California SB 9 Lot Splits & Housing | Ojanen Chiou Architects

California SB 9: Expanding Your Property's Potential //

California SB 9 creates new opportunities for qualifying homeowners to add housing, subdivide residential property, and explore new ways to use their land. Understanding the options—and how they apply to a specific property—is the first step in determining its development potential.

Senate Bill 9 (SB 9) – the California Housing Opportunity and More Efficiency (HOME) Act, is a California state law that took effect in 2022. The law provides qualifying property owners with new options for adding housing to lots in single-family residential zones through a streamlined, ministerial approval process.

SB 9 provides two primary development options. The TWO-UNIT provision allows up to two primary dwelling units on a qualifying single-family lot, while the LOT SPLIT provision allows an eligible property to be subdivided into two lots. When both provisions are used, SB 9 can potentially allow up to four primary dwelling units within the area previously occupied by a single lot.

Depending on the development approach, SB 9 can create opportunities for additional housing, multigenerational living, rental housing, or the creation of a second residential lot. Lot splits and development are subject to eligibility requirements and local objective standards.

The concept is relatively simple, but determining whether a property qualifies, evaluating the available development options, and navigating local requirements can be more complex.

Benefits of SB 9

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- Creates opportunities to increase property value.
- Provides additional housing for extended or multigenerational family.
- Creates opportunities for long-term rental income.
- Can support long-term family wealth and property ownership.
- Expands housing options within established residential neighborhoods.
- Allows communities to add housing gradually while making more efficient use of existing land and infrastructure.
- Creates opportunities for smaller homes, rental housing, and entry-level homeownership in areas where housing options may otherwise be limited.
- Promotes infill development and more efficient use of existing infrastructure and resources.
- Creates opportunities for additional housing within established neighborhoods, potentially reducing development pressure on undeveloped land and open space.
- Creates opportunities for residential construction and related professional services, supporting local jobs and businesses.
- Can expand the local housing supply and property tax base while making more efficient use of existing infrastructure.
- The property must be located in a qualifying single-family residential zone within an urbanized area.
- For an SB 9 lot split, the two resulting lots must be approximately equal in size, with neither smaller than 40% of the original lot area. Each resulting lot must generally be at least 1,200 square feet.
- A property cannot be repeatedly subdivided using the SB 9 lot-split provisions, and additional restrictions apply to adjacent lots under common ownership.
- SB 9 includes protections for existing rental and affordable housing and limits projects involving the demolition or alteration of certain tenant-occupied housing.
- Certain properties are excluded based on environmental, historic, agricultural, fire-hazard, flood, conservation, and other site conditions.
- An owner-occupancy requirement applies to applicants using the SB 9 urban lot-split provisions, subject to exceptions established by state law.
- Local jurisdictions may apply qualifying objective zoning, subdivision, design, access, utility, and other development standards.
- Projects remain subject to applicable subdivision procedures, building requirements, utility requirements, and development fees.
- Eligibility and development potential depend on the specific property and local requirements.