Local zoning · Merced County

Merced County — Design Review

Q: Who decides my design review—staff or the Planning Commission?

Most items are decided by the Director ; the Commission hears appeals and elevated cases. If your project is bundled with another permit (e.g., Conditional Use Permit), the higher Review Authority will decide both.

Q: Will parking, landscaping, and signage be reviewed as part of design review?

Yes. The standards in Chapters 18.38 (Off‑Street Parking), 18.36 (Landscaping), and 18.44 (Signs) are applied during design review to ensure integrated site design.

Design Review under the Merced County local zoning and planning code, with the controlling citations.

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Last reviewed: July 6, 2026

Overview

In unincorporated areas of Merced County, “Site Plan and Design Review” is the County’s formal design review process under Title 18 of the Zoning Code. It evaluates new development and exterior changes for design quality and consistency with County standards and plans, and it applies across zones when specific triggers are met, with review authority assigned by project type and scale in Table 6-3. See the County’s zoning framework and how it implements the General Plan on the Merced County zoning & planning overview and Merced County Zoning pages.

Plain-English anchor: If your project in the unincorporated areas adds three or more homes, builds a new nonresidential structure, touches a “sensitive site,” or makes substantial exterior changes visible from the street, expect design review unless a listed exemption applies.

When Design Review Is Required in Unincorporated Areas

Design review is codified as Site Plan and Design Review in Chapter 18.122. The County’s stated purpose is to ensure orderly development that fits its surroundings and County plans.

Core triggers—A Design Review Permit is required for:
- Three or more new residential units, or any new residential unit on a sensitive site; single-family homes are otherwise exempt unless on a sensitive site.
- New nonresidential buildings or site improvements deemed “significant,” and additions/exterior changes to nonresidential buildings visible from a public right-of-way when “significant.”
- Relocation of buildings/structures, certain grading (more than 50 cubic yards on slopes >10%), County projects (public buildings, parks, right‑of‑way landscaping, street furniture), and other projects the Director determines may adversely affect the environment or adjacent development.
“Significant projects”—Determination factors include the project’s visual prominence, height/mass/disturbance, context, and potential impacts; the Director’s call can be appealed to the Commission.
“Sensitive sites”—Include hillsides/ridgelines, mapped riparian or critical habitat areas, slopes >10%, within 200 ft of a lake or 50 ft of a stream, and sites with listed or potentially significant cultural/historic resources. The Director may require design review at these locations; this determination is appealable.
Exemptions—Examples include: building additions under 500 sq ft not visible from the public right-of-way, exterior modifications not visible from the public right‑of‑way, minor parking lot work that maintains required spaces, like-for-like doors/windows/roofing, similar-quality repainting/retexturing, small landscape tweaks, fence/wall replacements, code-compliance accessibility work, qualifying murals, and other Director‑determined minor/incidental work.

Design review may also be required when a “by-right” use involves construction in several zone chapters (Agricultural, Residential, Commercial, Industrial), which flag that the construction element may trigger Zoning Clearance or Site Plan and Design Review. See each zone’s “Permit Requirement Where Construction is Involved.”

Public Notice, Hearing, Appeals

Director-level decisions receive mailed notice; hearings occur only if requested. Referrals to Commission/Board require noticed public hearings. Appeals follow Chapter 18.144.
If paired with other discretionary permits, the higher Review Authority decides the design review concurrently.

Review Authority and How Decisions Are Made

The County assigns review by project category (Table 6‑3). The Director is the typical decision-maker; the Planning Commission hears appeals and elevated cases; the Board of Supervisors may be the final authority when legislative actions are involved.

Findings—To approve, the Review Authority must find the proposal: consistent with County plans and code, compatible with surroundings, uses compatible materials/colors/details, organizes site/circulation well, enhances shade/daylight/ventilation/water use, fits the parcel’s constraints, meets the standards of review, and protects health/safety/welfare.
Standards of Review—Compatibility, height/bulk/scale, privacy/views, architectural style and articulation, rooflines, screening of roof equipment, coordinated site features (driveways, parking, lighting, loading, signs, solar), pedestrian amenities, and CPTED principles. See also Landscaping and Sign chapters referenced by the standards.

