The same ordinance that made it easier to convert a Hermosa Beach garage into a legal rental unit also made it a little harder to park in front of your own house. Nobody wrote that trade-off into the press release, but if you read the ordinance and the city's parking policy side by side, the connection is hard to miss.
Hermosa Beach adopted a new accessory dwelling unit ordinance this spring, and separately, the city overhauled its residential parking permit program at the start of the year. Neither policy references the other. But if you own a Hermosa Beach property with a garage, or you're buying one that already has a converted bonus room out back, the two rules meet in the same driveway, and the outcome is worth understanding before you sign anything.
What Changed on April 23
Hermosa Beach's ADU rules now live in their own chapter of the municipal code, Chapter 17.21, adopted through Ordinance 26-1498 and effective April 23, 2026. It splits accessory units into two classes. Class 1 covers anything under 800 square feet and skips the architectural matching requirement entirely, so a small studio doesn't need to mimic the roofline of the main house. Class 2 units have to match the primary dwelling's materials and roof slope.
The detail that surprises most sellers involves height. A standalone, two-story detached ADU isn't buildable in Hermosa Beach at all. The only way to get a second story on an accessory unit is to attach it to an existing two-story primary residence, and even then it's capped at 25 feet or the underlying zone's height limit, whichever is lower. That's a meaningfully tighter rule than Manhattan Beach, which allows a 26-foot allowance above a detached garage. If you're comparing a Hermosa Beach listing to something a few miles north and both mention an "ADU-ready garage," the ceiling on what you can actually build is not the same.
The ordinance also carries forward a state-law protection that matters more than it sounds: when an existing garage is demolished or converted into an ADU, the city cannot require you to replace that parking space. On paper, that's a win for anyone sitting on an underused garage. In practice, it's only half the story.
The Permit Cap Nobody Mentions at the Open House
Hermosa Beach runs one of the tightest residential parking permit systems in the South Bay, and it applies per address, not per unit. Under the program the City Council updated on January 13, 2026, effective February 2, households are capped at three residential permits a year, with a fourth available only when the number of drivers at that address exceeds the on-site parking actually available. Getting that fourth permit requires signing an affidavit under penalty of perjury, and the city has said it will suspend permit privileges for two years if the paperwork turns out to be false.
Mayor Rob Saemann put the intent behind the update plainly:
"Our goal is to meet Hermosa residents' parking needs while ensuring our City's limited parking spaces are used fairly and effectively."
Here's where the two policies collide. Converting a garage into an ADU removes an on-site parking space, which can genuinely help the original household qualify for that fourth permit. But the permit cap belongs to the address, not to the number of legal dwelling units on it. Add a second household through a legalized ADU, and you haven't added new permits to draw from. You've added a second driver competing for the same three, or at most four, permits the property already had.
| Scenario | On-site parking after conversion | Permits available to the address |
|---|---|---|
| Garage intact, single household | 1 space | 3 permits, no affidavit needed |
| Garage converted to ADU, no other on-site parking | 0 spaces | Up to 4 permits, but affidavit required and now split across two households |
For a seller, that's a fact worth putting in writing before a buyer discovers it during their own due diligence. For a buyer weighing a Hermosa Beach property with an ADU already built out, it's a question worth asking directly: how many permits does this address currently hold, and how many drivers are already splitting them?
If the Conversion Predates 2020
Plenty of Hermosa Beach garage conversions were never permitted in the first place, often built by a previous owner decades ago. State law now gives those units a path forward. Assembly Bill 2533, in effect since January 1, 2025, prevents a city from denying a legalization permit for an ADU or junior ADU built before January 1, 2020, unless the unit is genuinely substandard under the state's health and safety code. Hermosa Beach folded this into its own ordinance at Section 17.21.090.
What that means for a real transaction:
- Legalization review is ministerial in Hermosa Beach. The Community Development Department handles it directly at 1315 Valley Drive, with no hearing, no design review board, and no council vote required.
- The city has 15 business days to determine whether an application is complete, and 60 days after that to approve or deny it. If it doesn't respond, the permit is deemed approved automatically.
- None of this removes the disclosure obligation. California Civil Code requires sellers to disclose known unpermitted alterations on the Transfer Disclosure Statement, and that requirement doesn't go away in an as-is sale.
For a seller sitting on a decades-old garage conversion, the practical choice is rarely "disclose or don't." It's whether to run the legalization process before listing, so the buyer inherits a permitted unit instead of an open question, or to disclose it clearly and let the buyer factor the legalization timeline into their offer.
What the Building Department Won't Let You Ignore Underground
Anyone eyeing a below-grade conversion, a basement, a sunken family room, anything dug lower than the existing slab, runs into a constraint that has nothing to do with the ADU ordinance and everything to do with geology. Hermosa Beach requires a geotechnical report before construction begins, because groundwater in parts of the city sits as shallow as six to fifteen feet below the surface, with subterranean streams running from inland sources out to the ocean. Digging a basement in the coastal zone can breach that water table and cause flooding that has nothing to do with weather.
It's a detail that rarely shows up in a listing description, but it shapes what's actually feasible on a given lot. A garage-level conversion and a true basement conversion are not interchangeable projects in this city, and the geotechnical requirement is the reason why.
What This Means Before You List, or Before You Write an Offer
A few things worth confirming before a Hermosa Beach garage conversion becomes part of a transaction:
- Whether the conversion was permitted, and if not, whether it predates January 1, 2020 and qualifies for the AB 2533 pathway.
- How many residential parking permits the address currently holds, and whether a fourth-permit affidavit is already on file.
- Whether any structural work involved digging below existing grade, which would trigger the geotechnical requirement regardless of ADU status.
- Whether the unit falls under Class 1 or Class 2 standards, since that affects what future buyers can or can't modify without a design review.
None of this is a reason to walk away from a property with a converted garage. It's a reason to get the permit history and the parking situation in writing early, rather than discovering the gaps during escrow.
Frequently Asked Questions
Does converting a garage into an ADU automatically qualify a Hermosa Beach household for a fourth parking permit? Not automatically. The city requires an affidavit showing the number of drivers at the address exceeds the on-site parking available, and false statements carry a two-year suspension of permit privileges.
Can a legalized ADU get its own separate set of parking permits? No. The permit cap is tied to the residential address, not to the number of legal units on the lot. An ADU adds a household to the property, not additional permits.
Is a two-story detached ADU an option in Hermosa Beach? Not as a standalone structure. A second story on an accessory unit is only possible when it's attached to an existing two-story primary residence, capped at 25 feet or the zone's height limit, whichever is lower.
If you're weighing a sale that involves a garage conversion, or an offer on a property that already has one, the paperwork underneath it matters as much as the finish work inside it. Amy Pearce has walked South Bay sellers through exactly this kind of disclosure and permit history before, and can tell you where a specific Hermosa Beach property stands. Start with a free home valuation and we'll go through the permit and parking picture together before you list.
