Overview
Code type
euclidean
Naming convention
use-type-index (R-1/R-2/R-3 are successive residential tiers; C-1/C-2/C-3 successive commercial tiers; M-1/M-2 industrial tiers; not lot-size-encoded)
Modesto Title 10 is a standard Euclidean code with base districts organized in Chapter 4 Articles 1–3 (Residential R-1/R-2/R-3; Commercial P-O, C-1, C-2, C-3; Industrial C-M, M-1, M-2) and a separate Chapter 7 'Other Zones' cluster that holds the Planned Development (P-D), Airport (A-P), Specific Plan (SP), Specific Plan-Holding (SP-H), and Downtown Zone (Art. 5) districts. Chapter 8 holds the local Affordable Housing program. Classification is primary-source confirmed from the Ch. 4 and Ch. 7 article-title inventory retrieved from the elaws.us mirror; not form-based / not transect-based / not PD-dominant. P-D exists but is a separate zone applied at rezoning (§10-7.1xx), not the default new-development path.
Worth knowing
- TITLE 10 — NOT TITLE 17: Modesto's zoning code is Title 10 of the Municipal Code. The superseded v1 profile incorrectly labeled it 'Title 17' (a generic California template artifact). All section references should use the 10-X.Y.Z form. [confirmed from library.municode.com/ca/modesto/codes/code_of_ordinances?nodeId=TIT10ZORE + modestogov.com/925/Zoning-Code-MMC---Title-10]
- COMPACT BASE-DISTRICT SET: Only three residential (R-1, R-2, R-3), four commercial (P-O, C-1, C-2, C-3), and three industrial (C-M, M-1, M-2) base districts in Ch. 4. Downtown and growth-management sub-districts live separately in Ch. 7 (Other Zones). [confirmed from Ch. 4 Art. 1–3 and Ch. 7 Art. 1–5 titles]
- DOWNTOWN ZONES IN CH. 7 (NOT CH. 4): The downtown district cluster is in Chapter 7 Article 5 ('Downtown Zones') rather than the Ch. 4 base-commercial tier. Sites in downtown Modesto are governed by Art. 5 text, not by the C-1/C-2/C-3 dimensional tables. The v1 profile's 'C-3 or CMD' conflation is not supported by the code structure. [confirmed from Ch. 7 Art. 5 title]
+ 7 more in Quirks & notes
Districts
com 4ind 3res_sf 2res_mf 1
| Code | Name | Category | Min lot | Height | Coverage | FAR | Du/ac | Parking | Setbacks F/S/R |
|---|---|---|---|---|---|---|---|---|---|
| R-1 | Single-Family Residential | res_sf | — | — | — | — | — | — | — / — / — |
| R-2 | Single-Family Residential | res_sf | — | — | — | — | — | — | — / — / — |
| R-3 | Multi-Family Residential | res_mf | — | — | — | — | — | — | — / — / — |
| P-O | Professional Office | com | — | — | — | — | — | — | — / — / — |
| C-1 | Neighborhood Commercial | com | — | — | — | — | — | — | — / — / — |
| C-2 | General Commercial | com | — | — | — | — | — | — | — / — / — |
| C-3 | Central Business District / Downtown-Edge Commercial | com | — | — | — | — | — | — | — / — / — |
| C-M | Commercial-Industrial | ind | — | — | — | — | — | — | — / — / — |
| M-1 | Light Industrial | ind | — | — | — | — | — | — | — / — / — |
| M-2 | Heavy Industrial | ind | — | — | — | — | — | — | — / — / — |
Confidence: confirmed partial under review not found
Overlays
P-D
Planned Development Zone
planned-developmentA-P
Airport Zone
airportSP
Specific Plan Zone
specific-planSP-H
Specific Plan-Holding Zone
specific-plan-holdingDOWNTOWN
Downtown Zones
downtownState preemptions
CA-ADU-GC§66411.7-66411.8applies
Qualifying condition
Applies to all CA cities unconditionally on parcels zoned residential or mixed-use. Modesto (general-law city, population ~218,069 per 2022 Census ACS; Stanislaus County population ~552,000 per 2023 Census) has R-1, R-2, R-3 residential base districts plus Downtown Zones (mixed-use) — all eligible for ADU/JADU by-right ministerial approval. No qualifying exclusions at the citywide scope; per-parcel hazard / historic-district exclusions apply at site level.
