Local zoning · San Francisco County

San Francisco County — Overlay Districts

Q: What is an overlay district in San Francisco County and how does it change zoning?

An overlay district in San Francisco County is usually a Special Use District or a Height and Bulk District that sits on top of the base zoning and modifies uses, numeric standards, or approval procedures for mapped areas. The overlay’s controlling SUD text and any incorporated Design for Development/DSG govern where they conflict with base rules (see § 249.52 , § 249.7 ) .

Q: What can I build on a lot inside the Treasure Island / Yerba Buena Island SUD?

Permitted uses include residential (dwelling units, live/work, certain supportive and senior housing) plus mixed‑use, retail, and institutional categories as shown in the SUD’s Figure 3 use table; some uses are Island Conditional (IC) while others are permitted (P). Height and bulk are controlled by HT‑14 and the project’s Design for Development, and some areas are in the Tidelands Trust Overlay Zone with special jurisdictional rules (§ 249.52) .

Q: What are the Treasure Island height and separation rules I must watch for?

The SUD relies on sectional HT maps (HT‑14) and implements Flex Height Zones (up to 450 ft in some areas) plus tower‑separation corridors and minimum clearances (e.g., 115 ft circular offsets and 500 ft corridors in identified blocks) — all defined in the SUD and its Design for Development (§ 249.52(e)(6)) .

Q: Do overlays change parking requirements in the County?

Yes — many SUDs explicitly modify parking rules (examples: some HOPE SF SUDs report no minimum off‑street parking for certain non‑residential uses or caps on total parking). Always verify the overlay text for parking changes and consult the County Parking rules referenced in the SUD (see § 249.76(e)(5) and § 249.75) .

Q: Do I need a special approval process or is the Planning Director authorized to act?

Overlay texts specify the review path. Some overlays delegate authority to the Planning Director for certain decisions or to other bodies (e.g., TIDA for tidelands), while others reserve decisions to the Planning Commission or require Conditional Use / Planned Unit Development approvals; check the SUD’s procedural divisions (e.g., § 249.52 and § 249.26) for who acts on applications (§ 249.52(e)(3)–(4)) .

Q: How do I tell if my parcel is within an overlay map (SU / ZN / HT)?

Overlay applicability is map‑based. The SUD text references sectional maps (SU maps, ZN maps, HT maps) by name (for example, SU14, ZN14, HT14). To confirm parcel coverage, request the applicable Sectional Map from the Planning Department and compare your assessor parcel to the SUD maps (§ 249.52(e)(1)–(4)) .

Q: Will an overlay stop me from using state‑required ADU rights?

The retrieved SUD texts did not include overlay‑specific ADU provisions in the materials reviewed (Not found in retrieved materials). ADU entitlements are governed by state ADU law plus any local implementing rules — verify with the jurisdiction and the overlay text whether the SUD imposes any additional constraints (Verify with the jurisdiction).

Q: What is a Major Modification in an overlay like the San Francisco Gateway SUD?

A Major Modification is commonly defined as a deviation of 15% or more from any numeric or dimensional standard in the SUD/DSG; Minor Modifications are less than 15% . This classification affects process, findings, and public notice (§ 249.7(c)) .

Q: Do overlays change sign rules?

Yes — some SUDs either adopt base Article 6 sign rules or establish special sign districts (e.g., Stonestown Special Sign District under § 608.10 ) that modify allowable signage and standards (§ 249.9; § 608.10) .

Q: If my proposed project is inconsistent with an SUD, can I apply for exceptions?

Certain SUDs provide explicit paths for Conditional Use authorization, Planned Unit Development modifications, or Director/Commission exceptions (for example, § 249.26(c) and the SUD text that allows conditional exceptions). Where a SUD grants exceptions, the SUD text controls the scope and findings required (§ 249.26(c)) .

Overlay Districts under the San Francisco County local zoning and planning code, with the controlling citations.

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Last reviewed: July 3, 2026

Overview

Overlay districts in the San Francisco County Planning/ Zoning ordinance are implemented as Special Use Districts, Height and Bulk Districts, and unique overlays (for example, the Tidelands Trust Overlay Zone) that modify or supersede underlying zoning controls for targeted areas and projects. These overlays apply to development in the county’s unincorporated areas and must be interpreted together with the underlying zoning map, any Design for Development or Design Standards and Guidelines adopted for the overlay, and the Planning Code provisions that the overlay explicitly preserves or supersedes. See the County’s base Zoning rules and the adopted Development Standards for interactions between overlays and base rules.

