CALIFORNIA HOA RESTRICTIONS ON ADU CONSTRUCTION
OVERVIEW
Although most of the statutory protections have been in place for years, 2025 continues to reveal how boards resist compliance in subtle but persistent ways.
Accessory Dwelling Units (“ADUs”), sometimes referred to as “granny flats,” “accessory apartments,” or “in-law units,” are now a permanent fixture in California housing policy. But for many homeowners living in HOA-governed communities, the legal path to building one still feels uncertain despite the powerful public policy supporting California’s ADU laws. To be sure, state law clearly limits what HOAs can do to block or delay ADU construction, but that hasn’t stopped many boards from trying.
This article cuts through the confusion. It explains exactly what your HOA can and cannot do under current California law when it comes to ADUs. Whether you’re being told your ADU “doesn’t comply,” facing unexplained delays, or dealing with newly invented architectural standards, this article will help you separate fact from fiction. You’ll learn which HOA restrictions are legally valid, which are not, and what steps you can take when your association oversteps. If your board is misrepresenting the law—or ignoring it entirely—this guide will show you how to fight back.
If you’d like to read other articles of mine on this particular subject, then you can click on: “Can My California HOA Legally Block an ADU?” and “What to Do If Your HOA Delays or Ignores Your ADU Application.”
If you’d rather take a look at a quick reference guide ADU laws in California HOAs, then you can click on my Fact Sheet: “Can California HOAs Block ADUs? What the Law Says About HOA Restrictions on ADU Construction.”
CAN A CALIFORNIA HOA LEGALLY DENY AN ADU?
Under current California law, the answer is almost always no, and the state’s newest statutory updates make that clearer than ever.
In most cases, a California HOA cannot legally prohibit a homeowner from building an ADU on their property. The state’s ADU laws, reorganized and expanded in 2025, make it illegal for homeowners’ associations to adopt or enforce rules that unreasonably restrict the construction or use of an ADU or Junior ADU.
This means that even if your HOA’s CC&Rs include language that appears to prohibit detached structures—e.g., “granny flats,” “accessory apartments,” or any other common euphemisms for an ADU—those provisions are illegal and unenforceable if they conflict with state law. And if your HOA is refusing to approve your plans outright, or demanding that you “apply for a variance” just to consider your request,—that’s a major red flag.
As I discuss below, it’s true that HOAs retain limited authority to impose reasonable design restrictions (like architectural uniformity or utility safety compliance), but they cannot flatly deny ADUs, nor take steps to make ADU construction impracticable, just because the board or architectural committee doesn’t want them in the community.
WHAT STATE LAW SAYS ABOUT ADUs IN CALIFORNIA HOAS
California’s ADU laws are not vague. The state legislature has made it explicitly clear that homeowners in single-family residential zones have the right to build ADUs and Junior ADUs (“JADUs”) on their property, regardless of whether the home is located inside a common interest development. That means HOAs can’t override or ignore the law by citing outdated CC&Rs, manufactured approval processes, or aesthetic objections. If your ADU complies with state and local law, your HOA can’t legally stop you from building it.
The controlling statute is Civil Code section 4751, which prohibits HOAs from imposing or enforcing any requirement that “unreasonably restricts” the construction or use of an ADU or Junior ADU. This section makes clear that HOAs cannot delay, obstruct, or deny otherwise lawful ADU construction by citing their own internal rules. In short, under that law, HOAs are expressly prohibited from adopting or enforcing any restriction that “unreasonably” limits the construction or use of ADUs and JADUs. Many experts, including myself, also argue that Government Code section 66317 (previously codified at Gov’t Code, § 65852.2), applies to HOAs who, in the context of common interest developments, act as quasi-governmental entities. Regardless, it’s clear that HOAs are expressly prohibited from adopting or enforcing any restriction that “unreasonably” limits the construction or use of ADUs and JADUs.
While HOAs can adopt “reasonable” standards related to design and placement, they may not ban ADUs entirely, nor may they impose arbitrary rules designed to obstruct the process. For example, an HOA might be permitted to require that your ADU’s exterior materials match your primary residence or that utility hookups meet safety standards. But it cannot:
- Ban all ADUs outright.
- Impose additional parking requirements beyond what the city requires.
- Refuse to review your application based on “neighborhood character” or aesthetics.
- Demand setbacks or height restrictions beyond those in local zoning law.
- Delay approvals indefinitely or refuse to timely process ADU plans.
In short, HOAs are not exempt from state law, and if they ignore the law altogether, or try to sidestep the law by manipulating their internal rules or approval processes, they expose themselves to significant legal liability.
