Senate Bill 9 (SB9) Information and FAQ

Senate Bill 9 (SB 9) 

Senate Bill 9 (SB 9) aims to streamline housing production. Effective January 1, 2022, SB 9 requires all local jurisdictions to *ministerially review up to two residential units on a parcel in a single-family residential zone if the project meets specific objective standards. It also requires jurisdictions to provide ministerial review of a subdivision of one lot into two lots in a single-family residential zone if specific objective standards are met. 

*“Ministerial" means a project must be approved if it complies with objective standards, without any subjective judgment from planners. Ministerial projects are not subject to environmental reviews or public hearings.   

Does my property qualify for an SB 9 project? 

  • The property must comply with all requirements listed below to qualify as an SB 9 project. The parcel must be zoned for single-family residential use RR, R1, R2 or any planned unit development (PUD) that permits single-family dwellings only. (Verify the zoning of a parcel in Petaluma here.) 
  • The proposed project cannot be located within a Historic District. (Verify here.)    
  • The proposed project cannot be located on a property in any of the following areas:  
    • Prime farmland  
    • Wetlands as defined under federal law 
    • Hazardous waste site  
    • Protected species habitat  
    • Lands under a conservation easement  
    • Lands identified for conservation in an adopted natural community conservation plan, habitat conservation plan or other adopted natural resource protection plan  
    • A site containing a historic landmark (Local landmarks can be viewed here)


  • If the parcel is located within the Very High Fire Severity Zone (VHFSZ), it must comply with applicable building standards and state fire mitigation measures. (Verify if your property is in the VHFSZ here.)   
  • If the parcel is located in a special flood hazard area subject to induction by the 1 percent annual chance flood (100-year flood) or regulatory floodway as determined by FEMA (Verify here), the project must meet applicable federal criteria.  
  • If the parcel is located within an earthquake fault zone (Verify here), the project must comply with applicable seismic protection building code standards. 

The project must also comply with City Objective Design and Subdivision Standards as provided in applicable checklists, provided that each lot size is a minimum of 1,200 sf, a minimum of 40% of the original lot and development on each lot contains no more than two primary dwelling units of at least 800 sf each, with setbacks of at least four feet from the rear and side property lines (or none if in an existing structure or new structure built to the same dimensions) 

How do I apply for an SB 9 unit? 

First download and complete an SB 9 Two-Unit Development Checklist and review Building Submittal Requirements here. When ready, submit your application for a Residential - Single Family (if new SB9 unit(s) will be detached) or Residential Multi Family (if SB9 unit(s) will be attached i.e., duplex) through the Permits & Planning Applications Hub. We strongly recommend discussing your potential SB 9 project with a planner before you submit your application. Schedule a 15-minute appointment to speak with a planner here.  

How do I apply for an SB 9 Urban Lot Split? 

Review the SB 9 Urban Lot Split Checklist and Submittal Requirements and submit your application for a Tentative Parcel Map through the Permits & Planning Applications Hub. We strongly recommend discussing your potential SB 9 project with a planner before you submit your application. Schedule a 15-minute appointment to speak with a planner here. 

Frequently Asked Questions (FAQs)

No, an SB 9 unit is not the same as an Accessory Dwelling Unit (ADU). See the ADU webpage for more information regarding ADU requirements. SB 9 units are primary dwelling units and must provide for separate utility connections and pay full impact fees. 

The following project types in a single-family residential zoning district qualify if all eligibility requirements are met: 

SB 9 Lot Split 

  • The creation of a new parcel (lot split of an existing residential parcel) 
    • Two primary dwelling unit may be located on each newly created lot 

SB 9 Unit 

  • On a vacant parcel 
    • The construction of up to two new detached single-family home 
    • The construction of two attached single-family homes (duplex) 
  • On a parcel with an existing home 
    • The construction of an additional attached or detached primary dwelling  

An SB 9 lot split is when an existing legal lot is subdivided into two legal lots. Each lot must be at least 40 percent of the original lot’s size, or at least 1,200 square feet, whichever is greater. The new lots must comply with objective subdivision standards such as providing access to or adjoin the public right-of-way and provide for separate utilities. 

An SB 9 two-unit development is when a project proposes to add one new primary dwelling unit on a lot with an existing single-family dwelling or create up to two new dwelling units on a vacant lot. The units can be attached (duplex) or detached. An ADU and JADU may also be permitted in accordance with the City’s ADU Ordinance 

  • Urban Lot Split (Tentative Parcel Map) $4,265.17 deposit + Staff Time & Materials (Applicant will be billed for the full cost of processing the application) See Fee Schedule 
  • Two-Unit Development – Building permits are based on how much the project will cost to complete (also known as the project valuation). Development Impact Fees for a new single-family or multi-family dwelling is also required.  

Pursuant to state law, SB 9 is a ministerial review so there is no neighbor notification and no public hearings.

Yes, if an SB 9 lot split is proposed the owner must occupy one of the dwelling units of a minimum of 3 years from the date of the approval of the SB 9 land division unless the applicant is a community land trust or a qualified nonprofit corporation. If the project is only for an SB 9 dwelling unit (no lot split) the owner is not required to live on the property.  

No, state law prohibits SB 9 units to be used as short-term rentals. Short-term rentals are rentals for overnight lodging of less than 30 days. Long-term rentals (30 days or greater) are not regulated by SB 9.

Perhaps but only if the PUD exclusively allows single-family residence and no CC&R restrictions are in place. Check with a Planner if unsure.

Yes, you may apply for an SB 9 Lot Split and submit for an SB 9 Unit application concurrently

Questions or Comments?

Please review the Frequently Asked Questions (FAQs) below to see if the answer to your question is listed. Otherwise, please get in touch with the City of Petaluma Planning Division using the contact information below.

Petaluma City Hall
11 English Street, Petaluma CA 94952
Planning Counter is open to the public 10AM to 3PM, Monday through Thursday. City Hall is closed Fridays.
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