Tuolumne County — Development Standards

Last reviewed: July 3, 2026

Overview

This page summarizes the development-standards rules that apply in the unincorporated areas of Tuolumne County under Title 17 (Zoning). It covers the code’s district-level limits on setbacks, height, lot coverage / FAR, density, and minimum parcel sizes, and points to where applicants must check overlays, design review, parking, and ADU rules. Primary controlling rules are in § 17.22.020, § 17.22.030, and the district chapters in Article 2 (e.g., § 17.12.020 for R‑1, § 17.14.020 for MU).

NOTE: these standards apply only to unincorporated areas of Tuolumne County; incorporated cities inside the county use their own codes. For the countywide context see the Tuolumne County zoning overview.

Key cross-cutting rules (how the code measures and applies standards)

• Height limits: the County groups zones into two default height bands: 40 ft and 50 ft (district list in § 17.22.020) — exceptions and appurtenances rules also appear in that section. § 17.22.020
• Setbacks: the base yard setbacks for most zones are 15 ft front, 15 ft rear, 6 ft side (with a separate 35‑ft centerline/streetside rule); exceptions for commercial/industrial adjacency and historic districts are in § 17.22.030. § 17.22.030
• Measurement: setbacks from adopted right‑of‑way centerlines are specifically required where a future ROW exists; nonconforming parcel rules allow limited reductions — see § 17.22.030 and related definitions. § 17.22.030
• Floor Area Ratio (FAR) and lot coverage: many districts express intensity as a maximum FAR (or percent coverage) and a maximum dwelling units/acre; these are set per district in the Article 2 district chapters (examples below). See district chapters (e.g., § 17.12.020, § 17.12.030, § 17.14.020).
• ADUs: the County’s accessory dwelling unit rules (development standards, height, setbacks, maximum sizes) are in the ADU chapter (Chapter 17.36) and include local limits consistent with state ADU law; applicants must also read state ADU rules. § 17.36
• Design review / Site Development Permits: many larger or commercial/residential projects require a Site Development Permit or Site Development/Design review — see the Site Development Permit applicability provisions (district list) and the County’s design review guidance.

Quick links you’ll want while reading:

• first mention of “parking” in this page links to the County parking page;
• first mention of “design review” above is linked to design review;
• first mention of “overlay” references the County overlay districts page;
• first mention of “historic” refers to historic preservation;
• the first time the page discusses ADUs I link to California’s ADU law;
• the first time building-code constraints are noted, I link to the California Building Standards Code.

(Those links are to county/topic pages used by GoCodebook for the unincorporated county context.)

District-by-district breakdown (selected districts — unincorporated Tuolumne County)

Note: the code contains additional districts and use tables (Table 17.xx). Always confirm a parcel’s actual zoning on the County zoning map and verify with staff for parcel-specific exceptions.

R-1 — Single‑Family Residential (§ 17.12.020)

• Purpose & typical uses: low‑density single‑family neighborhoods; accessory uses and ADUs allowed per Chapter 17.36. § 17.12.020
• Key dimensional standards: minimum parcel size 7,260 sq ft, maximum density 6 du/acre, maximum FAR 0.5 for parcels ≥7,260 sq ft (higher FAR allowed for smaller lots or multiple stories per the subsection). § 17.12.020
• Height & setbacks: base height band is 40 ft and base setbacks per § 17.22.030 (front 15 ft, rear 15 ft, side 6 ft), plus the 35‑ft centerline rule. § 17.22.020 § 17.22.030
• Where it applies: typical unincorporated residential subdivisions and neighborhood pockets; see Table 17.12.1 for permitted accessory and home‑business uses. § 17.12.020

R-2 — Medium‑Density Residential (§ 17.12.030)

• Purpose & uses: duplexes, townhomes, small multi‑unit buildings; accessory uses and family day care allowed. § 17.12.030
• Key dimensional standards: maximum density 12 du/acre, FAR 0.5 on parcels ≥7,500 sq ft (FAR 0.6–0.75 on smaller lots depending on stories). § 17.12.030
• Height: part of the 40 ft band unless otherwise specified (see § 17.22.020). § 17.22.020
• Permits: Site Development Permit often applies for building projects in R‑2. § 17.98 / Site Development Permit (applicability)

R-3 — Multiple‑Family Residential (§ 17.12.040)

• Purpose & uses: apartments, multi‑unit housing; multiple‑family use provisions (e.g., on‑site recreation) apply. § 17.12.040
• Key dimensional standards: maximum density 15 du/acre, FAR 0.5 for larger parcels (0.6–0.75 on small parcels depending on stories). § 17.12.040
• Height: belongs to the 50 ft band unless modified. § 17.22.020

RE‑1 / RE‑2 / RE‑3 / RE‑5 / RE‑10 — Residential Estate districts (Chapter 17.12, multiple sections)

