Diamond Bar — Land Use

Last reviewed: July 2, 2026

Overview

This page summarizes how the City of Diamond Bar regulates land use under the local Development Code (Title 22). It explains how allowable uses are shown (P / MUP / CUP), the principal residential, commercial/industrial and special-purpose zoning districts, and the key development-standard sources an applicant must consult. The analysis is grounded in the City’s Title 22 Development Code (citations to the controlling § numbers are given) and interprets the application and interplay of the tables and chapters that control permitted and conditional uses.

How the Code organizes allowable uses (quick)

• Uses are listed in the zoning district tables and shown as P (permitted with zoning clearance), MUP (minor conditional use permit) or CUP (conditional use permit). See § 22.06.040 for the permit-symbol scheme and how to read the tables.
• The primary land-use tables referenced by the Code are Table 2‑2, Table 2‑3, Table 2‑4, Table 2‑7, and Table 2‑8 (residential, commercial/industrial, and special-purpose tables). See § 22.06.040 and the tables in articles II & III.

District-by-district breakdown

NOTE: Each district description below summarizes the Code’s stated purpose, typical permitted uses drawn from the district tables, and the key dimensional standards that the Code ties to that district. Verify parcel-specific rules with the Planning Department and the official zoning map (the Zoning Map is adopted and on file with the department). Verify with the jurisdiction for map boundary interpretations. § references are provided.

Residential districts (Article II — CHAPTER 22.08)

• RR (Rural Residential) — Purpose: hillside/rural living, allowing animal keeping and accessory structures; new subdivisions limited to 1 DU/acre or lower where hillside rules apply. See § 22.08.020(1) and Table 2‑4 for minimum lot sizes.

  • Typical permitted uses: single‑family dwellings (P), residential accessory structures (P), limited home occupations (P) — see residential tables and § references in Table 2‑4/2‑8.
  • Key standards: Minimum lot area: 1 acre (per Table 2‑4); setbacks and other standards referenced to article III (site planning).

• RL (Low Density Residential) — Purpose: existing detached single‑family neighborhoods; max 3 DU/gross acre for new subdivisions. See § 22.08.020(2) and Table 2‑4.

  • Typical permitted uses: single‑family dwellings (P), accessory uses and ADUs (subject to § 22.42.120), home occupations (P).
  • Key standards: Minimum lot area: 10,000 sq. ft. (Table 2‑4); setbacks measured according to § 22.16.090 (see development standards).

• RLM (Low/Medium Density Residential) — Purpose: lots with detached single-family dwellings; max 5 DU/gross acre. See § 22.08.020(3) and Table 2‑4.

• RM / RMH / RH / RH‑30 — These zones address multifamily densities:

  • RM — 12 DU/acre; RMH — 16 DU/acre; RH — 20 DU/acre; RH‑30 — up to 30 DU/acre (see Table 2‑4 and § 22.08.020(4–6)). Multifamily projects are regulated by the RH/RM standards and the Code’s site‑planning rules.
  • Typical permitted uses and special procedures: multifamily dwellings, parking and landscaping requirements in article III; affordable housing density bonus provisions in § 22.18.010 apply to projects meeting state density bonus criteria.

Where the residential tables are used to determine exact permitted symbols for specific uses, consult Tables 2‑3 and 2‑4 and the definitions in Article VI.

Commercial / Industrial districts (Article II — CHAPTER 22.10)

• C‑1 / C‑2 / C‑3 / CPD / C‑H / C‑R (various commercial zones) — Purpose: implement the general plan’s commercial categories and control intensity with FAR/dimensional standards. The Code maps existing Los Angeles County zoning to Development Code standards via Table 2‑2. See § 22.06.040 and Table 2‑2.

  • Typical permitted uses: retail, restaurants (may require CUP or MUP depending on district and use intensity), office/professional. Consult Table 2‑7 for the Commercial/Industrial District General Development Standards and the specific land‑use tables for permit symbols.