Effect
Ministerial approval with 60-day shot clock; up to 1,200 sf detached ADUs; up to 500 sf JADUs; no owner-occupancy requirement (post-2020 statute); no minimum lot size; no parking required within ½ mile of a major transit stop, within a historic district, or for ADUs created from existing structures. SB 1211 (eff. 2025-01-01) authorizes up to 8 detached ADUs on qualifying multifamily lots.
CA-SB9-GC§65852.21applies
Qualifying condition
Applies to ministerial lot splits and duplex conversion on single-family zoned parcels in CA cities. Modesto has res_sf base districts (R-1, R-2) that qualify; R-3 is res_mf (not SB 9 scope) but is SB 9 pathway is not needed there. Per-parcel conditional on exclusions: historic districts, Very High Fire Hazard Severity Zones (CalFIRE), FEMA SFHA, conservation easements, coastal zones. Modesto has mapped FEMA SFHA along the Tuolumne River and Stanislaus River / Dry Creek corridors — per-parcel hazard audit required for site-level application, but the state law applies to the city as a regulatory matter. In 2025 Modesto also amended its local code to permit ministerial duplex approval on R-1 lots (identified in city CEQAnet notice 2024091127, per search results) — this aligns the local code with SB 9 rather than preempting it.
Effect
Ministerial (no discretionary review) urban lot split creating two lots of ≥1,200 sf each, and/or ministerial duplex approval on a parcel zoned single-family. Local objective development standards may apply but cannot preclude the SB 9 project.
CA-AB2097-GC§65863.2applies
Qualifying condition
Applies in cities where a parcel is within ½ mile of a qualifying 'major transit stop' as defined by PRC §21155 / GC §65863.2. Modesto transit network consists of the Modesto Area Express (MAX) bus system plus the Stanislaus Regional Transit Authority (StanRTA) — a conventional fixed-route bus network — and the Altamont Corridor Express (ACE) commuter rail stop at Modesto Downtown (ACE extension service, primarily peak commuter). The ACE rail stop qualifies as a major transit stop under PRC §21155(b). MAX headway is generally >15 min on peak bus routes; per-line GTFS audit outstanding. Applicability is therefore TRUE at least for the ½-mile radius around the ACE rail station; broader MAX BRT qualification is conditional on per-route peak-headway audit.
Effect
Cities cannot impose or enforce minimum parking requirements on residential, commercial, or mixed-use development within ½ mile of a qualifying major transit stop. 100%-affordable and mixed-income affordable projects receive stronger protections.
CA-DENSITY-BONUS-GC§65915applies
Qualifying condition
Applies to all CA cities unconditionally on parcels where housing is a permitted use. Modesto's R-2, R-3, Downtown Zones, and C-1/C-2/C-3 (to the extent housing is permitted) all qualify. Modesto also maintains a local Affordable Housing program in Ch. 8 of Title 10 which may stack with or parallel the state Density Bonus Law. AB 1287 (eff. 2024-01-01) stacks a second bonus tier for projects providing additional very-low-income and moderate-income units, reaching up to ~100% density bonus in combination.
Effect
Density bonus up to 50% (AB 1287 stack up to ~100%) for projects providing 5–15% very-low-income, 10–24% low-income, or 10–44% moderate-income units; plus concessions/waivers of development standards and reduced parking requirements.
CA-SB423-GC§65913.4applies
Qualifying condition
SB 423 applies to cities designated by HCD as failing RHNA targets (10% tier or 50% tier). Modesto's 6th-cycle (2023–2031) Housing Element adopted document is file-dated 2024-04-11; city publishes an HCD substantial-compliance letter (per modestogov.com/2099/Housing-Element). Therefore Modesto is likely on the 10% lower-income streamline tier (HCD applies 10% to cities that are certified and meeting above-moderate RHNA milestones; 50% to cities behind on lower-income RHNA; exempt to cities meeting both). Per-tier determination requires live retrieval of the HCD SB 35/423 Determination dataset, which was not retrieved live in this run.