Note: the materials retrieved are the City & County Planning Code provisions creating the Special Use and Height/Bulk districts; treat every overlay below as a site- or project-specific regulatory layer that overrides or refines the underlying district where it so states (verify with the jurisdiction for parcel-specific application) (§ 249.52, § 249.75) .

How San Francisco’s overlays are structured (short primer)

Many overlays are labeled Special Use Districts (SUDs) (e.g., Treasure Island/Yerba Buena Island SUD, Sunnydale HOPE SF SUD) and include embedded rules, a Design for Development or DSG, and figures/maps that set permitted uses, height, bulk, and special procedural rules (§ 249.52, § 249.75, § 249.7) .
Some overlays are implemented as Height and Bulk Districts that sit on top of use districts (example: Treasure Island/Yerba Buena Island Height & Bulk District, HP Height and Bulk, 48/78‑X) and reference sectional Height & Bulk maps (HT maps) for numeric limits (§ 263.26, § 263.35) .
Overlays frequently incorporate a separate adopted guidance document (Design for Development or Design Standards & Guidelines) that controls dimensional measurement rules and details; where the SUD and the Design for Development conflict, the SUD controls (§ 249.52, § 249.7) .
Overlays may create special administration (e.g., TIDA for Treasure Island tidelands, Planning Director delegations) and unique approval routes; check the overlay language for which agency has jurisdiction (§ 249.52(b), § 249.52(e)(4)) .

When you see an overlay, also check these topic areas (first natural mentions linked): Development Standards, Zoning, Parking, and Design Review.

Overlay district — district-by-district breakdown

Treasure Island / Yerba Buena Island Special Use District (TI / YBI)

Purpose: Implement the Treasure Island/Yerba Buena Island redevelopment program and related Development Agreement; regulate uses, heights, and unique waterfront/tidelands jurisdictional issues (§ 249.52(a)–(e)) .
Where it applies: the islands identified on Sectional Map SU14 / Zoning Map ZN14; portions are also shown as the Tidelands Trust Overlay Zone on project figures (§ 249.52(a)–(c)) .
Typical permitted uses: residential (dwelling units, live/work, senior/assisted living, supportive housing) and a broad set of mixed‑use, retail, institutional uses organized in the overlay’s Figure 3 use table; some uses are principal (P) and others Island Conditional (IC) (§ 249.52(e)(2); Figure 3) .
Key dimensional / development controls:
- Height and bulk are controlled by Sectional Map HT‑14 and the project “Design for Development” (height measurement and bulk rules may differ from Article 2.5 and Article 1.2) (§ 249.52(e)(4)(A)–(C); § 263.26) .
- Portions of the islands are subject to the Tidelands Trust Overlay Zone, and TIDA has exclusive horizontal-development jurisdiction in those areas; Planning Commission or Planning Director retains review for vertical development outside tidelands or by specific agreement (§ 249.52(b)–(d)) .
- Overlay prescribes specific building separation/tower separation and “Flex Height Zone” rules (e.g., Flex Height maximums up to 450 ft on Treasure Island; corridor and 115‑ft / 500‑ft separation rules) — see the overlay tower separation rules (§ 249.52(e)(6)(A)–(C)) .
Practical note: the SUD incorporates a Design for Development that may set different setback, open‑space (e.g., 80 sf per unit), and measurement rules; the SUD controls where there is any conflict (§ 249.52(e)(4)(D) and related) .

Treasure Island — Tidelands Trust Overlay Zone

Purpose / jurisdiction: designates the tidelands areas subject to State trust and TIDA authority; TIDA has exclusive jurisdiction over certain horizontal development and some approvals; Planning Commission retains review in other circumstances (§ 249.52(b)–(d)) .
Practical consequence: applications in the Tidelands Trust Overlay Zone may require TIDA review/approvals in addition to Planning Department actions; check overlay figures and the Design for Development for the exact line of authority (§ 249.52(b)–(d)) .

Sunnydale HOPE SF Special Use District

Purpose: Implement the Sunnydale HOPE SF redevelopment, replace public housing with mixed‑use/mixed‑income development (§ 249.75(a)) .
Where it applies: boundaries shown on Sectional Map SU‑11 (§ 249.75(a)) .
Uses: adds NC‑2 neighborhood commercial uses to an underlying RM‑1 (with exclusions — Liquor Stores and Medical Cannabis Dispensaries are not permitted) and requires “active uses” along specified ground‑floor frontages (§ 249.75(d)(2)(A)–(B)) .
Dimensional standards and controls:
- Height per Sectional Map HT‑11; building bulk and setbacks are governed by the adopted Design Standards and Guidelines rather than some base Planning Code articles (§ 249.75(d)(4)(A)–(C)) .
- Usable open space: 80 sq ft per unit (Design Standards specify methods) (§ 249.75(d)(4)(D)) .
- No minimum off‑street parking requirement for uses in the SUD in some implementations (see Potrero HOPE SF and other HOPE SF SUD language for variations) (§ 249.76(e)(5)) .

