Commerce — Overlay Districts

Last reviewed: July 1, 2026

Overview

Commerce uses several overlay zones and special plan chapters inside Title 19 - ZONING to modify or expand the base zone rules for specific properties. Key overlays in the code are the Planned Development Overlay (PD), the Housing Opportunity Overlay (HOO), the Modelo Specific Plan (MSP) / specific plans, and the city's historic landmark/district provisions — each is established inside Title 19 and mapped on the official zoning map. The overlays change permitted uses, dimensional rules, or procedures while preserving the underlying base-zone framework unless the overlay expressly supersedes it. See the city's general zoning summary in the Commerce zoning & planning overview for context. § 19.01.010

Note: throughout this page I link the Commerce topics you will most commonly need:

• development rules and numeric standards are discussed in Commerce Development Standards,
• parking requirements are in Commerce Parking,
• design review requirements are administered under Commerce Design Review,
• ADU policy is separate under Commerce ADUs, and
• the state's construction standards live under California Building Standards Code.
  I also reference rules for nonconforming properties and remedies under Commerce Nonconforming Uses and Variances and Exceptions where procedural relief is available.

How Commerce defines overlays (quick legal points)

• Overlays in Commerce are implemented inside Title 19 and used "only in conjunction with an underlying zone district" unless otherwise stated. This explicit overlay model is stated for the PD overlay (§ 19.15.010) and the HOO overlay (§ 19.47.010 - § 19.47.020) .
• The official zoning map identifies which parcels are inside overlays; where boundaries are unclear the planning commission has authority to interpret boundaries. § 19.05.020 and boundary rules § 19.05.030 .

District-by-district breakdown

Planned Development Overlay (PD)

• Purpose: The PD overlay encourages creative land‑use design and allows flexibility in layout and standards while requiring a comprehensive plan for the development. § 19.15.010 .
• Where it applies: Applied only in conjunction with an underlying zone (PD is not a stand‑alone zone). § 19.15.010(A) .
• Typical permitted uses: The PD requires that at least 60% of the lot be developed with one or more of the principally permitted uses of the underlying zone. Uses not listed may be allowed if the planning commission finds them similar and not more detrimental than listed uses. § 19.15.020(A–C) .
• Key procedural and submission requirements:
  • Minimum project area: 40,000 sq ft minimum total development site for PD applications. § 19.15.030(A) .
  • Required approvals: PD developments require a zone change and a conditional use permit (CUP). § 19.15.040(A) .
  • Submittals: a master plan (site plan, landscape, elevations), a traffic management plan, and, for commercial/industrial PDs, a master sign plan. § 19.15.030(B) and § 19.15.040(B–D) .
• How PD modifies standards: The PD can vary development standards from the underlying zone so long as it complies with open space, landscaping, parking, and loading requirements of the underlying zone (i.e., some standards remain anchored to the base zone). § 19.15.040(E) .
• Practical guidance: Expect full discretionary review (public hearings before planning commission and likely city council), and prepare a full master plan and traffic study. Confirm required open‑space, landscaping, and parking numbers with Commerce Development Standards and Commerce Parking before filing. § 19.15.030–040

Housing Opportunity Overlay (HOO)

• Purpose: The HOO is expressly intended to facilitate "by‑right" residential and mixed‑use redevelopment of underutilized heavy‑manufacturing (M‑2) parcels identified as housing opportunity sites; it implements part of the housing element. § 19.47.010(A–B) .
• Applicability & relationship to base zone:
  • The HOO is applied only in conjunction with the M‑2 (Heavy Manufacturing) base zone and covers a defined area (Rosewood Planning Area — boundaries described in § 19.47.020(A)). § 19.47.020(A–C) .
  • Properties may continue to develop under the base zone; the HOO does not automatically override the base zone unless the owner elects to develop under the HOO standards. § 19.47.020(C–D) .
• Permitted uses: All uses allowed in the underlying zone remain allowed; the HOO then lists additional residential and mixed‑use allowances. Conversion of existing nonresidential structures to residential may require a CUP. § 19.47.030(A, E) .
• Key dimensional / design standards (summary pulled from Table 19.11.040A — the HOO development table):
  • Maximum residential density: 40 du/acre.
  • Maximum nonresidential intensity: 1.0 FAR (podium/underground parking excluded from FAR).
  • Maximum height: 5 stories / 60 ft (height measured from grade).
  • Setbacks: Front and street side 0 ft (min) / 15 ft (max); interior side 5 ft min (10 ft min if abutting residential); rear yard 10 ft min for residential portion.
  • Minimum separation between buildings: 10 ft (with increases for greater height).
  • Private open space standards and publicly accessible open space percentages exist in the table. See Table 19.11.040A for full numeric standards. § 19.47.040 and Table 19.11.040A .
• Process & effects: Owners may choose to develop under the HOO standards; once a property is developed under HOO, the HOO provisions supersede the base zone standards for that property. § 19.47.020(D, F) .
• Practical guidance: If you own or are negotiating an M‑2 parcel in the Rosewood area, the HOO can substantially relax setbacks and increase density/height — but you must elect the HOO pathway and meet the HOO submittal and design requirements. Check parking and open‑space obligations in Commerce Parking and Commerce Development Standards early in design. § 19.47.020–040

Modelo Specific Plan (MSP) / Specific Plans

• Legal basis: Commerce lists specific plans under Chapter 19.16. The Modelo Specific Plan is adopted by reference; where the specific plan contains different development standards (height, density, parking, signs, etc.) that plan prevails over the code. § 19.16.010–020 .
• Practical guidance: For parcels inside the Modelo Specific Plan (MSP) the MSP text and maps are the controlling document for many dimensional and use items — always use the MSP document together with Title 19. § 19.16.020 .

