ADU Parking Rules in San Diego: What Changed

When we wrote earlier this month about the new California ADU laws that took effect January 1, we promised a closer look at the change that's flying under the radar but matters most for real projects: parking.

For years, parking was the quiet killer of ADU plans in San Diego. A homeowner would call us excited about a granny flat, we'd look at the lot, and the math would fall apart — not because of the unit itself, but because of where the cars were supposed to go. The new state rules take that obstacle off the table for a huge share of the county. Here's what actually changed.

The half-mile transit rule

Under the new law, if your property sits within half a mile of public transit, the city can't require any parking for your ADU at all. Not one space.

Think about what half a mile from transit means in this city. It covers broad swaths of North Park, Normal Heights, City Heights, Hillcrest, and University Heights. It runs along the trolley lines through Mission Valley and down to the border. It follows the Coaster through coastal North County. Many of the neighborhoods where ADUs make the most sense — older lots, established streets, real demand for rental housing — are exactly the neighborhoods this rule unlocks.

If your lot falls outside those zones, the requirement is modest anyway: generally one space, and it can be tandem in your existing driveway. No new curb cut, no paving over the garden.

The garage conversion breakthrough

The second change might be even bigger. Previously, if you converted your garage into an ADU, many jurisdictions required you to replace the parking spaces you eliminated — which often meant building a new carport or paving more of the lot, and frequently killed the project. Under the new rules, when a garage is demolished or converted to build an ADU, replacement parking can no longer be required.

For San Diego's housing stock, this is enormous. Our midcentury ranches in Clairemont, Serra Mesa, and Allied Gardens almost all come with attached two-car garages that, let's be honest, mostly store boxes and a kayak. Each one is now a candidate for conversion — existing foundation, existing roof, existing walls — without the hidden cost of rebuilding parking somewhere else on the lot.

What this means for your project math

Parking flexibility changes ADU feasibility in three practical ways:

• Smaller lots qualify. Lots we would have ruled out two years ago now pencil, because the buildable area isn't competing with a parking pad.
• Garage conversions got simpler and cheaper. The structure is already there; the law no longer makes you pay a parking penalty to use it.
• Backyards stay backyards. You can keep the patio and the citrus tree instead of paving for a car that was always going to park on the street anyway.

None of this waives the rest of the process — setbacks, utilities, fire access, and design standards still apply, and the city's implementation details are still settling as departments catch up with Sacramento. That's normal in the first months of a new law, and it's why the sequencing of design, permits, and construction matters. It's the same discipline we bring to every project we run.

Worth a fresh look

If you priced an ADU in 2017 or 2018 and walked away, the ground has genuinely shifted — between the parking rules, reduced fees, and the new junior ADU option, a "no" from two years ago may be a "yes" today. We're happy to take a look at your lot and tell you straight what's possible now under the current ADU rules.

Request a consultation or give us a call — tell us about your lot, and we'll tell you what January made possible.