Potrero HOPE SF Special Use District

Purpose: implement Potrero HOPE SF redevelopment, replace public housing with mixed‑use, mixed‑income development (§ 249.76(a)) .
Controls: uses, heights, bulk, and site controls are set by the SUD and the Potrero Design Standards & Guidelines; often no minimum off‑street parking and special car‑share requirements apply (see § 249.76(e)(5)) .

Hunters Point Shipyard Phase 2 Special Use District and HP Height & Bulk

Purpose: enable Candlestick Point–Hunters Point Shipyard Phase 2 redevelopment and implement the Hunters Point Shipyard Redevelopment Plan and Design for Development (§ 249.51(c)) .
Controls: this SUD and its Redevelopment Plan supersede standard Planning Code provisions in favor of the project documents; height/bulk are governed by the Hunters Point documents (see § 263.25 and § 249.51) .

San Francisco Gateway Special Use District

Purpose: accommodate large‑scale PDR (Production, Distribution, Repair) use with tailored controls; includes a DSG (Design Standards & Guidelines) and Major/Minor modification rules (§ 249.7) .
Controls: SUD defines “Major Modification” (> 15% deviation) and “Minor Modification” (< 15%) thresholds for changes to numeric standards in the DSG (§ 249.7(c)) .

Stonestown Mixed‑Use Special Use District and Stonestown Special Sign District

Purpose: implement a form‑based approach for the Schlage Lock / Visitacion Valley site and provide specific sign regulations via a special sign district (§ 249.9; § 608.10) .
Controls: SUD incorporates a Design for Development and may create zones (Zone 1, Zone 2) with tailored bulk and use rules; also prescribes special sign controls via § 608.10 (Stonestown Special Sign District) .

Balboa Reservoir Special Use District and 48/78‑X Height & Bulk Districts

Purpose: site‑specific height/bulk and block‑level controls for Balboa Reservoir development; blocks have individually prescribed heights (see Figure 249.90‑2) (§ 263.35) .

2245 Post Street Special Use District and Central Neighborhoods Large Residence SUD

2245 Post St SUD (§ 249.26) enables institutional uses with FAR limits and bulk exceptions; Central Neighborhoods Large Residence SUD (§ 249.92) implements additional review controls for large‑residence projects and applies to mapped neighborhoods (§ 249.26; § 249.92) .

Quick decision table — most decision‑relevant items

Overlay District (bold)	Most decision‑relevant standards / permitted uses	Code reference
Treasure Island / Yerba Buena Island SUD	Permitted uses: residential (dwelling units, live/work, supportive, senior); Height/Bulk by HT‑14 maps; Tidelands Trust Overlay Zone and TIDA jurisdiction	§ 249.52 ; § 263.26
Sunnydale HOPE SF SUD	Active ground‑floor uses required on specified frontages; 80 sq ft usable open space/unit; height by HT‑11; Liquor & cannabis excluded	§ 249.75; § 145.1
Potrero HOPE SF SUD	Mixed‑use redevelopment rules; no minimum off‑street parking for non‑residential uses; car‑share provisions	§ 249.76(e)(5)
Hunters Point Shipyard Phase 2 SUD	Redevelopment Plan/Design for Development control height & bulk; SUD may supersede base Code	§ 249.51; § 263.25
San Francisco Gateway SUD	Special PDR rules; Major Modification = ≥15% deviation threshold; incorporates DSG	§ 249.7(c)
Stonestown SUD & Special Sign District	Zone 1/Zone 2 distinctions; special sign controls under § 608.10	§ 249.9; § 608.10

Checklist (what an applicant must satisfy for overlays in unincorporated San Francisco County)