• Purpose: low‑density country/estate living; public water/sewer not required in many RE zones. § 17.12 (residential estate sections)
• Key dimensional standards: minimum parcel sizes vary (e.g., RE‑1 = 1 acre, RE‑2 = 2 acres, RE‑3 = 3 acres, RE‑5 = 5 acres, RE‑10 = 10 acres), and dwelling intensity is typically one dwelling per the acreage (e.g., 1 per 2 acres in RE‑2). FAR in these districts is commonly 0.5 or otherwise stated in each RE section. § 17.12.050–17.12.090

A‑10 / A‑20 / AE‑37 — Agricultural Districts (Chapter 17.10)

• Purpose & uses: agricultural production, accessory farm structures; parcel minimums are large (e.g., A‑20 = 20 acres), and residential density limits are low (e.g., one dwelling per 10–20 acres). § 17.10
• FAR: typically 0.2 in agricultural districts where intensity is stated. § 17.10

O / O‑1 — Open Space (§ 17.10.070 / 17.10.080)

• Purpose: preserve open land; building intensity often not applicable and many structures are limited or prohibited. § 17.10.070–080

MU — Mixed‑Use (§ 17.14.020)

• Purpose & uses: mix of residential, commercial, and recreational in urban/community centers; expected to be served by public water and sewer. § 17.14.020
• Key dimensional standards: minimum parcel 2,500 sq ft / 50 ft width, maximum density 15 du/acre, minimum density 8 du/acre, maximum FAR 2.0. § 17.14.020
• Practical note: MU is intended for more intensive urban infill in unincorporated community centers; density bonuses (Chapter 17.26) can increase intensity for affordable housing. § 17.14.020, § 17.26

C‑O / C‑1 / C‑2 / C‑K / C‑S — Commercial districts (Chapter 17.14)

• Purposes:
  • C‑O (Neighborhood Commercial): small-scale retail/serving nearby residential areas. § 17.14.040
  • C‑1 (General Commercial): broader retail and services; FAR up to 2.0 in several commercial districts and densities up to 15 du/acre in mixed/residential conditions. § 17.14.050
  • C‑2 (Heavy Commercial): wholesale, larger commercial uses; FAR often 2.0; density rules differ. § 17.14.060
  • C‑K (Commercial Recreational): resort/vacation‑oriented development; FAR and density lower (example: FAR 0.5, 1 du per 2 acres for residential intensity in C‑K). § 17.14.030
• Setbacks and buffering rules apply where commercial districts abut residential districts (special setback rules in § 17.22.030). § 17.22.030
• Site Development Permits are commonly required for commercial projects; check Site Development Permit applicability. § 17.98 / Site Development Permit

M‑1 / M‑2 — Industrial districts (§ 17.16)

• Purpose & uses: light and heavy industrial uses; FAR and densities differ by district (e.g., M‑1 FAR 1.0, M‑2 FAR 1.0, residential intensity limited). § 17.16.030
• Height & setbacks: industrial districts are listed in the 50 ft height band unless a specific exception applies. § 17.22.020

Quick standards table (decision‑relevant at intake)

Practical guidance / interpretation notes

• The County sets a baseline (setbacks, heights, FAR, densities) and then applies district-level exceptions and combining districts (e.g., airport compatibility, historic combining zones) that can tighten or change those standards — always check the parcel’s combining districts and overlays in addition to the base zone. § 17.20 (Combining Districts) and related overlay chapters.
• Where a project proposes to exceed a district limit (height, setback), the code provides mechanisms — use permits, minor modifications, or density bonus/incentive processes — but some standards (lot area, maximum FAR, residential density) are specifically excluded from minor modifications. See the Minor Modification and Use Permit sections. § 17.96 (Minor Modifications) and § 17.26 (Density Bonus).
• For mixed‑use and multi‑family projects expect Site Development Permit review and possible design review; check the Site Development Permit applicability list. (Site Development Permit applicability)
• ADUs: local ADU standards are in Chapter 17.36 but state ADU law can preempt local rules in several areas (size, setbacks, parking). Link to the state ADU rules for conflicts. Ch. 17.36
• Fire and defensible‑space requirements can impose additional setback/clearance and access requirements (Tuolumne County Fire Code and Chapter 15.20; Public Resources Code § 4290 referenced in small‑lot standards). Verify with the County Fire Marshal.

