Senate Bill 9 Summary

Monday, December  27, 2021

The Department is providing a brief summary of Senate Bill (SB) 9, which will take effect on January 1, 2022. This summary is not intended as a complete statement of the law, which is available in full at the California Legislative Information site

The law requires local agencies to ministerially approve urban lot splits and two-unit residential projects in single-family residential zones when certain criteria are met. Note that within unincorporated areas, SB 9 only applies to “urbanized areas or urban clusters” as designated by the United States Census Bureau. In addition, SB 9’s application within the coastal zone is very limited – all coastal zone land use regulations continue to apply, except that the law specifies that a local agency shall not be required to hold public hearings for coastal development permits for SB 9 projects.

SB 9 projects must comply with objective zoning standards, objective subdivision standards, and objective design review standards that do not conflict with SB 9. Application of objective standards must allow for development of at least two 800 square foot residential units.

The law includes many detailed requirements to qualify for ministerial approval. Some of those requirements are highlighted here:

  • SB 9 urban lot splits and two-unit housing development projects must not result in the demolition or alteration of affordable housing, rent-controlled housing, housing that was withdrawn from the rental market in the last 15 years, or housing occupied by a tenant in the past 3 years.
  • The subject property cannot be designated as a local or state historic landmark or located within a local or state historic district.
  • Units created through SB 9 may not be used for short-term rentals of less than 30 days.
  • Parcels may not contain prime agricultural land, wetlands, protected species habitat, or land subject to a conservation easement. Parcels may be located in a very high fire hazard severity zone, earthquake fault zone, floodplain, floodway, or contain hazardous materials if they meet certain conditions.
  • Urban lot splits must result in two parcels of approximately equal lot area (60/40 split at most), with each new parcel containing at least 1,200 square feet;
  • A parcel proposed for an urban lot split cannot have been established through a prior SB 9 lot split;
  • Adjacent parcels cannot have been previously subdivided through an SB 9 lot split by the lot owner or anyone acting “in concert with” the owner;
  • Lots created by an SB 9 lot split may only be used for residential uses;
  • An SB 9 urban lot split applicant must sign an affidavit stating that they intend to live in one of the units for three years, unless the applicant is a community land trust or qualified nonprofit corporation.

In all cases, a local agency can deny an otherwise qualified urban lot split or two-unit housing development project if the building official determines that the project would have a specific, adverse impact on public health and safety or the physical environment that cannot be mitigated.

See a map of potential eligibility for ministerial approval of two-unit residential projects and urban lot splits in single-family residential zones on our County GIS application »

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