San Diego Votes to Rein in “Towering” ADUs

City council voted to limit the number of units in accessory buildings to six — after confronting backyard developments of up to 100 units behind a single family home.

1 minute read

June 18, 2025, 8:00 AM PDT

By Diana Ionescu @aworkoffiction


SMall backyard cottage ADU in San Diego, California.

A small accessory dwelling unit in San Diego, California. | City of San Diego / San Diego Companion Unit Handbook

The San Diego City Council approved a set of changes to the city’s accessory dwelling unit (ADU) regulations after strong pushback from residents. 

As Omari Fleming explains for NBC San Diego, residents opposed the city’s ADU bonus policies, which allowed developers to, in some cases, build projects of 100 units or more under a policy designed to promote ‘gentle density’ and backyard cottages. Although most applications are for additions of 4 to 7 units, by the end of 2023, at least one application had 148 proposed units.

The council ultimately voted to restrict ADUs to a maximum of six units and two stories, depending on lot size. “Another big change that some homeowners are happy about is no ADUs in cul-de-sacs in high-fire areas. They'll also be required to have parking if they're not near public transportation.”

The changes will require a second approval by the council as well as the mayor to pass.

Monday, June 16, 2025 in NBC San Diego

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SMall backyard cottage ADU in San Diego, California.

San Diego Votes to Rein in “Towering” ADUs

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