Local zoning · San Mateo County

San Mateo County — Design Review

Q: What minimum plans and materials are required for a Design Review application?

At minimum: a location map; site plan (min 1" = 20' ); building elevations (min 1/4" = 1' ); landscape plans; a written explanation demonstrating conformance to applicable design standards; and any additional materials required for special areas (FAR for RH, floor area for S-70/S-90/S-100, grading quantities). § 8.256.060 .

Q: How long does a design approval last?

Design approvals expire five (5) years from the date of approval if all other required permits are not obtained and construction begun; extensions of one year at a time may be granted for good cause by the Design Review Administrator. § 8.256.130–120 .

Q: Do coastal or RM-CZ parcels have extra design-review steps?

Yes — developments in the RM-CZ must obtain a Development Review Permit that consolidates zoning, subdivision and environmental reviews and applies additional environmental and site-design criteria (view protection, habitat avoidance, minimized grading). § 8.294.010–050 .

Q: Can minor changes to an approved design be made without a new review?

The Design Review Administrator may approve minor amendments in writing without public notice or hearing (examples: interior changes, minor window/door relocations, minor roof pitch adjustments), but more substantial modifications require a new application. § 8.256.120 .

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

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Last reviewed: July 3, 2026

Overview

Design review in unincorporated San Mateo County is a county-level, site-and-appearance review applied where the zoning map is combined with the DR (Design Review) overlay and in several community-specific chapters (e.g., North Fair Oaks, Midcoast, Emerald Lake Hills). The rules set who reviews a proposal (Design Review Committee vs. Design Review Administrator), what materials are required, what standards apply (community-specific and general design criteria), and the procedural controls such as exemptions, amendments and expiration. See the County Zoning rules for how design standards interact with development standards, parking, overlay districts, and landscaping and screening in unincorporated areas. The code that governs design review is found in Title 8 (Zoning & Development Code), primarily Chapter 8.256 and related community chapters. § 8.256.030 and § 8.256.060 explain applicability and application requirements.

How this page is organized

District-by-district summaries (actual San Mateo County district names / zones where design review rules appear)
A decision-relevant standards table you can scan quickly
Practical applicant checklist, risks and ambiguities, plain-English summary
Source references (ordinance § citations with County file references)

District-by-district design review breakdown

Notes on terminology: the County code combines the DR overlay with base zoning in various places; design review rules also appear as community-specific site development or development review chapters. Where the Code names a community or zone explicitly, that precise name is used below and grounded to its § citation.

Design Review District (DR overlay)

Purpose: To require design approval for exterior construction, grading that requires a permit, or tree cutting in areas combined with the DR overlay; to improve local building and site design where zoning controls alone are insufficient. § 8.256.030; intent and scope also in § 8.256.010-020.
Typical permitted uses: Uses are controlled by the underlying zoning district; design review does not change permitted uses, it reviews appearance and site design. Not a substitute for a use permit where one is required (design review recommendations may be forwarded to the decision-maker on the use permit). § 8.256.070(B).
Key dimensional / procedural standards:
- Design review applies to "any district which is combined with the DR District" for new exterior construction and certain grading/tree permits (exemptions possible). § 8.256.030–040.
- Pre-design conference required before submitting application. § 8.256.050.
- Application content: location map, site plan, elevations, landscape plan, written conformance statement, and special/FAR or grading info where applicable. § 8.256.060.
Where it applies: Wherever the County zoning map shows a DR overlay combined with a base zone; check parcel zoning to confirm. Verify on a parcel basis with County maps. Verify with the jurisdiction.

Emerald Lake Hills & Oak Knoll Manor (areas zoned RH/DR only)

Purpose: Apply hillside residential design standards to protect hillsides and neighborhood character. § 8.256.150 (Site/Architectural standards for Emerald Lake Hills & Oak Knoll Manor).
Typical permitted uses: Those allowed in the underlying Residential Hillside (RH) district; design review focuses on new dwellings, additions, grading and tree protection. § 8.256.150 (references RH/DR).
Key dimensional / design standards:
- Emphasize siting to minimize tree removal and grading; maintain natural topography, privacy and sunlight for neighbors. § 8.256.150(A, C).
- Architectural compatibility with predominant local styles (bungalow, craftsman, ranch) and control of bulk on hillsides. § 8.256.150(B–D).
- Additional site-specific items (FAR and grading quantities) required in the design-review application in these areas. § 8.256.060(F–H).
Where it applies: Parcels in Emerald Lake Hills and Oak Knoll Manor that are zoned RH/DR. Verify parcel zoning.