• OP / OB / CM / MPD / M‑1 / M‑1.5 (industrial / business park / manufacturing zones) — Purpose: employment and light‑industrial uses. Light manufacturing and similar uses are regulated by the industrial table and may be allowed or subject to CUP depending on operation size and impacts; refer to the land‑use tables and the definitions in Article VI. See Table 2‑2 mapping.

Key commercial/industrial development standards (height, minimum lot area where applicable, parking) are referenced to Table 2‑7 and article III standards (e.g., landscaping and parking). See § 22.10.040.

Special Purpose districts (SP, AG, OS, REC) — CHAPTER 22.12

• AG (Agriculture), OS (Open Space/Conservation), REC (Recreation) — Each has its list of allowed uses and permit requirements in Table 2‑8 (e.g., crop production and grazing, parks, schools, equestrian uses). The SP district standards may be set by an approved specific plan. See § 22.12.030 and Table 2‑8.

Overlay districts

• The City uses overlays for special rules; the Housing Element site (H) overlay is an example that allows multifamily dwellings on specific sites and adopts development standards of RH‑30 when multifamily is proposed. See § 22.14.050 for purpose, applicability, uses, and development standards.
• For a complete list of overlays and their map locations consult the official zoning map and the overlay chapter. The Code also incorporates non‑codified overlays shown on the zoning map. See § 22.14.040 and § 22.06.030(1–4).

Quick reference table — decision‑relevant excerpt

(These are representative excerpts — consult the complete Tables 2‑3 / 2‑5 / 2‑6 / 2‑8 for the full land‑use matrix; permit symbols are defined in § 22.06.040.)

How to read permit symbols and where approvals live

• P = permitted (zoning clearance required; see chapter 22.46). MUP = minor conditional use permit (chapter 22.56). CUP = conditional use permit (chapter 22.58). See § 22.06.040(c) and the permit‑key in the tables.
• Development review and implementation standards that commonly attach to land‑use approvals are in article III (site planning, landscaping, parking, signs, etc.) and chapter 22.48 (development review procedures). See § 22.02.020 and cross‑references in the tables.

(Links to the City’s procedural pages you will commonly need while preparing an application: Diamond Bar Zoning, Diamond Bar Development Standards, Diamond Bar Parking, Diamond Bar Design Review, Diamond Bar Overlay Districts, Diamond Bar ADUs. Also consult the statewide California Building Standards Code for building permit requirements once land‑use approval is obtained.)

Checklist — what an applicant must satisfy (high‑level)

• Confirm the parcel’s zoning and any overlays on the official City Zoning Map; resolve map boundary interpretation if parcel spans districts (see § 22.06.030 and § 22.06.040(d)).
• Determine the exact permit symbol for the proposed use in the applicable table (P / MUP / CUP in Table 2‑3 / 2‑5 / 2‑8) and follow that procedure. See § 22.06.040.
• Prepare site plans addressing the development standards in Table 2‑4 (residential) or Table 2‑7 (commercial/industrial) plus article III site planning standards (landscaping, parking, signs). See § 22.08.040 and § 22.10.040.
• If proposing an ADU, follow § 22.42.120 and state ADU law requirements. See § 22.42.120.
• If the use requires a MUP or CUP, prepare findings and CEQA documentation; minor CUP findings and conditions are in § 22.56.040–050; CUP process in § 22.58.010–030.
• Demonstrate site suitability for the use (access, utilities, compatibility) as required by the conditional findings and article II standards. See § 22.56.040(4–6) and § 22.02.020.
• Meet parking and loading requirements (chapter 22.30) and landscaping screening rules (chapter 22.24) and obtain required design review (chapter 22.48 when triggered).

Risks & Ambiguities

Plain‑English summary

Diamond Bar’s Development Code (Title 22) lists allowed land uses by zoning district in a set of tables, using P (permitted), MUP (minor CUP) and CUP symbols; residential zones (RR, RL, RLM, RM, RMH, RH, RH‑30) set densities and lot‑size minima (see Table 2‑4), commercial/industrial zones have their own standards (see Table 2‑7), and special overlays like the (H) overlay adjust rules for certain housing sites — you must check the Code’s district tables and the official zoning map to know what’s allowed on a parcel and which permit procedure applies.

