Homeowners in Southern California are starting to take advantage of a state law that allows lot splitting and higher density in residential areas in an effort to increase housing supply and affordability.

Three years after a law allowing lot splitting was passed in California, San Diego is starting to see its effects as homeowners sell off or build on previously unused parts of their properties.
According to a KPBS article by Andrew Bowen, “SB 9, or the California HOME Act, allows homeowners to split their lots in two and build up to two homes on each parcel — even if local zoning restricts the property to a single detached house.”
The bill’s passage in 2021 was considered a victory for housing advocates who want to lower barriers to building more housing, but cities and homeowner groups continue to fight the law in courts and through more creative means.
“It does take a while for the general public to know about the law, and for planning departments to adjust to state laws,” says Muhammad Alameldin, a policy associate at UC Berkeley's Terner Center for Housing Innovation. For the law to make an impact on the housing supply, builders who specialize in small-scale infill can help homeowners understand the process and access resources to lower the costs of construction, Bowen writes. Cities including Sacramento and Los Angeles are also working to eliminate barriers and reduce costs for homeowners in other ways, such as issuing pre-approved plans for accessory dwelling units (ADUs).
FULL STORY: Three years into California duplex law, San Diego homeowners start to cash in

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