Palomar Park and Devonshire

Purpose: Community-specific design standards (small-lot residential neighborhoods) to protect scale and neighborhood character. § 8.256.070(A) and § 8.256.150 provisions applicable.
Typical permitted uses: Underlying residential uses; design review applies to new exterior construction and certain grading/tree work. § 8.256.030.
Key dimensional standards: The Code references S-70, S-90, S-100 spacing/floor area limits specifically for these areas and requires applicants to supply building floor area per those zones as part of the package. § 8.256.060(G).
Where it applies: Parcels identified as Palomar Park or Devonshire on the County map; confirm with parcel records.

Midcoast (residential design review)

Purpose: Midcoast community design review for single- and multiple-family residential construction; the Design Review Committee reviews residential proposals in Midcoast. § 8.256.070(A)(4).
Typical permitted uses: Residential development consistent with underlying residential zoning. § 8.256.070.
Key points: Midcoast residential projects follow the Design Review procedures in Chapter 8.256; coastal zone considerations may also apply (verify coastal provisions). § 8.256.070 and related coastal chapters.

North Fair Oaks — CMU and NFO zones (CMU-1, CMU-2, CMU-3, NMU-ECR, M-1/NFO, M-1/Edison/NFO)

Purpose: The North Fair Oaks Site Development Permit / design review process provides a unified staff-level design and zoning review and site development permit regime (intent to apply ministerial standards for many projects). § 8.308.020–030.
Typical permitted uses: Uses allowed under the specific North Fair Oaks zoning districts (commercial mixed-use, neighborhood mixed-use, limited industrial) — design review is the process for shaping appearance and site improvements for projects that do not require a use permit. § 8.308.030.
Key dimensional / procedural standards:
- For projects not requiring a use permit, staff-level Site Development Plan (SDP) review applies; applicants must provide the full SDP information (including items in § 8.256.060 plus transportation, landscaping, signage, stormwater, and environmental comparisons). § 8.308.040.
- Where a use permit is required, the use-permit decision-maker handles the project but applies design review recommendations. § 8.308.030.
Where it applies: Within the geographic North Fair Oaks planning area where the NFO zones are mapped. Verify parcel location.

Resource Management — Coastal Zone (RM-CZ)

Purpose: Require submission of all developments in the RM-CZ to a Development Review Permit that consolidates necessary criteria (zoning, subdivision and environmental review) into one procedure. § 8.294.010–020.
Typical permitted uses: Depends on underlying RM-CZ allowances; the code requires any "development" as defined in § 8.138.040 to obtain a Development Review Permit. § 8.294.020.
Key standards: General review criteria (environmental quality, site design, minimize grading, protect views and habitat) are spelled out in § 8.294.030–050 and are additional to Chapter 8.296 Development Review Permit procedures.
Where it applies: Areas designated RM-CZ on the County zoning map (Coastal Zone parcels). Verify coastal mapping and possible Coastal Commission certifications.

Development Design Criteria (County-wide / special resource areas)

Purpose: County-wide design criteria and special-area supplements — environmental design, site/building design criteria, utilities and cultural resource protections. § 8.318.100–110.
Typical effect: These criteria supply objective/general standards that Design Review Administrators, Committee and decision-makers apply when reviewing projects. § 8.318.110 lists the general design criteria (minimize grading, fit topography, small screened parking areas, utility screening, avoidance of habitat impacts).

Quick-reference table — decision-relevant design review standards

Rule / Topic	Key point a reviewer will check	Code reference
Who reviews where	Design Review Committee reviews projects in Emerald Lake Hills, Oak Knoll Manor (RH/DR), Palomar Park, Devonshire, and residential Midcoast; Design Review Administrator reviews elsewhere in DR District. § 8.256.070(A–B).	§ 8.256.070
Applicability of DR overlay	Applies in any district combined with DR for new exterior construction, grading/tree cutting that requires permits; exemptions by DRA possible. § 8.256.030–040.	§ 8.256.030–040
Application materials	Site plan (1"=20'), elevations (1/4"=1'), landscape plan, written conformance statement, FAR/building floor area when applicable, grading quantities. § 8.256.060.	§ 8.256.060
Expiration of design approval	Approvals expire five (5) years if other permits not obtained and construction begun; one-year extensions possible. § 8.256.130.	§ 8.256.130
Hillside design controls	Emerald Lake Hills / Oak Knoll Manor: minimize tree removal, minimize grading, step buildings with slope, avoid blank walls/garage dominance. § 8.256.150(A–F).	§ 8.256.150
North Fair Oaks process	Staff-level ministerial review for many CMU/NMU projects without a use permit; SDP must include items from § 8.256.060 plus transportation, stormwater, signage, etc. § 8.308.030–040.	§ 8.308.030–040