Historic Landmark / Historic District provisions

• Authority & purpose: Commerce created a chapter addressing historic landmarks/districts (Chapter 19.17) to protect cultural resources; the chapter establishes intent and procedures for landmark/district designation and review. § 19.17.010 .
• Practical note: Historic designation triggers the Cultural Resource Management Commission review and special permit/review paths in the administration chapters; the code cross‑references landmark/district alteration permits and appeals. Detailed alteration and review standards are in Chapter 19.17 and the Division tables for hearing bodies. § 19.17.010 and Table 19.39.020A .
• What I could not confirm in the retrieved materials: Specific alteration standards, demolition restrictions, or district design guidelines (if they exist) are not present in the retrieved snippets. Verify with the jurisdiction and the full Chapter 19.17 text. Not found in retrieved materials. Verify with the jurisdiction.

Quick reference table — decision‑relevant overlay items

Information gaps (items not confirmed in the retrieved files)

• Whether accessory dwelling units (ADUs) have special treatment inside HOO or PD overlays: Not found in retrieved materials — confirm with Commerce ADUs and the Community Development Director. Not found in retrieved materials.
• Full text of Chapter 19.17 (Historic standards and demolition/alteration rules) — snippets show intent but not standards or process steps. Verify with full Chapter 19.17. Not found in retrieved materials.
• Exact map figures and parcel lists for HOO and MSP (figure captions are shown but the maps themselves were omitted from the extract). Confirm with the Official Zoning Map on file at the city clerk. § 19.05.020

Checklist — what an applicant must satisfy (overlay filings)

• Confirm whether the parcel is inside an overlay on the Official Zoning Map and which overlay applies. § 19.05.020
• For PD: assemble a master plan package with site plan, elevations, landscape plan, traffic management plan, and a master sign plan if commercial/industrial; prepare to file for a zone change and CUP. § 19.15.030–040
• For HOO: elect the HOO development path (owner option); confirm compliance with Table 19.11.040A (density, FAR, height, setbacks, open space) and parking obligations. § 19.47.020–040
• Confirm required public notices and hearings (PD and many HOO conversions will be discretionary). See hearing body table for which body acts. Table 19.39.020A.
• Check nonconforming-use rules if the site has existing industrial uses and is converting; review Chapter 19.37 (Nonconforming Uses). § 19.47.020(C)
• Coordinate with Commerce Parking and Commerce Development Standards to size parking, loading, landscaping, and open space; expect those chapters to apply unless the overlay explicitly supersedes them. § 19.15.040(E)

Risks & Ambiguities

Plain-English Summary

Commerce's overlays (notably the PD and HOO) are special zoning layers that let owners do projects different from the base zone — the PD is a discretionary, design‑oriented tool requiring a master plan and CUP/zone change, while the HOO is a targeted overlay letting certain M‑2 sites convert to higher‑density housing if the owner opts in and meets the HOO table standards. Where a specific plan (Modelo) applies, that plan's rules often replace Title 19 numbers. Check the Official Zoning Map and talk to the planning department early. § 19.15.010; § 19.47.020; § 19.16.020

Source References

• Commerce Title 19 — Zoning (print export). Key chapters cited in this page: Chapter 19.15 (Planned Development Overlay) § 19.15.010–040.
• Commerce Title 19 — Zoning. Chapter 19.47 (Housing Opportunity Overlay Zone) § 19.47.010–040 and Table 19.11.040A.
• Commerce Title 19 — Zoning. Chapter 19.16 (Specific Plans) and Modelo Specific Plan incorporation § 19.16.010–020.
• Commerce Title 19 — Zoning. Chapter 19.17 (Historic Landmark/District) intent and cross references § 19.17.010.
• Commerce Title 19 — Official Zoning Map and zones established (§ 19.05.020; zones list including PD and MSP).
• Administrative procedures and hearing bodies (Table 19.39.020A).

Retrieved passages

• Commerce Zoning Code (§ 1) High relevance show source text
• Commerce Zoning Code (§ 1) Medium relevance show source text
• Commerce Zoning Code (§ 1) Medium relevance show source text
• Commerce Zoning Code (§ 1) Medium relevance show source text
• Commerce Zoning Code (§ 4) Medium relevance show source text
• Commerce Zoning Code (Chapter 19.19.) Medium relevance show source text
• Commerce Zoning Code (§ 1) Medium relevance show source text
• Commerce Zoning Code (Section 65906) Medium relevance show source text

Cited sections

• Commerce Title 19 — Zoning (print export). Key chapters cited in this page: **Chapter 19.15 (Planned Development Overlay)** **§ 19.15.010–040**. (Title 19)
• Commerce Title 19 — Zoning. **Chapter 19.47 (Housing Opportunity Overlay Zone)** **§ 19.47.010–040** and Table 19.11.040A. (Title 19)
• Commerce Title 19 — Zoning. **Chapter 19.16 (Specific Plans)** and Modelo Specific Plan incorporation **§ 19.16.010–020**. (Title 19)
• Commerce Title 19 — Zoning. **Chapter 19.17 (Historic Landmark/District)** intent and cross references **§ 19.17.010**. (Title 19)
• Commerce Title 19 — Official Zoning Map and zones established (**§ 19.05.020**; zones list including PD and MSP). (Title 19)
• Administrative procedures and hearing bodies (Table 19.39.020A).
• Commerce_ZoningCode.md

• Official Commerce code library