Confirm overlay boundary and applicable Sectional Map (SU map, ZN map, HT map) for the parcel and whether the parcel falls in a SUD, Height & Bulk District, or an Overlay Zone (e.g., Tidelands Trust) (§ 249.52; § 263.26) .
Read the overlay's controlling text (SUD §) and any appended/ incorporated Design for Development or Design Standards and Guidelines — the SUD controls where inconsistent (§ 249.52; § 249.7) .
Verify permitted uses in the overlay’s use table (P / IC / blank) and any express prohibitions (e.g., Liquor Store / Medical Cannabis prohibitions in Sunnydale) (§ 249.75(d)(2)) .
Check which agency has jurisdiction (Planning Director, Planning Commission, or other agency such as TIDA) for approvals and interim use authorizations (§ 249.52(b),(e)(4)) .
Confirm height and bulk rules: which HT map applies, and whether the overlay uses alternative height measurement or “Flex Height Zones” (§ 249.52(e)(4)(A); § 263.26) .
Meet overlay-specific design, open‑space, and parking rules (e.g., 80 sq ft/unit open‑space standard, car‑share or parking caps) and confirm whether base Parking rules are superseded (§ 249.75(d)(4)(D); § 249.76(e)(5)) .
If the overlay references a DSG/Design for Development, determine whether your proposal is a Major Modification or Minor Modification and prepare the corresponding justification and public‑notice materials (§ 249.7(c)) .
Check sign rules (some overlays apply special sign districts) and consult the Signage page for interactions (§ 249.9; § 608.10) .
For historic resources within overlays, consult the overlay text and the Historic Preservation standards (if referenced in SUD) — overlay may incorporate separate preservation rules (Not always explicit in SUD text) (§ 249.9) .
If seeking exceptions, check the SUD’s rules on Conditional Use, Planned Unit Development, or Variances and Exceptions and prepare the required findings (§ 249.26(c); § 304) .

Risks & Ambiguities

Issue	Why it matters	What to verify
Tidelands Trust Overlay / TIDA jurisdiction	The overlay assigns some approvals to TIDA rather than Planning; missing this can delay or void needed approvals	Confirm whether parcel sits inside the Tidelands Trust Overlay Zone and whether TIDA or Planning Director controls the specific approval (§ 249.52(b)–(d))
Conflicts between SUD and Design for Development	SUDs frequently incorporate DSGs; some measurement rules (height/bulk/setbacks) are in the DSG, others in SUD text — the SUD controls conflicts	Read both the SUD and the adopted DSG; where inconsistent, the SUD prevails (§ 249.52(e); § 249.7(e))
Parcel-level HT map interpretation	Overlay often references sectional HT maps for numeric limits — map interpretation is parcel‑specific	Verify the parcel’s HT map zone (e.g., HT‑14, HT‑11) with Planning maps and request pre‑application mapping confirmation (§ 249.52(e)(4)(A))
Major vs Minor Modification thresholds	Misclassifying a change can lead to incorrect process and public‑notice requirements	Confirm the overlay’s definition of Major Modification (commonly ≥15%) (§ 249.7(c))
Applicability to “unincorporated” areas	The retrieved materials are City & County Planning Code text for mapped overlays; user‑specific jurisdictional applicability to truly unincorporated county parcels may be unclear	Verify with the Planning Department whether a given overlay map and SUD apply to the subject parcel (Verify with the jurisdiction). Not found in retrieved materials for a general “county-only” overlay application note.
ADUs / state housing overlay interaction	ADU entitlements are governed by state ADU law and local implementation — overlays sometimes modify local standards	Not found in retrieved materials for overlay‑specific ADU guidance; consult local ADU provisions and California ADU law. Verify with the jurisdiction.

Plain‑English summary

Overlay districts in San Francisco County are site‑specific zoning layers (Special Use Districts, Height & Bulk Districts, tidelands overlays) that change which uses, heights, setbacks, parking, and review steps apply to a given property; to proceed you must check the exact overlay map for your parcel, read the overlay’s rule text and any incorporated Design for Development or DSG, and confirm which agency (Planning Director, Planning Commission, or a special authority such as TIDA) has approval jurisdiction (§ 249.52; § 249.75) .

Information Gaps

A consolidated map showing all County unincorporated parcels overlaid by the listed SUDs and Height & Bulk districts: Not found in retrieved materials (verify with Planning maps).
Overlay‑specific ADU rules or how overlays interact with state ADU law: Not found in retrieved materials — consult local ADU provisions and California ADU law.
Parcel‑specific application of HT maps and whether a given lot is inside a Flex Height Zone or Tidelands Trust Overlay Zone: Not confirmed in retrieved materials — Verify with the jurisdiction.

