San Diego Begins to See Results of State Housing Law

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.

1 minute read

November 1, 2024, 7:00 AM PDT

By Diana Ionescu @aworkoffiction


Small, colorful homes on small lot in San Diego, California.

Small homes in San Diego, California. | RebeccaDunnLevert / Adobe Stock

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).  

Monday, October 28, 2024 in KPBS

Young Professional

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban and Environmental Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban and Environmental Planner

Get top-rated, practical training for planners

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

October 28, 2026 - Zachary Whalen

A car drives through a puddle, making a large splash. Rain pours down.

California plans to bury El Niño’s downpour

If the state plays its cards right, it may be able to store a billion acre-feet of El Niño’s water in aquifers.

October 28, 2026 - Grist

A pencil rendering of Foundry Park, which shows skyscrapers and public green spaces.

Chicago breaks ground on $3 billion megadevelopment

The new neighborhood, titled Foundry Park, will one day host 3,700 residences.

October 23, 2026 - Chicago Sun Times

A swamp in South Carolina with tall pale trees and Spanish moss in the water.

Satanic place names

From streams and lakes to valleys and canyons, I mapped more than 1,000 places named after the Devil.

October 31 - The Daily Yonder

A rendering of a high speed rain station in California, with wide platforms and a sleep train with yellow highlights.

California High-Speed Rail Authority CEO resigns after $600,000 scandal

Under Ian Choudri, the authority used taxpayer dollars to fund first class flights and trips to nightclubs.

October 30 - Cal Matters

 A bridge stretches across the Missouri River at Chamberlain, South Dakota.

Want to study the Missouri River? Soon, you may need unanimous approval from 10 states

Legislation would require 10 governors’ permission to study or build projects moving water outside the basin.

October 30 - South Dakota Searchlight