Suisun City — Development Standards

Last reviewed: July 2, 2026

Overview

This page summarizes the Suisun City zoning ordinance rules that control setbacks, height, lot coverage, and basic intensity (density / FAR) — the development standards that determine how big and where you may build on a parcel. It pulls the controlling local code tables and explanatory notes so you can compare the RL, RM, CR, CMU, and other districts side‑by‑side and spot ADU and parking exceptions. For background on how these requirements fit into broader planning and approvals see the Suisun City zoning & planning overview and consult the city’s rules on parking, design review, overlay districts, and ADUs; building‑code issues belong to the California Building Standards Code.

Note: every numeric rule below is taken directly from the Suisun City Municipal Code tables and chapter notes cited with the controlling §; verify parcel‑specific constraints with the jurisdiction.

District-by-district development standards

The city’s zoning districts are established in § 18.06.010 (district list).

Below I summarize the most decision‑relevant development standards from the ordinance tables (setbacks, height, lot coverage, and any published FAR/density ranges). For each district I cite the municipal code section that contains the development table or the district purpose language.

RL — Low‑Density Residential

• Purpose / typical uses: single‑family detached and other low‑density housing consistent with the low‑density general plan designation; see § 18.06.010 and residential standards.
• Key dimensional standards (Table 18.31.01 / § 18.31.005): Minimum lot area 3,600 sq ft, maximum lot coverage 40%, front setback 10 ft min / 20 ft max, side (interior) 5 ft min, rear 10 ft, maximum height 35 ft. All numbers are from § 18.31.005.
• Where it applies: primarily single‑family neighborhoods mapped on the city zoning map; see § 18.06.020.

RM — Medium‑Density Residential

• Purpose / typical uses: smaller‑lot single family, duplexes, and low‑rise multi‑family; see § 18.31 (residential standards).
• Key dimensional standards (Table 18.31.01 / § 18.31.005): Minimum lot area 1,800 sq ft, maximum lot coverage 80%, front setback 10 ft min / 20 ft max, side 0–5 ft (interior), rear 5 ft, maximum height 35 ft. § 18.31.005 lists accessory‑dwelling specific setbacks (4 ft side/rear) and other ADU notes.

RH1 / RH2 — High‑Density Residential 1 & 2

• Purpose / typical uses: multifamily housing forms (townhomes, apartments, flexible multi‑family) and higher intensity residential development; see § 18.31 and § 18.30.120.
• Key dimensional standards (Table 18.31.01 / § 18.31.005): Minimum lot area RH1 1,200 sq ft / RH2 800 sq ft, maximum coverage 80%, front setback 0–15 ft, side 0–5 ft, rear 5 ft, maximum height RH1 = 55 ft / RH2 = 55 ft.
• Usable open space requirements are described in § 18.31.010–.020 for RM/RH/RMU.

RMU — Residential Mixed‑Use

• Purpose / typical uses: vertical mixed use and live/work where residential can sit above or behind ground‑floor commercial (residential not required, when present is often 10–40 du/ac ranges in CMU/related zones). See § 18.22 (CMU purpose) and § 18.20 tables for densities. § 18.22.010 describes CMU intent that parallels RMU mixed‑use aims.
• Key dimensional standards (Table 18.31.01 / § 18.31.005): minimum lot area 800 sq ft, maximum lot coverage 80%, front setback 0–15 ft, side 0–5 ft, rear 5 ft, maximum height 55 ft. ADU rules discussed below also apply.

CR — Commercial Retail

• Purpose / typical uses: retail sale of goods and services (large and neighborhood retail); see § 18.20.010.
• Key dimensional standards (Table 18.32.01 / § 18.32.010): minimum lot area 2,400 sq ft, maximum lot coverage 100%, front setback 0 ft, side (interior) 0 ft, rear 10 ft, maximum height 45 ft / 3 stories. § 18.32.010 provides the full table.
• Intensity / FAR: the CR zone has a nonresidential FAR range of 0.25–1.0 (Table 18.20.01 / § 18.20.060).

CSF — Commercial Services & Fabricating

• Purpose / typical uses: mix of retail, services, warehousing, light assembly; see § 18.20.020.
• Key dimensional standards (Table 18.32.01 / § 18.32.010): minimum lot area 7,500 sq ft, maximum lot coverage 80%, front setback 10 ft, side adjacent to residential 20 ft, rear 10 ft, maximum height 45 ft / 3 stories.
• Intensity / FAR: FAR 0.25–0.5 for CSF.