Checklist — what an applicant must provide (minimum)

Complete the required pre-design conference with the Design Review Administrator. § 8.256.050.
Submit a Design Review application form and fees (as set by Board resolution). § 8.256.060(J).
Provide a location map, scaled site plan (min 1" = 20'), existing/proposed contours, lot coverage, setbacks, and grading info where applicable. § 8.256.060(A–B).
Provide building elevations (min 1/4" = 1') showing materials, colors, heights, roof equipment, fences and other exterior fixtures. § 8.256.060(C).
Submit a landscape plan that meets Director's minimum standards and tree protection/replacement information when required. § 8.256.060(D) and § 8.256.140–150.
Written explanation of how the design conforms to applicable design review standards/guidelines (community-specific statements required). § 8.256.060(E).
For North Fair Oaks projects: include SDP items such as street tree and bicycle parking plans, traffic/transit analysis, environmental comparisons and C.3 stormwater measures. § 8.308.040.
Verify any additional special-area criteria (RM-CZ, scenic corridor, primary resource areas) and include required analyses. § 8.294.030–050, § 8.314.120–130.

Risks & Ambiguities

Issue	Why it matters	What to verify
DRA exemption discretion	The Design Review Administrator may exempt minor works; that discretion is subjective and can affect whether a full design review is required. § 8.256.040.	Confirm with the DRA in a pre-design conference and get written exemption documentation if granted.
Which body reviews my project	Some communities (Emerald Lake Hills, Palomar Park, Devonshire, Midcoast) are explicitly assigned to the Design Review Committee; elsewhere the DRA reviews. Misidentifying the reviewer causes delays. § 8.256.070.	Verify your parcel is within the named community or DR overlay; ask staff for the assigned reviewer.
Interaction with other entitlements	When a project requires a use permit, variance or subdivision, design review becomes a recommendation rather than independent final action — this changes appeal and hearing procedures. § 8.256.070(B).	Confirm whether your project requires other permits and whether design review will be consolidated with those hearings.
Hillside grading and tree protection details	Emerald Lake Hills / Oak Knoll Manor have explicit tree-protection and grading data requirements that must be shown in the application; omissions commonly trigger resubmittals. § 8.256.150; § 8.256.060(H).	Verify exactly which grading/tree reports are required, and whether an arborist or landscape architect certification is needed.
Coastal / RM-CZ overlay requirements	Projects in the RM-CZ or Coastal Zone may require consolidated Development Review Permits and additional environmental or coastal findings. § 8.294.020–030.	Confirm coastal applicability and additional submittal items early.

Plain-English Summary

If your property lies in an unincorporated area mapped with the DR overlay or within one of the named communities (Emerald Lake Hills, Oak Knoll Manor, Palomar Park, Devonshire, Midcoast, North Fair Oaks, RM-CZ), you must complete a pre-design meeting and submit a package of drawings and a written explanation that shows how your project meets the County’s design standards; the project will be reviewed by either the County’s Design Review Administrator or the Design Review Committee depending on location and project type. The precise materials, timeframes, whether appeals are available, and whether additional permits (use permit, coastal review) are needed are all spelled out in the County Code; verify your parcel and the assigned reviewer with County staff. § 8.256.050–070, § 8.256.060.

Source References

San Mateo County Ordinance Code, Title 8 – Zoning & Development Code, Chapter 8.256 (Design Review) — applicability, exemptions, pre-design conference, application requirements, action on application, committee/administrator roles, amendment, expiration. § 8.256.030–140.
§ 8.256.060 — Application requirements (site plan, elevations, landscaping, written explanation, FAR/floor area and grading where applicable).
§ 8.256.070 — Who takes action (Design Review Committee for specific communities; Administrator elsewhere), and recommendation process when combined with other permits.
§ 8.256.150 — Standards for Emerald Lake Hills, Oak Knoll Manor and Devonshire (site planning, architecture, facades, tree protection).
Chapter 8.308 — North Fair Oaks Site Development Permit and ministerial design/zoning review (CMU/NMU/NFO zones). § 8.308.020–040.
Chapter 8.294 — RM-CZ Development Review criteria and requirement for a Development Review Permit. § 8.294.010–050.
Chapter 8.318 — County Development Design Criteria (general design criteria). § 8.318.100–110.
Daylight-plane and façade articulation rules referenced for residential development standards: § 8.208.100.