Information Gaps (what I could NOT confirm from the retrieved materials)

• Complete verbatim contents of Table 2‑3 (the full land‑use matrix showing every use vs. every zoning district) were not fully extracted in the retrieved snippets; many table cells are present but the full table grid is not shown. Verify specific permit symbols for a particular use/district in the official Code or with Planning. Not found in retrieved materials.
• Exact numeric setback depths and height limits for each individual residential subzone beyond the Table 2‑4 summary references are not fully enumerated in the snippets; the Code cross‑references § 22.16.090 and other sections for measurement. Verify numeric setbacks and projections with the official Code text and § 22.16.090. Not found in retrieved materials.
• Updated zoning map parcel‑specific overlays and any non‑codified overlay details (the zoning map is “on file” with the Department) — parcel‑level overlay applicability must be checked on the official map. Not found in retrieved materials.

Source References

• Diamond Bar Development Code (Title 22 — Development Code), Title and purpose; see § 22.01.010–040.
• Zoning district regulations and permit symbols: § 22.06.040 (uses listed as P, MUP, CUP; tables referenced).
• Residential district purposes and Table 2‑4 (residential general development standards): § 22.08.020 and § 22.08.040 (Table 2‑4).
• Commercial/Industrial general standards and Table 2‑7: § 22.10.040.
• Special purpose districts and Table 2‑8 (allowed uses): § 22.12.030 and Table 2‑8.
• Housing‑element overlay (H) — purpose, applicability, uses, and standards: § 22.14.050.
• Permit procedures: zoning clearance (chapter 22.46), minor CUP (chapter 22.56), CUP (chapter 22.58); findings and conditions references appear in those chapters (see § 22.56.040–050 and § 22.58.010–030).
• ADU provisions: § 22.42.120 (accessory dwelling units/JADUs).
• Source record: Title 22 print export (library.municode.com) as the source of the Development Code text used for this analysis.

Retrieved passages

• CBC § 2 (§ 2) High relevance show source text
• Diamond Bar Zoning Code (§ 2) High relevance show source text
• Diamond Bar Zoning Code (chapter 22.56) High relevance show source text
• Diamond Bar Zoning Code (§ 2) High relevance show source text
• Diamond Bar Zoning Code (§ 2) High relevance show source text
• Diamond Bar Zoning Code (title 7) High relevance show source text
• Diamond Bar Zoning Code (§ 2) High relevance show source text
• Diamond Bar Zoning Code (chapter 22.62) High relevance show source text

Cited sections

• Diamond Bar Development Code (Title 22 — Development Code), Title and purpose; see **§ 22.01.010–040**. (Title 22)
• Zoning district regulations and permit symbols: **§ 22.06.040** (uses listed as P, MUP, CUP; tables referenced). (§ 22.06.040)
• Residential district purposes and Table **2‑4** (residential general development standards): **§ 22.08.020** and **§ 22.08.040** (Table 2‑4). (§ 22.08.020)
• Commercial/Industrial general standards and Table **2‑7**: **§ 22.10.040**. (§ 22.10.040)
• Special purpose districts and Table **2‑8** (allowed uses): **§ 22.12.030** and Table **2‑8**. (§ 22.12.030)
• Housing‑element overlay (H) — purpose, applicability, uses, and standards: **§ 22.14.050**. (§ 22.14.050)
• Permit procedures: zoning clearance (chapter **22.46**), minor CUP (chapter **22.56**), CUP (chapter **22.58**); findings and conditions references appear in those chapters (see **§ 22.56.040–050** and **§ 22.58.010–030**). (§ 22.56.040)
• ADU provisions: **§ 22.42.120** (accessory dwelling units/JADUs). (§ 22.42.120)
• Source record: Title 22 print export (library.municode.com) as the source of the Development Code text used for this analysis. (Title 22)
• DiamondBar_ZoningCode.md

• Official Diamond Bar code library