CMU — Commercial Mixed‑Use

• Purpose / typical uses: ground‑floor commercial with residential above; the CMU purpose and allowed residential intensity are set out in § 18.22 and § 18.20.030. Residential (when built) is expected in the 10–40 du/acre range and nonresidential FAR 0.25–1.0.
• Key dimensional standards (Table 18.32.01 / § 18.32.010): minimum lot area 2,500 sq ft, maximum lot coverage 100%, front setback 0–10 ft, side 0–10 ft, rear 15 ft min, maximum height 45 ft / 3 stories.

O — Business & Professional Office

• Purpose / typical uses: professional offices and complementary services; see § 18.20.040.
• Key dimensional standards (Table 18.32.01 / § 18.32.010): minimum lot area 2,500 sq ft, maximum coverage 80%, front setback 0–10 ft, side 0–10 ft, rear 10 ft, maximum height 45 ft / 3 stories.
• Intensity / FAR: FAR 0.25–1.0 (Table 18.20.01 / § 18.20.060).

P, OS, APS, PQP, PUD, DWSP (park / public / special plan)

• Civic/park/other zones have their own table (Table 18.33.01 under § 18.33.010) that sets minimum lot sizes, lot coverage (often 40%–80%), setbacks and lower building heights where adjacent to residential; specific heights, setbacks, and uses vary by the APS / P / PQP designation.
• The DWSP (Waterfront District Specific Plan) is regulated by the adopted waterfront specific plan; parcels in DWSP follow the specific plan rather than the general commercial density table. See § 18.20.050.

Quick decision table (most‑used standards)

(See each cited table for full side/corner setbacks, accessory‑structure rules and ADU notes; accessory and ADU specifics are called out in Table 18.31.01 notes and in § 18.30.170. )

Special topics and notes (practical guidance)

• Accessory dwelling units (ADUs): Suisun City’s ADU rules and the table notes allow 4 ft side/rear setbacks for new ADUs and set other ADU clarifications; internal and converted ADUs have separate allowances (see notes to Table 18.31.01 and § 18.30.170 H–J). Always check both the city ADU rules and state ADU law. § 18.31.005 and § 18.30.170 contain the local ADU references.

  • Practical: an ADU on a small RL lot can generally be built to 4 ft side/rear setbacks and the ordinance lists specific size/height caps and exceptions in the table notes — verify whether your parcel sits in DWSP or an overlay that adds constraints.
  • See the city ADU resource at the Suisun City ADU page for application process steps. ADUs

• Parking: Off‑street parking standards and reductions are in Chapter § 18.42 (parking chapter) and the CR/CMU table references parking chapter for required spaces; shared‑parking rules and maximums for some nonresidential uses are spelled out in Chapter 18.42. Plan parking with the parking table and coordinate with the planning division early. parking

• Fences & walls: Residential side/rear fences behind the front setback are limited to 6 ft; front fences in RL/RM have lower limits (3 ft solid / 4 ft if >50% open). See § 18.34.010 (Table 18.34.01).

• Height exceptions & projections: Chimneys, vents, and required flues may extend above a district height where necessary for safety subject to the development services director’s approval (§ 18.38.010). Roof‑pitch allowances and CUP exceptions for height in certain zones are noted in table footnotes.

• Design review & site design: Many commercial and multi‑family projects must demonstrate pedestrian amenities, street trees, and site design consistency (see § 18.14.050 and related chapters). Early design‑review consultation is recommended; see the city’s design review page.

• Overlays / specific plans: Parcels within the DWSP (Waterfront District Specific Plan) follow the specific plan and not the baseline commercial density table; always check the DWSP map and overlay provisions (§ 18.20.050). overlay districts

Checklist (what an applicant must satisfy up front)

• Confirm zoning district and any overlays / special plan status for the parcel (DWSP or other) — § 18.06.010 / § 18.20.050.
• Run the project against the district development table (setbacks, lot coverage, height) in § 18.31.005 (residential) or § 18.32.010 (commercial).
• Determine required parking and any allowable reductions in § 18.42 and Table 18.42.02.
• Check ADU-specific notes and limits (accessory building location, ADU setbacks/height exceptions) in Table 18.31.01 notes and § 18.30.170.
• Confirm fence/wall heights and landscape front‑yard requirements in § 18.34 and site‑landscape rules.
• If applicable, prepare materials showing consistency with the City’s design guidelines and submit per the design review process. design review

