Santa Rosa · Land use · Duplex
Where is a duplex allowed in Santa Rosa?
In Santa Rosa, a duplex is allowed in 13 base zones (RR, R-1, R-2, R-3, TV-R and 8 more, all with a condition), needs a permit in 3 (CO, BP and OSR, all with a condition) and not allowed in 6 (Santa Rosa use tables, read October 2026).
Key points
- Allowed: RR, R-1, R-2, R-3, TV-R, CN, CG, CMU and 5 more
- Needs a permit: CO, BP and OSR
- Not allowed: MH, CV, IL, IG, OSC and PI
Find your lot's zone on the city zoning map, then read its row. Every status below was read from the Santa Rosa Municipal Code use tables (read October 2026). Base zones only. General information, not legal advice — check with the city before you apply.
Zones where a duplex can go
Santa Rosa's code calls this use “Duplex”. Each row links to the use table it comes from. A zone marked “see note” has a condition in the code, for example upper floors only or a larger lot.
| Zone | Status | Code |
|---|---|---|
| RR Rural Residential | Allowed — see note Note 3: Permitted by right within any residential Planned Development. | § 20-22.030 |
| R-1 Single-Family Residential | Allowed — see note Note 3: Permitted by right within any residential Planned Development. | § 20-22.030 |
| R-2 Medium Density Multi-Family Residential | Allowed — see note Note 3: Permitted by right within any residential Planned Development. | § 20-22.030 |
| R-3 Multi-Family Residential | Allowed — see note Note 3: Permitted by right within any residential Planned Development. | § 20-22.030 |
| TV-R Transit Village-Residential | Allowed — see note Note 3: Permitted by right within any residential Planned Development. | § 20-22.030 |
| CN Neighborhood Commercial | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. Note 7: Residential uses are encouraged as part of new development on sites zoned CN, as described in Section 20-23.050 . | § 20-23.030 |
| CG General Commercial | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| CMU Core Mixed Use | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| SMU Station Mixed Use | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| MMU Maker Mixed Use | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| NMU Neighborhood Mixed Use | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| CSC Community Shopping Center | Allowed — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. Note 2: Each new development or project involving significant additions or reconstruction is required to be a mixed use project with a residential component in compliance with the residential density requirements for the CSC zoning district as described in Sections 20-23.040 and 20-23.080 . | § 20-23.030 |
| TV-M Transit Village-Mixed | Allowed — see note Note 5: Uses permitted on upper stories of building, Director Use Permit required when proposed on ground floor. Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| CO Office Commercial | Needs a director conditional use permit — see note Note 13: Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Note 16: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within one of the City's Priority Development Areas. | § 20-23.030 |
| BP Business Park | Needs a director conditional use permit — see note Note 4: Use only allowed if ancillary and related to a primary or dominant use. Note 9: Permitted with a Director Conditional Use Permit within any of the City's Priority Development Areas. Note 10: Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within any of the City's Priority Development Areas. | § 20-24.030 |
| OSR Open-Recreation | Needs a minor conditional use permit — see note Note 3: Not permitted in the Southeast Greenway area. | § 20-26.030 |
Zones where it is not allowed
What else applies
- Separate row 'Half-Plex': S3 P in all six residential zones (incl. MH); S4 CO MUP, CN/CG/CMU/SMU/MMU/NMU/CSC P, CV -, TV-M P (5). Not used.
- State law: SB 9 (Gov. Code § 65852.21) allows two homes on most single-family lots with a ministerial permit, also where this table says no.
- Not covered here: Planned Development (PD) zones, specific plan areas and combining districts (e.g. -SH Senior Housing, 20-28.080) are not in the packet. Several notes give different rights inside Planned Developments and Priority Development Areas; these are carried in the notes but not decided here.; Division 7 land-use definitions, 20-42.040 (animal keeping), 20-42.190 (emergency shelter), 20-42.230, 20-42.050, 20-42.080, 20-42.164 are cited by the tables but NOT in the packet.. Overlay zones and specific plans can also change the answer.
Other uses in Santa Rosa
Who this affects
HomeownersBuyersReal estate agentsSmall developers
Frequently asked questions
Can I have a duplex in the CO zone in Santa Rosa?
Only with a director conditional use permit. Santa Rosa's use table lists it that way in CO (Office Commercial) (§ 20-23.030). The code adds a condition: “Permitted by right within any commercial Planned Development within one of the City's Priority Development Areas. Permitted with a Director Conditional Use Permit within any nonresidential Planned Development within…”
Can I have a duplex in the MH zone in Santa Rosa?
No. Santa Rosa's use table does not allow it in MH (Mobile Home Park) (§ 20-22.030).
Can I have a duplex in the RR zone in Santa Rosa?
Yes, with a condition. Santa Rosa's use table lists it as allowed in RR (Rural Residential) (§ 20-22.030). The code adds a condition: “Permitted by right within any residential Planned Development.”
General information, not legal advice.
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