Converting a Garage to an ADU? Cities Can't Require Replacement Parking

You've got an old detached garage doing nothing but collecting boxes, and the plan is obvious: turn it into an ADU. Then the planner hands you a condition — before you can convert it, you have to build a replacement parking space somewhere else on the lot. On a tight urban parcel, that one requirement can sink the whole project.

Here's the thing: for an ADU conversion, that replacement-parking demand isn't something the state lets a city impose. And HCD has been striking the rule out of ordinance after ordinance.

What HCD told Irvine

In a January 7, 2025 findings letter reviewing Irvine's ADU ordinance, HCD flagged the City's parking section. The ordinance read:

"When a garage, carport, or covered parking structure is demolished in conjunction with the construction of an accessory dwelling unit or converted to an accessory dwelling unit, replacement spaces must be provided on-site"

That's the City's language — and HCD's position is that it can't stand. HCD pointed to the controlling statute, Government Code § 66314(d)(11), quoting it in the letter:

"When a garage, carport, covered parking structure, or uncovered parking space is demolished in conjunction with the construction of an accessory dwelling unit or converted to an accessory dwelling unit, the local agency shall not require that those offstreet parking spaces be replaced."

HCD's conclusion was blunt. Requiring the offstreet parking to be replaced when a garage, carport, or covered parking structure is converted into an ADU is, in its words, "in direct violation of State ADU Law." It directed the City to remove the replacement requirement.

Verified against HCD's ADU Ordinance Findings Letter to the City of Irvine (January 7, 2025), Finding 13, quoting Gov. Code § 66314(d)(11).

The parking category cities keep leaving out

Look at the statute's list: garage, carport, covered parking structure — or uncovered parking space. That last category was added by SB 1211, effective January 1, 2025. Plenty of ordinances stop short of that full list — most often by leaving out uncovered spaces — and HCD keeps catching the gap.

• Duarte — its ordinance waived replacement only for covered parking. HCD's March 17, 2026 letter told the City to amend it "to include non-replacement of uncovered parking."
• Ukiah — the ordinance covered garages, carports, and covered structures but left out uncovered spaces; HCD's April 24, 2025 letter flagged the same omission.
• Fort Bragg — HCD's September 5, 2024 letter found the ordinance exempted garage conversions but "does not exempt ADUs converted from covered parking structures, like carports," and told the City to broaden it.
• Coronado — the ordinance said replacement spaces "shall be provided" when an ADU replaces a garage or other required parking; HCD's December 10, 2025 letter found that "State ADU Law limits replacement parking requirements."

Five jurisdictions, one recurring defect. When HCD corrects the same ordinance language town after town, it stops looking like a local quirk and starts looking like a bright line under the statute.

What it means for your conversion

If your ADU is a conversion — a garage, carport, covered structure, or an uncovered space cleared to make room — the baseline under § 66314(d)(11) is that the city cannot force you to replace the lost parking. So when a "replacement parking" condition shows up on your plan check, it's fair to ask the planner to name the authority behind it.

Two caveats, stated plainly. HCD's findings letters are the department's enforcement position, not a court ruling — a city can disagree and defend its ordinance, and only a court settles it for good. And it's the statute doing the real work here, not the letter. So confirm the current rule with your building department or your attorney before you rely on it for your own project. This isn't legal advice.

But the direction is consistent, and it's written into the code: the parking you give up to build an ADU conversion is parking the state says you don't have to rebuild.

What CrossBeam does with it

When the letter lands on your desk, CrossBeam turns it around the same day: what each item is actually asking, the code or law behind it, and a written response you can hand to your team or your attorney — the back-and-forth that used to eat weeks, done in a couple of hours.