frequently asked questions

What counts as “sign area” in Isleton?

Isleton computes sign area using the minimum imaginary rectangle or parallelogram enclosing the letters/panel; both sides are counted for two‑faced free‑standing signs and painted wall signs do count toward allowed area in C districts. See the computation rules in § 1204.B.2–B.2.e. § 1204.B.2–B.2.e

How much signage can I have on a downtown storefront in Isleton?

For a CC/CCRD storefront the code allows a minimum of 50 sq ft for a primary frontage and a calculated maximum of 2 sq ft per linear foot of primary frontage up to 350 sq ft (secondary frontage rules differ: 35 sq ft min; 1 sq ft per linear foot up to 200 sq ft). § 1204.D.2

Do I need Planning Commission approval for a new permanent sign?

Yes — permanent signs and most signage other than limited temporary signs are reviewed and approved by the Planning Commission; temporary signage is permitted at the city administration level on permit. § 1204.D.21

Can I put an A‑board on the sidewalk outside my business?

A‑board (sidewalk) signs are allowed citywide in commercial districts with restrictions: max 5 ft height, min 2 ft, max 3 ft width, must allow 48 in of unobstructed sidewalk, and are only allowed during business hours. See A‑board rules in § 1204. § 1204 (A‑board rules)

Are billboards (off‑site advertising signs) allowed in Isleton?

No. The zoning code expressly prohibits outdoor advertising structures of a permanent nature (billboards); Isleton favors on‑site identification and restricts off‑site advertising. § 1204.B.18; § 1204.D.18

What are the rules for signs in industrial zones?

Industrial sites may use either 1 sq ft per lineal foot of property line adjacent to a street or 100 sq ft per acre of site area (whichever is greater) up to a 600 sq ft cap; temporary non‑verbal signs (banners/flags) are limited to 10% of that maximum or 60 sq ft. § 1204.E.1–E.2

How long can temporary banners and campaign signs stay up?

Most temporary signs (campaign posters, event posters) must be removed within 7 days after the event or election; banners associated with civic events are allowed upon council approval and must be removed within 14 days after the event is completed, per § 1204.D.10–11. § 1204.D.10–11

What happens to older signs that don’t meet the current code?

Signs lawfully on a site when the ordinance took effect are treated as non‑conforming and may be maintained but are restricted from enlargement or relocation except as provided in the nonconforming rules; alterations have limits and full replacement may require compliance. See § 1308 (nonconforming signs). § 1308; § 1204.F

Do painted murals count against my sign area in a C district?

Yes — painted wall signs and murals that function as signage are included when computing allowable sign area in any C district. § 1204.D.8

If a sign obstructs sight lines at an intersection, what is allowed?

Signs are generally prohibited within 30 ft of an intersection (intersecting curb lines) unless the top is at most 2½ ft off the ground or the bottom is at least 10 ft above ground; this is to protect sight distance and safety. § 1204.B.16

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