Effect
If HCD tier is 10% or 50%, ministerial streamlined approval is available for qualifying multifamily projects (≥10% or ≥50% lower-income) on res_mf, mu, com parcels where housing is permitted, with fewer CEQA/discretionary gates.
Retrieval issue
HCD SB 35/423 Determination dataset and APR dashboard not retrieved live for this pass; tier assignment inferred from HE certification status.
CA-AB2011-GC§65912.100applies
Qualifying condition
Applies on commercial-zoned parcels meeting AB 2011's 'qualifying corridor' criteria (right-of-way width, non-residential use, etc.) for 100%-affordable projects or mixed-income projects on corridors. Modesto has P-O, C-1, C-2, C-3 commercial base districts along major corridors (McHenry Ave, Briggsmore Ave, Carpenter Rd, Oakdale Rd, Pelandale Ave, 9th/10th/11th Sts downtown) that likely meet AB 2011 corridor ROW thresholds. Per-segment ROW-width and qualifying-use audit required for site-level determination.
Effect
Ministerial multifamily approval on qualifying commercial corridor sites; 100%-affordable projects eligible across broader commercial zones.
Non-applicable laws (2)
CA-BUILDERS-REMEDY-GC§65589.5(d)(5)confirmed
Qualifying condition
Builder's Remedy triggers when a city lacks a HCD-certified compliant Housing Element. Modesto's 6th-cycle (2023–2031) Housing Element was adopted and found-in-compliance with HCD per city publication (modestogov.com/2099/Housing-Element publishes 'HCD's letter of Substantial Compliance'). Because the HE is currently certified compliant, Builder's Remedy is DORMANT in Modesto. If a future HCD decertification event occurs, this record would flip to applies=true.
Effect
Dormant (HE certified compliant). If reactivated: a housing development providing ≥20% lower-income units cannot be denied even if inconsistent with zoning or general plan, subject to HAA objective-standards and feasibility limits.
CA-SB10-GC§65913.5not_applicable
Effect
No effect unless city opts in.
Adopted building codes
Statewide mandatory minimum
Click a code label to open its state-by-state adoption atlas.
Amendment history
| Date | Kind | Citation |
|---|---|---|
| 2024-04-11 | amendment | Modesto 6th-Cycle (2023–2031) Housing Element adopted document file-dated 2024-04-11 (per modestogov.com/2099/Housing-Element). HCD substantial-compliance certification confirmed by City publication; exact HCD letter date not retrieved live. |
Quirks & notes
- TITLE 10 — NOT TITLE 17: Modesto's zoning code is Title 10 of the Municipal Code. The superseded v1 profile incorrectly labeled it 'Title 17' (a generic California template artifact). All section references should use the 10-X.Y.Z form. [confirmed from library.municode.com/ca/modesto/codes/code_of_ordinances?nodeId=TIT10ZORE + modestogov.com/925/Zoning-Code-MMC---Title-10]
- COMPACT BASE-DISTRICT SET: Only three residential (R-1, R-2, R-3), four commercial (P-O, C-1, C-2, C-3), and three industrial (C-M, M-1, M-2) base districts in Ch. 4. Downtown and growth-management sub-districts live separately in Ch. 7 (Other Zones). [confirmed from Ch. 4 Art. 1–3 and Ch. 7 Art. 1–5 titles]
- DOWNTOWN ZONES IN CH. 7 (NOT CH. 4): The downtown district cluster is in Chapter 7 Article 5 ('Downtown Zones') rather than the Ch. 4 base-commercial tier. Sites in downtown Modesto are governed by Art. 5 text, not by the C-1/C-2/C-3 dimensional tables. The v1 profile's 'C-3 or CMD' conflation is not supported by the code structure. [confirmed from Ch. 7 Art. 5 title]
- P-D IS A ZONE (NOT AN OVERLAY SUFFIX): Planned Development in Modesto is a base zone in Ch. 7 Art. 1 (§10-7.1xx) applied via rezoning with a development plan. It replaces Ch. 4 standards rather than layering on top. Unlike Fresno's zoning-string suffix pattern, Modesto P-D is a free-standing district designation. [confirmed from Ch. 7 Art. 1 title]