Source References

Planning Code § 249.52 (Treasure Island / Yerba Buena Island Special Use District)
Planning Code § 249.52(b)–(d) (Tidelands Trust Overlay Zone and TIDA jurisdiction)
Planning Code § 263.26 (Treasure Island/YBI Height & Bulk District and related height provisions)
Planning Code § 249.75 (Sunnydale HOPE SF Special Use District — uses, height/map HT‑11, open space)
Planning Code § 249.76 (Potrero HOPE SF Special Use District — parking and programmatic controls)
Planning Code § 249.51 and § 263.25 (Hunters Point Shipyard Phase 2 SUD; related height & bulk exceptions)
Planning Code § 249.7 (San Francisco Gateway SUD — DSG rules; Major/Minor modifications)
Planning Code § 249.9 and § 608.10 (Stonestown Mixed‑Use SUD and Special Sign District)
Planning Code § 263.35 (Balboa Reservoir Special Use District and 48/78‑X Height & Bulk Districts)
Planning Code § 249.26 (2245 Post Street Special Use District)
Planning Code § 249.92 (Central Neighborhoods Large Residence SUD)

Also consult the County pages linked earlier for procedural topics referenced in overlays: Zoning, Development Standards, Parking, Design Review, Signage, Historic Preservation, Variances and Exceptions, and state code reference California Building Standards Code for building code interactions.

Sources

Retrieved passages

San Francisco County Zoning Code (Section 101.1) Medium relevance
San Francisco County Zoning Code Medium relevance
San Francisco County Zoning Code (Section 249.75.) Medium relevance
San Francisco County Zoning Code (Section 249.73.) Medium relevance
San Francisco County Zoning Code (section shall) Medium relevance
San Francisco County Zoning Code (Section Map) Medium relevance
San Francisco County Zoning Code (Section 838) Medium relevance
San Francisco County Zoning Code (Section 249.78) Medium relevance

Cited sections

Official San Francisco County code library

Frequently asked questions

What is an overlay district in San Francisco County and how does it change zoning?

An overlay district in San Francisco County is usually a Special Use District or a Height and Bulk District that sits on top of the base zoning and modifies uses, numeric standards, or approval procedures for mapped areas. The overlay’s controlling SUD text and any incorporated Design for Development/DSG govern where they conflict with base rules (see § 249.52, § 249.7) .

What can I build on a lot inside the Treasure Island / Yerba Buena Island SUD?

Permitted uses include residential (dwelling units, live/work, certain supportive and senior housing) plus mixed‑use, retail, and institutional categories as shown in the SUD’s Figure 3 use table; some uses are Island Conditional (IC) while others are permitted (P). Height and bulk are controlled by HT‑14 and the project’s Design for Development, and some areas are in the Tidelands Trust Overlay Zone with special jurisdictional rules (§ 249.52) .

What are the Treasure Island height and separation rules I must watch for?

The SUD relies on sectional HT maps (HT‑14) and implements Flex Height Zones (up to 450 ft in some areas) plus tower‑separation corridors and minimum clearances (e.g., 115 ft circular offsets and 500 ft corridors in identified blocks) — all defined in the SUD and its Design for Development (§ 249.52(e)(6)) .

Do overlays change parking requirements in the County?

Yes — many SUDs explicitly modify parking rules (examples: some HOPE SF SUDs report no minimum off‑street parking for certain non‑residential uses or caps on total parking). Always verify the overlay text for parking changes and consult the County Parking rules referenced in the SUD (see § 249.76(e)(5) and § 249.75) .

Do I need a special approval process or is the Planning Director authorized to act?

Overlay texts specify the review path. Some overlays delegate authority to the Planning Director for certain decisions or to other bodies (e.g., TIDA for tidelands), while others reserve decisions to the Planning Commission or require Conditional Use / Planned Unit Development approvals; check the SUD’s procedural divisions (e.g., § 249.52 and § 249.26) for who acts on applications (§ 249.52(e)(3)–(4)) .

How do I tell if my parcel is within an overlay map (SU / ZN / HT)?

Overlay applicability is map‑based. The SUD text references sectional maps (SU maps, ZN maps, HT maps) by name (for example, SU14, ZN14, HT14). To confirm parcel coverage, request the applicable Sectional Map from the Planning Department and compare your assessor parcel to the SUD maps (§ 249.52(e)(1)–(4)) .

Will an overlay stop me from using state‑required ADU rights?

The retrieved SUD texts did not include overlay‑specific ADU provisions in the materials reviewed (Not found in retrieved materials). ADU entitlements are governed by state ADU law plus any local implementing rules — verify with the jurisdiction and the overlay text whether the SUD imposes any additional constraints (Verify with the jurisdiction).

What is a Major Modification in an overlay like the San Francisco Gateway SUD?

A Major Modification is commonly defined as a deviation of 15% or more from any numeric or dimensional standard in the SUD/DSG; Minor Modifications are less than 15%. This classification affects process, findings, and public notice (§ 249.7(c)) .

Do overlays change sign rules?

Yes — some SUDs either adopt base Article 6 sign rules or establish special sign districts (e.g., Stonestown Special Sign District under § 608.10) that modify allowable signage and standards (§ 249.9; § 608.10) .

If my proposed project is inconsistent with an SUD, can I apply for exceptions?