Table: Selected design-review items and who decides

Item	Typical Review Authority	Notes	Code Reference
1–2 story single- or two‑family homes	Director (appealable to Commission)	Exempt if not on a sensitive site	§ 18.122.030 Table 6‑3 ; § 18.122.020
Multi-family new construction	Director (appealable)	Streamlined path available if eligible; see objective standards	§ 18.122.030 Table 6‑3 ; § 18.122.100
Nonresidential new buildings	Director (appealable)	If “significant,” design review is required	§ 18.122.020; § 18.122.030
Façade/exterior changes (incl. color)	Director (appealable)	Exempt if not visible from right‑of‑way	§ 18.122.030 Table 6‑3; § 18.122.020(D)
Joint/off-site parking plans	Director (appealable)	Must meet off‑street parking standards	§ 18.122.030 Table 6‑3; Ch. 18.38
Signs and sign programs	Director (appealable)	Must meet the Sign Regulations chapter	§ 18.122.030 Table 6‑3; Ch. 18.44

What Reviewers Look For (Standards of Review)

Compatibility with adjacent context; avoid visual domination; protect privacy and key views.
Strong architectural articulation; avoid long blank walls; coherent style; appropriate color palette; screen rooftop equipment.
Site orderliness and safety for pedestrians, cyclists, and vehicles; integrate amenities; align with objective development standards in applicable zone chapters. See Merced County Development Standards.
Integrate required standards for parking, landscaping and screening, and signage cited by the design review criteria.

Process notes: Applications are filed per Chapter 18.112, may be combined with other land-use approvals, may include an on‑site inspection, and carry permit time limits, expirations, and potential extensions (typically 12 months to commence; up to three 12‑month extensions). Modifications and post‑decision procedures are provided in Article 7.

Streamlined, Ministerial Objective Design Standards (Multi-Family)

For multi-family projects eligible under Government Code 65913.4, the County applies objective design standards, including tailored standards for the R‑2 zone and site/architectural expectations for R‑3 and R‑4. Examples: articulated façades with defined base/middle/top, permitted material palettes (wood, cement-based stucco, stone, brick, hardi-type siding; no vinyl or synthetic stucco), minimum two stories in some contexts, screened roof equipment, and pedestrian connectivity. These are in addition to applicable zone development standards.

R‑2 objective standards: architectural detailing and materials; duplex/townhouse compatibility; reinforced neighborhood character.
R‑3/R‑4 objective site/architectural standards: multi-story form, ground-floor ceiling heights, street-facing entries and semi-public attachments, screened mechanicals, pedestrian access to amenities.

District-by-District: Where Design Review Most Often Comes Up

Design review applies countywide based on the triggers above; this section flags typical issues and key dimensional baselines by district so applicants can anticipate fit and context. Always confirm parcel-specific overlays in Merced County Overlay Districts. “Not found in retrieved materials” indicates unavailable detail.

A-1 (General Agricultural)

Purpose/uses: Agricultural operations; accessory agricultural structures; see allowed uses table.
Key standards: Minimum parcel size varies by ag zone; typical setbacks: Front 20 ft, Interior side 15 ft, Street side 20 ft, Rear 25 ft.
Design review: Agricultural “P” uses with construction may require Zoning Clearance or Site Plan and Design Review; new non-ag buildings or large site work can trigger review under § 18.122.020.

A-1-40 (General Agricultural, 40-acre min.)

Purpose/uses: As above, emphasizing larger lots.
Key standards: 40 acres minimum; same baseline setbacks as A‑1.
Design review: Same triggers as A‑1.

A-2 (Exclusive Agricultural)

Purpose/uses: Intensive agriculture; agricultural support. Noted separately for minimum parcel size.
Key standards: 160 acres minimum; same baseline setbacks.
Design review: Same triggers as A‑1; proximity to sensitive habitat or waterways may invoke sensitive-site review.

R-R (Rural Residential)

Purpose/uses: Large-lot residential.
Key standards (selected): Interior parcel minimums; front setbacks typically 30–50 ft depending on utilities; height 30–35 ft. See Table 2‑4.
Design review: New single-family homes are generally exempt unless on a sensitive site; additions visible from right‑of‑way may trigger review if “significant.”

