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SB 9 & SB 10

Duplex

California Senate Bill (SB) 9 allows for the ministerial (staff-level) approval of certain housing development projects containing up to two dwelling units (i.e., duplexes) on a single-unit zoned parcel. The legislation also allows for the ministerial approval of certain lot splits to allow property owners to construct up to two units on the newly created lots.

SB 9 was passed by the California Legislature and took effect January 1, 2022.

Qualifying Projects

SB 9 allows housing development projects containing no more than two dwelling units on a single-unit zoned parcel to be permitted on a ministerial (staff-level) basis, upon satisfaction of a number of qualifying criteria that include the following:

  • The project site is zoned R-1 (Single-Unit Residential).
  • The project site is not subject to a recorded covenant, ordinance, or law that restricts rents to levels affordable to persons and families of moderate, low, or very low income.
  • The project site is not within a very high fire severity zone, a hazardous waste or hazardous list site, within a delineated earthquake fault zone, or within certain 100-year flood zones.
  • The project would not require demolition or alteration of any housing that has been occupied by a rental tenant at any time in the last three years.
  • The project site is not within a historic district or property included on the State Historic Resources Inventory, as defined in Section 5020.1 of the Public Resources Code, or within a site that is designated or listed as a city or county landmark or historic property or district pursuant to a city or county ordinance.

Development Standards

Objective zoning, subdivision, and design review standards may be imposed provided:

  • Such objective standards do not preclude the construction of either of the two units being less than 800 square feet in floor area.
  • No setbacks are required for an existing structure or a structure constructed in the same location and to the same dimensions as an existing structure. In other circumstances, four-foot side and rear yard setbacks may be required.
  • Parking of no more than one space per dwelling unit is specified, except no parking is required for projects a) within a half-mile walking distance of a high-quality transit corridor or a major transit stop or b) within one block of car share. El Camino Real is considered a high-quality transit corridor, and the Burlingame Caltrain and Millbrae BART/Caltrain stations are considered major transit stops.
  • The rental of any unit created must be for a term longer than 30 days (no short-term rentals allowed).
  • Individual units may be either attached (duplex) or detached (cottages), provided the structures meet building code safety standards and are sufficient to allow separate conveyance.

Projects that conform to the objective zoning, subdivision, and design review standards shall be approved ministerially, and are not subject to the California Environmental Quality Act (CEQA).

Lot Splits

In addition to permitting two units on a single family lot, the legislation allows qualifying lot splits to be approved ministerially pursuant to a parcel map, upon meeting a number of criteria, including many of the same criteria for the two units described above. Additional criteria include the following:

  • Each parcel must be at least 40 percent of the original parcel's size.
  • Each parcel must be at least 1,200 square feet in lot size.
  • There cannot be a sequential lot split on the same parcel, nor can there be a lot split if the owner of the parcel being subdivided (or someone working in concert with that owner) has subdivided an adjacent parcel pursuant to this lot split legislation.
  • No right-of-way dedication or off-site improvement may be required. However easements for public services and facilities, and/or access to the public right-of-way may be required as conditions of approval.
  • The parcel must be limited to residential use.
  • An affidavit that the applicant intends to use one of the housing units as a principal residence for at least three years from the date of approval is required.
  • A condition that requires correction of nonconforming zoning conditions shall not be imposed.
  • Accessory dwelling units (ADUs) or Junior ADUs (JADUs) may be restricted if there is a lot split.

In addition to the increase in density in single-family zones and lot splits in single-family zones, SB 9 increases the extension of a map life from 12 months to 24 months and allows four years of extensions in lieu of three years for subdivision maps with off-site improvements above qualifying costs (Gov't Code Sec. 66452.6).

Information contained in this summary is for general education and knowledge, but is not designed to be, and should not be used as, legal advice.

Application Forms

Information/Submittal Requirements Checklist
Application Form
Qualifying Criteria Checklist

Property Owner Affidavit

Applications must first be submitted to the Planning Division for review and approval.  Once approval is granted by the Planning Division, an application for a building permit may then be submitted to the Building Division.  For questions regarding building permit applications, please contact the Building Division at buildingpermits@burlingame.org.  

Please note that for a project that includes an urban lot split, a separate map application to the Public Works - Engineering Division will be required.  For questions regarding map applications, please contact the Public Works - Engineering Division at dpw@burlingame.org


Adoption of SB 9 Regulations 

Currently the City of Burlingame proposes to adopt SB 9-compliant regulations in two phases:

Phase 1 (adopted December 2021) incorporated basic objective development standards into the ongoing Zoning Ordinance Update. Standards are based on existing R-1 standards for building size, lot coverage, setbacks, and building height (unless conflicting with standards summarized above).  The standards have been adopted as Chapter 25.20.080 (Two-Unit Residential Overlay) of the Municipal Code and are in effect. Click here to view the standards. 

Phase 2 will refine the basic standards to further reflect the building patterns particular to Burlingame's neighborhoods. This phase will focus on detailed objective design standards, and will involve community engagement.  

Phase 1 Ordinance - Adopted December 6, 2021
A comprehensive update of the Zoning Code was introduced at the November 15, 2021 City Council meeting, and adopted at the December 6, 2021 meeting. Regulations intended to comply with SB 9 are established as a zoning overlay, found in Section 25.20.080 (Two-Unit Residential Overlay). The regulations become effective January 5, 2022.
Zoning Code

City Council Presentation and Discussion - October 18, 2021
The City Council received a presentation and held a discussion of SB 9 and SB 10 at its meeting on October 18, 2021.
Staff Report
Presentation Slides

Planning Commission Review of Draft Standards - October 25, 2021
The Planning Commission reviewed draft "Phase 1" standards at its meeting on October 25, 2021. The standards are included as an overlay in Section 25.20.080 of Article 2 in the Draft Zoning Ordinance Update (pages 60-62 of the pdf):
Draft Zoning Ordinance Article 2


Senate Bill (SB) 10 

California Senate Bill (SB) 10 allows (but does not require) local agencies to adopt an ordinance to allow up to 10 dwelling units on any parcel if the parcel is within a transit-rich area or urban infill site.

While the City encourages housing production to meet the needs of its residents and workforce, there are currently no plans underway to adopt such an ordinance. Multiunit residential developers and builders are advised to focus on the City's many multiunit residential and mixed use zoning districts, some of which have no density limits as an incentive to accommodate new housing.