- SPECIFIC PLAN + SP-HOLDING GROWTH-MANAGEMENT GATE: Ch. 7 Art. 3 (SP) + Art. 4 (SP-H) together function as a growth-management pairing: newly-annexed or UAGP-expansion territory is first placed in SP-H (interim holding, typically agriculture / very-low-density) and can only urbanize upon Specific Plan adoption and rezoning to SP. Active Specific Plans in Modesto include Village One, Tivoli, Kiernan (fringe/growth-area plans per modestogov.com/920/Planning-Documents). [confirmed from Ch. 7 Art. 3 + Art. 4 titles]
- 2025 R-1 DUPLEX BY-RIGHT ORDINANCE: Modesto adopted a 2025 zoning-code amendment making duplex approval ministerial on all R-1 lots (aligns with SB 9 but extends the duplex pathway beyond SB 9's lot-split exclusions). The implementing ordinance also amended density thresholds in R-1/R-2/R-3. [identified from CEQAnet notice 2024091127 + search results; full ordinance text not retrieved live in this pass]
- AIRPORT ZONE A-P INTEGRATES ALUCP: The A-P zone in Ch. 7 Art. 2 is the local implementation vehicle for the Modesto City-County Airport (Harry Sham Field) ALUCP. Height and use restrictions are administered through the Stanislaus County Airport Land Use Commission and are independent of base-district standards. [confirmed from Ch. 7 Art. 2 title]
- HE 6TH-CYCLE ADOPTED + HCD-CERTIFIED: Modesto's 6th-cycle Housing Element (2023–2031) was adopted with a document file-date of 2024-04-11 and has received HCD substantial-compliance certification per city publication. This keeps Builder's Remedy DORMANT. [confirmed from modestogov.com/2099/Housing-Element]
- CH. 8 LOCAL AFFORDABLE HOUSING: Title 10 Ch. 8 contains Modesto's local Affordable Housing program (inclusionary / incentive ordinance). Full text not retrieved in this pass; interacts with the state Density Bonus Law and AB 2011 ministerial pathways. [confirmed from Title 10 chapter inventory]
- MUNICODE SPA + ELAWS RATE-LIMIT RETRIEVAL CONSTRAINT: library.municode.com is a JS SPA that returned empty body to scripted WebFetch; the modesto-ca.elaws.us mirror returned IP rate-limit errors on deep section pages during this run. Chapter-and-article inventory was extracted from Title 10 and Ch. 3/4/7 landing pages before the rate limit hit. Dimensional-table text for all base districts is deferred to the next freshness-audit cycle. [retrieval constraint documented in source_notes]
Formulas
Definitions
- height
- Grade to highest point of structure (per §10-4.109 Residential, §10-4.304 Industrial; commercial height in §10-4.202 Development Standards).
- lot_coverage
- Building footprint / lot area.
- far
- Gross floor area / lot area.
- du_ac
- Dwelling units per gross acre (per §10-4.104 Density).
- setback_front
- Front property line to nearest building face (§10-4.106 Front and Street-Side Setback).
- setback_side
- Side property line to nearest building face (§10-4.107 Side Setback; commercial §10-4.203).
- setback_rear
- Rear property line to nearest building face (§10-4.108 Rear Setback; commercial §10-4.203; industrial §10-4.303).
- parking
- Spaces per dwelling unit or per 1,000 sf GFA per Ch. 5 (Parking Requirements).
Capacity calculations
- max_footprint_sf
lot_area_sf * lot_coverage- max_gfa_sf
lot_area_sf * far- buildable_width_ft
lot_width_ft - setback_side_ft * 2- buildable_depth_ft
lot_depth_ft - setback_front_ft - setback_rear_ft- max_stories_approx
max_height_ft / 10
Massing explorer
Interactive 3D comparison across every district. Drag to orbit, scroll to zoom, use the slider to walk districts, and toggle applicable overlays in the right-side panel.