R-1 and R-1-5000 (Single-Family Residential)

Purpose/uses: Urban single-family neighborhoods; R‑1‑5000 allows smaller lots.
Key standards (selected): Front 15–20 ft, Interior side 5 ft, Rear 15 ft, Height 30 ft.
Design review: New SFDs not on sensitive sites are generally exempt; multi‑lot subdivisions and street‑visible façade changes can require review via Table 6‑3.

R-2 (Two-Family Residential)

Purpose/uses: Duplexes/townhouses; moderate density.
Key standards: Front 20 ft, Interior side 5/12 ft (see table note), Rear 15 ft, Height 45 ft.
Design review: New duplexes and multi-unit projects trigger design review; objective standards apply if pursuing the streamlined path.

R-3 (Medium-Density Multi-Family)

Purpose/uses: Multi-family up to typical 15 du/ac; often near services/major streets.
Key standards: See Table 2‑4; Height up to 60 ft; setbacks per table; pedestrian connectivity emphasized.
Design review: Required for new multi-family; objective standards in streamlined cases.

R-4 (High-Density Multi-Family)

Purpose/uses: Higher density multi-family (up to typical 33 du/ac).
Key standards: Height up to 60 ft; other standards per Table 2‑4; pedestrian orientation.
Design review: Required for new multi-family; objective standards in streamlined pathway.

M-H (Single-Family Mobile Home Residential)

Purpose/uses: Mobile/manufactured home areas in Urban Communities.
Key standards: See Table 2‑4 (e.g., Front 10 ft, Height 15 ft).
Design review: Exterior changes visible from the street may trigger review; sensitive sites may elevate to review.

C-P, C-1, C-2, C-3, H-I-C, MU (Commercial/Mixed-Use)

Purpose/uses: From professional office (C‑P) and neighborhood commercial (C‑1) to general (C‑2) and heavy commercial (C‑3), highway‑oriented (H‑I‑C), and MU mixed-use.
Key standards (selected): Commercial height commonly 35–75 ft depending on zone; setbacks often minimal (e.g., interior sides at 0 ft in many cases). See Table 2‑6.
Design review: New nonresidential buildings and “significant” exterior changes require review; by-right commercial projects that involve construction may still need Site Plan and Design Review.

B-P, M-1, M-2 (Industrial)

Purpose/uses: B‑P business park (low-impact, campus-like), M‑1 light manufacturing, M‑2 general manufacturing.
Key standards: Typical industrial setbacks Front 15 ft, Sides 0–10 ft, Rear 0 ft; minimum parcel sizes 8,000–10,000 sq ft. See Table 2‑8.
Design review: New structures and visible exterior modifications commonly require review; “by‑right” industrial uses with construction can trigger Site Plan and Design Review per § 18.16.020(C).

SPZ — Special Planning Zones (e.g., Castle Commerce Center and Airport SPZ)

Purpose: Protect unique land uses/resources with customized regulations; may function as overlays with zone‑specific development standards and design guidelines.
Castle SPZ goals include cohesive development within the reuse plan, airport‑oriented operations, and quality development standards/design guidelines.
Design review: Verify SPZ‑specific procedures and guidelines; County may apply additional standards and processes within the SPZ.

Checklist

Confirm your parcel is in unincorporated Merced County and identify applicable base zone and any SPZ/overlays on the Zoning Map.
Screen for triggers: unit count, nonresidential work, visibility from ROW, grading, relocation, County projects, “significant” factors, and “sensitive site” attributes.
Confirm if any exemption applies (e.g., sub‑500 sq ft invisible addition, like-for-like exterior work not visible from ROW).
Prepare a complete application package per Chapter 18.112; include materials to support required findings and standards of review (site plan, elevations, materials/colors, landscape plan, lighting/signage concepts, circulation, grading).
Cross-check objective standards in your zone (setbacks, height, coverage) and any applicable objective housing standards if using the streamlined path.
Coordinate with related chapters for parking, landscaping, and signage integration.
Plan for noticing/appeals timelines; public hearing is only required if referred/elevated or requested.
Track time limits: approvals typically expire if not exercised in 12 months; seek extensions early.

