San Diegans at Odds Over ‘Granny Towers’

A provision in the city’s ADU ordinance allows developers to build an essentially unlimited number of units on single-family lots.

2 minute read

November 29, 2023, 10:00 AM PST

By Diana Ionescu @aworkoffiction


SMall backyard cottage ADU in San Diego, California.

An example ADU provided in San Diego's COmpanion Unit Handbook. | City of San Diego / San Diego Companion Unit Handbook

Developers in San Diego are using the city’s ADU Bonus Program to build multi-unit accessory dwelling units (ADUs) that go far beyond the typical ‘granny flat,’ reports Ben Christopher in CALmatters. “The city’s one-of-a-kind ordinance offers landlords a one-for-one deal. If they agree to construct an ADU and keep the rent low enough for San Diegans making under a certain income, they’re automatically permitted to build a second ‘bonus’ unit, which they can rent at whatever price they like.”

The law generally allows for up to five units on one property. “But in bus-and train-adjacent ‘transit priority’ areas — a designation that covers much of San Diego’s urban core — a landlord can alternate affordable and bonus units again and again and again.” Although there are height and floor area ratio limits, “you can squeeze in an awful lot of ADUs within those parameters.” In one case, a single lot now holds nine apartment units, of which four are ADUs. According to the city, a typical ADU application includes 4 to 7 units, while the largest project with a submitted application is 148 units. 

As Christopher explains, “Depending on your perspective, San Diego’s ‘crafty little maneuver’ is either an ingeniously clever use of state law to provide a much needed boost to the local housing supply or a sneak effort to foist an intolerable degree of construction and density upon unsuspecting residents while only providing a token degree of affordability.”

Tuesday, November 28, 2023 in CALmatters

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