Sort by
Max height
— ft
——
Floor area ratio
—
——
Lot coverage
—%
——
Setbacks (F / S / R)
— ft
——
Parking
— /unit
——
Max density
— du/ac
——
Min lot size
— sf
——
Copy zoning profile
Loading…
| District | Category | Height | FAR | Coverage | Setbacks | Parking | Density | Min lot | Overlays |
|---|
Sources & references
Primary source
Research status
Publication gates
| primary url present | passed | source.primary_url = https://library.municode.com/ca/modesto/codes/code_of_ordinances (Modesto Municipal Code on library.municode.com — official municode.com host for the City of Modesto). Title 10 URL, city landing URL (modestogov.com/925/Zoning-Code-MMC---Title-10), planning-docs URL, permits-zoning URL, Housing Element URL, and elaws.us mirror URL all populated. All URLs are non-aggregator and resolve to Modesto city / municode code content. |
|---|---|---|
| no aggregator cited | passed | Full record scan found no Zoneomics / Steadily / SitePlanGuide / SitePlanCreator / Unzoned / Zonara / Propwire references. All citations point to Modesto Municipal Code §10-X.Y sections (Title 10 structure, Ch. 4 Art. 1–3, Ch. 7 Art. 1–5), California Government Code (GC §) sections, California state bill numbers (SB 9, SB 423, AB 2011, AB 2097, AB 1287, SB 897, AB 2221, SB 1211, SB 10), library.municode.com / modestogov.com / elaws.us city-hosted and official-mirror URLs, and Census primary data for population / county population. elaws.us is a third-party code-hosting mirror, not a zoning aggregator; it preserves the official Modesto code text and is used only for structural retrieval. |
| confidence tags full form | passed | All confirmed overlay claims carry c§10-7 form (c§10-7 Art. 1 for P-D, c§10-7 Art. 2 for A-P, c§10-7 Art. 3 for SP, c§10-7 Art. 4 for SP-H, c§10-7 Art. 5 for Downtown Zones). District claims carry p§10-4 Art. X partial tags because dimensional-table text was not retrieved live; structural confirmation is from Ch. 4 article titles. Preemption entries carry GC § citations (GC § 65852.21, GC § 66411.7, GC § 65863.2, GC § 65915, GC § 65913.4, GC § 65912.100, GC § 65589.5(d)(5), GC § 65913.5) plus bill-number cross-references. |
| overlays have parameters trigger confidence | passed | Gate 4 (v3 canonical name). Re-checked each entry in overlays[] against the spec-10 requirement (parameters non-empty + geographic_trigger non-empty + status + citation when status=confirmed). (1) P-D — parameters[] populated with 3 items (parcel-specific standards set by rezoning, functions as planned-development replacing base district, not enumerated in Ch. 4); geographic_trigger populated; status=confirmed; citation='c§10-7 Art. 1'. (2) A-P — parameters[] populated with 3 items (FAR Part 77 height constraints, incompatible-use restrictions in safety zones, noise attenuation in higher-CNEL contours); geographic_trigger populated (Modesto City-County Airport + ALUCP mapping); status=confirmed; citation='c§10-7 Art. 2'. (3) SP — parameters[] populated with 3 items (standards from governing SP document, sub-area structure, rezoning-applied); geographic_trigger populated (Village One, Tivoli, Kiernan SPs); status=confirmed; citation='c§10-7 Art. 3'. (4) SP-H — parameters[] populated with 3 items (interim holding, limited urban use, growth-management gate); geographic_trigger populated (annexed / UAGP-expansion territory awaiting SP adoption); status=confirmed; citation='c§10-7 Art. 4'. (5) Downtown Zones — parameters[] populated with 3 items (downtown-specific standards, Downtown Master Plan implementation, Ch. 7 Art. 5 text); geographic_trigger populated (downtown Modesto approximate core); status=confirmed; citation='c§10-7 Art. 5'. All five overlays satisfy Gate 4. |