Risks & Ambiguities

Plain‑English summary

Suisun City’s zoning tables spell out the exact front/side/rear setbacks, lot coverage limits, and maximum building heights by district (for example, RL = 35 ft high, 40% lot coverage; CR/CMU commercial allows 0–10 ft front setbacks and up to 45 ft / 3 stories), while ADUs and specific plans (DWSP) carry special notes and exceptions you must check in the cited sections. See the code tables in § 18.31.005 (residential) and § 18.32.010 (commercial) for the numeric rules and the specific plan/overlay sections for overrides.

Source References

• Suisun City Municipal Code — Zoning Districts and Definitions: § 18.06.010 (zoning districts).
• Suisun City Municipal Code — Development standards, residential zones (Table 18.31.01): § 18.31.005.
• Suisun City Municipal Code — Development standards, commercial zones (Table 18.32.01): § 18.32.010.
• Suisun City Municipal Code — CMU purpose and densities / Table 18.20.01: § 18.20.030 and § 18.20.060.
• Suisun City Municipal Code — Civic / park development standards (Table 18.33.01): § 18.33.010.
• Suisun City Municipal Code — ADU notes and references (Table notes & § 18.30.170). § 18.30.170 (ADU‑related notes referenced in tables).
• Suisun City Municipal Code — Fences and walls: § 18.34.010 (Table 18.34.01).
• Suisun City Municipal Code — Parking and loading: § 18.42.010 and parking tables (e.g., Table 18.42.02).
• Suisun City Municipal Code — DWSP (Waterfront District Specific Plan): § 18.20.050.

If you want the ordinance PDF pages or the exact table images extracted into a printable one‑page checklist, tell me which parcel or parcel APN you’re working with and I’ll map the district and pull the exact line items for that parcel (Verify with the jurisdiction for any site‑specific exceptions).

Retrieved passages

• Suisun City Zoning Code (Chapter 18.42) High relevance show source text
• CBC § 66314 (§ 66314) High relevance show source text
• Suisun City Zoning Code (Section 21155) High relevance show source text
• Suisun City Zoning Code (§ 66317) High relevance show source text
• Suisun City Zoning Code (§ 3) High relevance show source text
• CBC § 3 (§ 3) High relevance show source text
• Suisun City Zoning Code (§ 3) High relevance show source text
• CBC § 51178 (Section 51178) High relevance show source text
• Suisun City Zoning Code (§ 3) High relevance show source text
• Suisun City Zoning Code (Chapter 18.36) Medium relevance show source text
• Suisun City Zoning Code (§ 66314) Medium relevance show source text
• Suisun City Zoning Code (Section 18.32.) Medium relevance show source text
• Suisun City Zoning Code (§ 3) Medium relevance show source text
• Suisun City Zoning Code (section 18.30.170) Medium relevance show source text

Cited sections

• Suisun City Municipal Code — Zoning Districts and Definitions: **§ 18.06.010** (zoning districts). (§ 18.06.010)
• Suisun City Municipal Code — Development standards, residential zones (Table 18.31.01): **§ 18.31.005**. (§ 18.31.005)
• Suisun City Municipal Code — Development standards, commercial zones (Table 18.32.01): **§ 18.32.010**. (§ 18.32.010)
• Suisun City Municipal Code — CMU purpose and densities / Table 18.20.01: **§ 18.20.030** and **§ 18.20.060**. (§ 18.20.030)
• Suisun City Municipal Code — Civic / park development standards (Table 18.33.01): **§ 18.33.010**. (§ 18.33.010)
• Suisun City Municipal Code — ADU notes and references (Table notes & § 18.30.170). **§ 18.30.170** (ADU‑related notes referenced in tables). (§ 18.30.170)
• Suisun City Municipal Code — Fences and walls: **§ 18.34.010** (Table 18.34.01). (§ 18.34.010)
• Suisun City Municipal Code — Parking and loading: **§ 18.42.010** and parking tables (e.g., Table 18.42.02). (§ 18.42.010)
• Suisun City Municipal Code — DWSP (Waterfront District Specific Plan): **§ 18.20.050**. (§ 18.20.050)
• SuisunCity_ZoningCode.md

• Official Suisun City code library