If you need the specific parcel mapping or to confirm whether a parcel is in the DR overlay or a named community (Emerald Lake Hills, Palomar Park, Devonshire, Midcoast, North Fair Oaks, RM-CZ), verify with the County planning staff and parcel zoning map. Not found in retrieved materials: a single consolidated County "design review" webpage URL—use County Planning staff for parcel-specific confirmation.

Sources

Retrieved passages

San Mateo County Zoning Code (Section 6565.6.7) High relevance
San Mateo County Zoning Code (Chapter 8.300) High relevance
San Mateo County Zoning Code (Chapter 20A.2) High relevance
San Mateo County Zoning Code (Section 8.138.040) High relevance
San Mateo County Zoning Code (Section 6565.2.1.B) High relevance
San Mateo County Zoning Code (§ 6300.9.11.60) High relevance
San Mateo County Zoning Code (Title 8) High relevance
San Mateo County Zoning Code (Title 8) High relevance

Cited sections

Official San Mateo County code library

Frequently asked questions

Do I need design review in unincorporated San Mateo County?

If your parcel is in a zoning district combined with the DR overlay or in a named community covered by the County’s design regulations (e.g., Emerald Lake Hills, Oak Knoll Manor, Palomar Park, Devonshire, Midcoast, North Fair Oaks), then yes — most new exterior construction, grading requiring permits, or tree cutting that requires a permit is subject to design review unless exempted by the Design Review Administrator. § 8.256.030–040.

Who reviews design review applications in San Mateo County?

Projects in specified communities (Emerald Lake Hills, Oak Knoll Manor (RH/DR), Palomar Park, Devonshire, and residential Midcoast) are reviewed by the Design Review Committee; in all other DR areas review is by the Design Review Administrator. Recommendations from either body are forwarded when other permits (use permits, variances) are needed. § 8.256.020–070.

What minimum plans and materials are required for a Design Review application?

At minimum: a location map; site plan (min 1" = 20'); building elevations (min 1/4" = 1'); landscape plans; a written explanation demonstrating conformance to applicable design standards; and any additional materials required for special areas (FAR for RH, floor area for S-70/S-90/S-100, grading quantities). § 8.256.060.

What happens if my project also needs a use permit or variance?

When another discretionary permit (use permit, variance, subdivision) is required, the Design Review Committee or Administrator acts in a recommending role and the decision-maker on the other permit considers the design recommendation; the decision-maker may refer revisions back for additional design review. § 8.256.070(B–C).

How long does a design approval last?

Design approvals expire five (5) years from the date of approval if all other required permits are not obtained and construction begun; extensions of one year at a time may be granted for good cause by the Design Review Administrator. § 8.256.130–120.

What special rules apply in North Fair Oaks?

North Fair Oaks uses a Site Development Permit/Design and Zoning review process where many projects that do not require a use permit are reviewed ministerially by staff using objective SDP standards; the SDP must include items listed in § 8.256.060 plus transportation, stormwater, signage and environmental comparison materials. § 8.308.020–040.

Are there standard design themes or materials the County prefers?

Yes — the County’s community-specific standards (for example, Emerald Lake Hills guidance) ask that new buildings be compatible with predominant local architectural styles and use durable, authentic materials; generic County development criteria encourage materials/colors that blend with surroundings and minimize visual impacts. See § 8.256.150 and § 8.318.110.

Do coastal or RM-CZ parcels have extra design-review steps?

Yes — developments in the RM-CZ must obtain a Development Review Permit that consolidates zoning, subdivision and environmental reviews and applies additional environmental and site-design criteria (view protection, habitat avoidance, minimized grading). § 8.294.010–050.

Can minor changes to an approved design be made without a new review?

The Design Review Administrator may approve minor amendments in writing without public notice or hearing (examples: interior changes, minor window/door relocations, minor roof pitch adjustments), but more substantial modifications require a new application. § 8.256.120.

Where do parking and stormwater fit into design review?

The design-review application and community SDP rules require parking and stormwater to be addressed; North Fair Oaks SDPs specifically require bicycle parking and C.3 stormwater treatment measures, and general County design criteria call for small, screened parking areas and on-site stormwater management. See § 8.256.060, § 8.308.040, and § 8.318.110. ---

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