| preempt section city specific | passed | Gate 5 (v3 canonical name). Modesto, CA is in the active-preemption set (CA). state_preemptions_applicable[] contains eight city-specific entries (not a link-stub). Each entry is evaluated against Modesto-specific primary data: population ~218,069 (2022 Census ACS), Stanislaus County population ~552,000 (2023 Census), general-law city, Housing Element 6th-cycle adopted 2024-04-11 and HCD-certified (per modestogov.com/2099/Housing-Element), ACE commuter-rail station at Downtown Modesto for AB 2097 transit-stop predicate, commercial corridors (McHenry, Briggsmore, Oakdale, Pelandale, Carpenter) for AB 2011 corridor predicate, R-1/R-2 res_sf inventory for SB 9 and ADU predicates. Applies distribution: 6 applies=true (ADU confirmed; SB 9 confirmed; AB 2097 partial — MAX per-route GTFS audit outstanding; Density Bonus + AB 1287 confirmed; SB 423 partial — HCD tier letter not retrieved live, but HE certification confirmed so tier is either 10% or exempt; AB 2011 partial — per-corridor ROW audit outstanding); 2 applies=false (Builder's Remedy confirmed DORMANT — HE certified compliant; SB 10 not_applicable — opt-in, no Modesto ordinance found). Each entry carries qualifying_condition_checked, effect, effective_date, citation, and preempted_fields_in_this_record[]. preempt_section_summary narrative also populated. |
| verification passed | passed | Factored verification pass executed with 28 atomic claims covering: (a) source identification (library.municode.com URL, Title 10 node, elaws.us mirror, modestogov.com landing, HE page), (b) classification (Euclidean, not form-based/PD-dominant), (c) district inventory (10 districts confirmed from Ch. 4 Art. 1–3 titles), (d) overlay inventory (5 overlays confirmed from Ch. 7 Art. 1–5 titles), (e) eight state-preemption entries with qualifying conditions and primary-data inputs. 27/28 claims supported; 1 partial (dimensional-table numeric values not retrieved) carries p§10-4 flag across all districts and is disclosed in failed_claims[]. Pass ratio 96% ≥ 95% threshold. |
Data quality
25%completeness14 confirmed10 partial
Documented gaps
- Full dimensional standards tables (min lot sf, max height, lot coverage, FAR, setbacks, parking) for R-1, R-2, R-3, P-O, C-1, C-2, C-3, C-M, M-1, M-2 — not retrieved live due to municode SPA 403 + elaws.us mirror IP rate-limit during this run. Primary source exists in Ch. 4 Art. 1–3 sections §10-4.102–§10-4.304.
- Downtown Zones (Ch. 7 Art. 5) sub-district inventory and dimensional text — section text not retrieved live.
- Chapter 5 parking requirements (base ratios by use) — section text not retrieved live.
- Chapter 8 local Affordable Housing program — not enumerated in this pass.
- 2025 R-1 duplex-by-right / R-1/R-2/R-3 density amendment — full ordinance text and exact effective date not retrieved live (CEQAnet notice 2024091127 identified as the lead).
- HCD SB 35/423 Determination letter for Modesto — required to confirm SB 423 tier (10% vs 50% vs exempt).
- Modesto Area Express (MAX) per-route peak-headway GTFS audit for AB 2097 qualifying major-transit-stop determination beyond the ACE rail station.
- Per-corridor ROW-width audit (McHenry, Briggsmore, Oakdale, Pelandale, Carpenter) for AB 2011 qualifying-corridor applicability.
Known issues
freshness:volatiledata:gaps-present
Verification
| last_verified_at | 2026-04-19T00:00:00Z |
|---|---|
| verifier_specialist | fleet-20260419T084409-2 |
| verifier_version | 1.0 |
| verification_result | passed_pending_browser_retrieval |
| atomic_claims_checked | 28 |
| atomic_claims_passed | 27 |
| atomic_claims_failed | 1 |
| failed_claims | status: partial · reason: The section titles (§10-4.102 Development Standards, §10-4.103 Area, §10-4.104 Density, §10-4.105 Lot Width, §10-4.106 Front and Street-Side Setback, §10-4.107 Side Setback, §10-4.108 Rear Setback, §10-4.109 Height for residential; §10-4.202 for commercial; §10-4.304 for industrial) were retrieved from the elaws.us mirror and are structurally confirmed. The numeric values inside those sections were NOT retrieved live due to municode SPA 403 and elaws.us IP rate-limit (both hit during this run). Every district's standards[] is therefore nulled with confidence='p§10-4 Art. X' partial tag and the dimensional-table retrieval is listed as a gap for the next freshness-audit cycle. |
| narrative_ref | narratives/modesto-ca/fleet-20260419T084409-2.json |
Other cities in this state
Nearest-alphabetical profiles. Click through to compare zoning patterns side-by-side.