SB 9 Explained

Senate Bill 9 is a California state law that enables homeowners to split their single-family residential lot into two separate lots and build up to two new housing units on each.

2024 Guide to Senate Bill 9: Revolutionizing California’s Housing Landscape

The Legal Framework
Senate Bill 9, also known as the California Housing Opportunity and More Efficiency (HOME) Act, came into effect on January 1, 2022. This landmark legislation, signed on September 16, 2021, is a pivotal component of California’s strategy to alleviate its severe housing crisis. Dubbed the “duplex bill,” SB 9 enables homeowners to either subdivide their urban single-family residential lots or construct additional residential units, thereby maximizing property utility and addressing housing shortages.

Streamlined Approval Process
Traditionally, the approval process for constructing two-unit developments or subdividing property was discretionary, leading to inconsistencies. SB 9 transforms this process into a ministerial one—objective and uniformly applied—significantly simplifying and speeding up project approvals for homeowners. This initiative is designed to lower barriers to residential development, making it more feasible for property owners to contribute to solving the housing shortage.

Local Compliance and Regulations
While SB 9 mandates statewide compliance, it permits local governments to implement their own objective design standards and limitations, provided these do not contravene state law. Nonetheless, some localities have faced criticism and legal action from the State Attorney General for enacting ordinances that defy the spirit and letter of SB 9.

Addressing the Housing Shortage
California faces an urgent need for affordable housing, particularly in metropolitan areas like Los Angeles, where the deficit contributes to escalating rents and displacement. The state requires an estimated 3.5 million new housing units by 2025 to satisfy demand, a target far from the current construction rate of fewer than 80,000 homes annually. The widespread legalization of accessory dwelling units (ADUs) in 2017 has boosted housing production, yet falls short of closing the gap.

The Impact of Zoning Laws
A significant barrier to housing development is the prevalence of single-family zoning, which restricts properties to one house per lot. This zoning practice covers nearly three-quarters of California’s developable land, severely limiting housing diversity and urban expansion. The attachment to single-family homes, emblematic of the “California Dream,” is increasingly out of reach for many, necessitating a shift in zoning regulations to accommodate modern living arrangements like multigenerational households and communal living.

Development Opportunities Under SB 9
SB 9 allows qualifying single-family properties to add a second unit or split the property into two lots, each potentially housing a duplex or ADUs, subject to local guidelines. Homeowners must reside in one of the new units for a minimum of three years post-subdivision. This regulation offers a pathway for not only accommodating extended family but also for generating rental income.

Eligibility and Exclusions
SB 9 focuses on urban single-family properties but excludes those located in sensitive areas such as historic districts, flood zones, fire hazard zones, and lands designated for agricultural or ecological conservation. Properties with a history of rent-controlled status or tenant evictions within the past 15 years are also ineligible.

Potential Benefits and Community Impact
By enabling lot splits and additional units, SB 9 enhances property owners’ ability to unlock equity, create new homeownership opportunities, and facilitate multigenerational living—aligning with both financial and societal benefits. Each additional rental unit helps mitigate the housing shortage, providing long-term benefits for the broader community.

Navigating Challenges
Homeowners may face challenges related to permitting and financing, especially given the novelty of SB 9. Each municipality may interpret and apply the rules differently, potentially causing delays. However, as familiarity with SB 9 increases, these challenges are expected to diminish. Financial institutions and city planning departments are gradually adapting to the new law, which will streamline future development projects.

Partnering for Progress
At Homestead, we are committed to empowering homeowners to leverage SB 9 for community betterment and personal financial gain. We provide resources and support for navigating the complexities of property development under this new law, including financing solutions and detailed guidance through our SB 9 City Guides and Homestead SB 9 Library.