Risks & Ambiguities

Issue	Why it matters	What to verify
“Significant” project threshold	Director’s call determines if review is required	Provide context visuals; ask the Director early; note appeal path to Commission.
“Sensitive site” designation	Elevates otherwise exempt work into design review	Check proximity to mapped habitat/waterways/slopes and cultural resources; confirm with staff.
Visibility from ROW	Triggers vs. exemptions often hinge on visibility	Field photos, street views, and photo‑sims to establish visibility.
Concurrent permits	Higher Review Authority may decide design review	If coupled with CUP/PD, design review goes with that decision-maker.
Objective vs. discretionary standards	Streamlined housing path uses objective criteria	Confirm eligibility under Gov. Code 65913.4 and § 18.122.100 before design.
Timing/expiration	Approvals lapse if not exercised	Note 12‑month commencement and extension procedures.

Plain-English Summary

In unincorporated Merced County, design review checks whether a new building or visible exterior change fits local standards and its surroundings. Multi-unit housing and most new nonresidential buildings go through it; minor hidden changes may be exempt. The Director usually decides, using clear design criteria and zone standards, and you can appeal if needed.

Source References

Merced County Zoning Code, Title 18 — Site Plan and Design Review: § 18.122.010–.100 (purpose, applicability, sensitive sites, exemptions, review authority, standards, findings, conditions, issuance/expiration, modifications, streamlined objective housing standards).
Administration and Processing: § 18.110–18.114; § 18.130; § 18.140–18.146 (review authorities, application processing, appeals, notices, permit time limits).
Zones and Development Standards (selected):
- Agricultural: § 18.10.020; Table 2‑2.
- Residential: § 18.12.020(D); § 18.12.030–.040; Table 2‑4.
- Commercial: § 18.14.020; Table 2‑6.
- Industrial: § 18.16.020–.030; Table 2‑8.
- Special Planning Zones (SPZ): § 18.18.010–.020.
Cross-referenced chapters used in design review: Ch. 18.34 (Fences), 18.36 (Landscaping), 18.38 (Off‑Street Parking), 18.44 (Sign Regulations).

Sources

Retrieved passages

Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (Article 7) High relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (chapter and) High relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code High relevance
Merced County Zoning Code (§ 18.110.010.) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code Medium relevance
Merced County Zoning Code (Title 17) Medium relevance
Merced County Zoning Code (Title 17) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (§ 2) High relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (section shall) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (Article 2) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (§ 2) Medium relevance
Merced County Zoning Code (Article 6) Medium relevance

Cited sections

Official Merced County code library

Frequently asked questions

Do I need design review for a single-family home in unincorporated Merced County?

Usually no—single-family homes are exempt unless the site is “sensitive” (e.g., steep slopes >10%, near lakes/streams, mapped habitat, or cultural/historic resources). The Director can require review on sensitive sites, and that call is appealable.

What counts as a “significant” project that triggers design review?

The Director looks at visibility from the street, height/mass/site disturbance, surrounding context, and potential adverse impacts. This determination can be appealed to the Commission.

Are there design-review exemptions for minor exterior work?

Yes. Examples include additions under 500 sq ft not visible from a public right‑of‑way, exterior changes not visible from the public right‑of‑way, maintenance resurfacing/restriping of parking (if minimum parking remains), like‑for‑like doors/windows/roofing, certain accessibility improvements, and similar minor work.

Who decides my design review—staff or the Planning Commission?

Most items are decided by the Director; the Commission hears appeals and elevated cases. If your project is bundled with another permit (e.g., Conditional Use Permit), the higher Review Authority will decide both.

How long is a design-review approval good for?

Approvals typically expire if not “exercised” (construction commenced) within 12 months of approval. You can request extensions—generally up to three additional 12‑month periods—if you apply before expiration and findings remain valid.

Do multi-family projects have objective design standards?

Yes. If eligible for the State’s streamlined ministerial approval (Gov. Code 65913.4), Merced County applies objective design standards, with detailed criteria for R‑2 and expectations for R‑3/R‑4 projects (façade articulation, materials, entries, connectivity, screening).

Will parking, landscaping, and signage be reviewed as part of design review?

Yes. The standards in Chapters 18.38 (Off‑Street Parking), 18.36 (Landscaping), and 18.44 (Signs) are applied during design review to ensure integrated site design.

What if my project is near a historic resource or in a special planning zone?

Proximity to cultural/historic resources can make your site “sensitive,” potentially requiring design review. Special Planning Zones, such as the Castle Commerce Center and Airport SPZ, have added regulations/guidelines. Verify parcel‑specific SPZ details with the County.

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