Checklist — what an applicant must satisfy at intake

• Confirm parcel is in unincorporated Tuolumne County and obtain current zoning and combining districts from County maps (verify overlays). § 17.08 / 17.20
• Confirm permitted uses vs. conditional uses in the zone (see Table 17.xx for that district). Article 2 district tables
• Show compliance with setbacks (15/15/6 baseline or district‑specific) and 35‑ft centerline rule; dimension building footprints and show FAR. § 17.22.030
• Demonstrate the project meets the height limit for the zone (40 ft or 50 ft) or include a use‑permit request for height increase. § 17.22.020
• Document lot coverage / FAR, dwelling units per acre, and minimum parcel size compliance. (District chapters: e.g., § 17.12.020, § 17.14.020).
• Show off‑street parking compliance or provide justification for reductions (see Chapter 17.30). § 17.30
• If in a commercial/industrial/multi‑family/MU district, prepare for a Site Development Permit submittal and objective site/design standards. (Site Development Permit applicability)
• If proposing an ADU, follow Chapter 17.36 and check state ADU law limits (setbacks, size, parking). Ch. 17.36
• If any overlay applies (airport, historic, TPZ/forest, flood), include overlay‑specific materials and studies. § 17.20 / airport ALUC rules Ch. 18.28.

Risks & Ambiguities

Plain‑English summary

In unincorporated Tuolumne County, Title 17 sets baseline development rules: most residential zones use 15 ft front / 15 ft rear / 6 ft side setbacks and 40 ft height limits, while commercial/multi‑family/industrial zones are normally in a 50 ft height band; intensity is controlled by dwelling units per acre and FAR that vary by zone (see the district chapters and the general rules in § 17.22.020–030). Always check the parcel’s zone, overlays, and the County’s Site Development Permit and ADU chapters — and verify uncertain, parcel‑specific questions with County planning staff.

Source References

• Tuolumne County Zoning Code (Title 17), Standards for All Development and Uses — § 17.22.020 (Height Regulations) and § 17.22.030 (Parcel, Yard, and Space Regulations).
• Tuolumne County Zoning Code, Residential Districts — § 17.12.020 (R‑1), § 17.12.030 (R‑2), § 17.12.040 (R‑3).
• Tuolumne County Zoning Code, Commercial & Mixed‑Use Districts — § 17.14.020 (MU), § 17.14.030 (C‑K), other C districts.
• Tuolumne County Zoning Code, Industrial Districts (Chapter 17.16) and allowed FAR/density tables.
• Tuolumne County Zoning Code, ADU chapter and accessory‑use standards — Chapter 17.36 (local ADU development standards).
• Density bonus and affordable‑housing incentives — Chapter 17.26.
• Site Development Permit applicability and procedures (Site Development Permit discussion and applicability list).
• Small‑lot subdivision standards (development standards exceptions and references to Titles 15 and 16 for setbacks and fire requirements).

Retrieved passages

• Tuolumne County Zoning Code High relevance show source text
• Tuolumne County Zoning Code High relevance show source text
• Tuolumne County Zoning Code High relevance show source text
• CFC § 4290 (article shall) High relevance show source text
• Tuolumne County Zoning Code High relevance show source text
• Tuolumne County Zoning Code (Title to) High relevance show source text
• Tuolumne County Zoning Code High relevance show source text
• Tuolumne County Zoning Code (Section 17.100.090.B) High relevance show source text
• Tuolumne County Zoning Code (Section 65915.5) High relevance show source text
• Tuolumne County Zoning Code (Title 15) Medium relevance show source text
• CBC § 130 (ARTICLE 3) Medium relevance show source text
• Tuolumne County Zoning Code (§ 4) Medium relevance show source text
• Tuolumne County Zoning Code (Title 15) Medium relevance show source text
• Tuolumne County Zoning Code (Chapter 1.10) Medium relevance show source text
• Tuolumne County Zoning Code (Title or) Medium relevance show source text

Cited sections

• Tuolumne County Zoning Code (Title 17), Standards for All Development and Uses — **§ 17.22.020** (Height Regulations) and **§ 17.22.030** (Parcel, Yard, and Space Regulations). (Title 17)
• Tuolumne County Zoning Code, Residential Districts — **§ 17.12.020** (R‑1), **§ 17.12.030** (R‑2), **§ 17.12.040** (R‑3). (§ 17.12.020)
• Tuolumne County Zoning Code, Commercial & Mixed‑Use Districts — **§ 17.14.020** (MU), **§ 17.14.030** (C‑K), other C districts. (§ 17.14.020)
• Tuolumne County Zoning Code, Industrial Districts (Chapter 17.16) and allowed FAR/density tables. (Chapter 17.16)
• Tuolumne County Zoning Code, ADU chapter and accessory‑use standards — **Chapter 17.36** (local ADU development standards). (chapter and)
• Density bonus and affordable‑housing incentives — **Chapter 17.26**. (Chapter 17.26)
• Site Development Permit applicability and procedures (Site Development Permit discussion and applicability list).
• Small‑lot subdivision standards (development standards exceptions and references to Titles 15 and 16 for setbacks and fire requirements).
• TuolumneCounty_ZoningCode.md