WHAT CALIFORNIA HOAS CAN STILL REGULATE WHEN IT COMES TO ADUS
Even though California law limits your HOA’s power in regards to your right to construct an ADU on your property, it doesn’t prevent your HOA from imposing some regulations over its construction. While associations cannot impose blanket ADU bans or delay approvals indefinitely, they do retain authority over certain design, placement, and community-related aspects of ADU construction. These are often referred to as “reasonable restrictions,” and courts will generally uphold them as long as they don’t directly conflict with state law or make ADU construction impractical or unreasonably more expensive.
For example, your HOA may still have a say regarding the following issues:
- Architectural consistency. HOAs can require that your ADU uses exterior materials, colors, and design features that are consistent with your primary residence or the aesthetic standards in your governing documents. They can’t reject your project arbitrarily, but they can insist on visual uniformity if applied fairly.
- Setbacks and placement. Associations may enforce setback rules or placement restrictions that are already consistent with local zoning codes. They cannot, however, impose additional limitations that go beyond those required by state or local law.
- Noise and nuisance policies. If your ADU will be rented, the HOA may apply its usual noise rules, occupancy limits, or nuisance restrictions so long as those policies are applied uniformly across the community.
- Parking and traffic. While an HOA can’t require additional parking beyond what the city requires, it can enforce community-wide parking policies (like guest space rules or street parking limits) that also apply to the primary residence.
- Approval procedures. Most HOAs will still require that you submit architectural or modification requests through the standard review process. They cannot, however, delay or obstruct your application for the sake of delay, to make it more expensive for you, or to otherwise dissuade you from proceeding with your construction plans.
In short, your HOA can still regulate how an ADU is built, but not whether it’s allowed. If your board uses its discretion as a weapon to block what the law clearly permits, those restrictions are unenforceable.
TACTICS CALIFORNIA HOAS USE TO DELAY OR BLOCK ADU CONSTRUCTION
Even though state law restricts what HOAs can do to stop ADU projects, that hasn’t prevented many bad HOAs from using procedural (and pretextual) tactics to frustrate, delay, or entirely torpedo a homeowner’s efforts to build an ADU. These actions are rarely presented as outright denials. Instead, they’re disguised as architectural standards, application requirements, or timeline extensions, none of which are allowed to “unreasonably restrict” construction under Government Code section 66317.
Here are some of the most common tactics HOAs use to accomplish their restrictive efforts:
- Ignoring or indefinitely “reviewing” your application. Boards may claim they haven’t received your plans, or that your submission is incomplete, even when it meets all stated requirements. The delay isn’t always in writing, which makes it harder to challenge.
- Imposing non-standard requirements. Some HOAs invent rules on the fly, like requiring special renderings, traffic impact studies, or neighbor consent letters, that have no basis in the governing documents or applicable law.
- Misquoting the governing documents. Boards sometimes cite outdated or inapplicable clauses to claim your ADU is prohibited, even though those rules have been overridden by state law. They rely on homeowners not knowing how preemption works.
- Creating additional fees or assessments. A common tactic is to impose “ADU review fees” or other charges that are not listed in the HOA’s fee schedule and are clearly designed to discourage construction.
- Selective enforcement. Boards may claim your ADU isn’t compliant while allowing other homeowners to make similar structural changes. Or they may enforce the same rule inconsistently to favor longtime board allies or former directors.
While none of these tactics may sound like an outright ban, the end result is often the same: your ADU project gets stalled, discouraged, or abandoned. And that’s exactly why these practices, while subtler than a formal denial, are often completely indefensible.
WHAT TO DO IF YOUR HOA IS BLOCKING YOUR ADU PROJECT
If your HOA is trying to block your ADU project, whether by outright denial, endless delays, excessive fees, or misrepresenting its authority, you don’t need to simply accept it. In fact, you should reject such efforts directly and loudly. California law gives homeowners the right to push back, and when used strategically, those rights can stop a bad HOA in its tracks.
Here’s what to do if you find your HOA standing in the way of your ADU:
- Frame the issues in writing and request written justification for the denial or delay. First, prepare a chronological narrative detailing your request (i.e., to construct an ADU on your property), the efforts you made to comply with state law or you’re your governing documents, and the tactics utilized by your HOA to date. Then demand a written explanation of why they’ve acted as they have, including a demand that they explicitly cite a specific rule or statute supporting their position. Most HOAs won’t be able to point to anything enforceable, and getting it in writing gives you a paper trail if litigation becomes necessary.
- Cite state law back to the board. Either in the above-referenced writing, or in a subsequent correspondence, if the board is stalling, misrepresenting its authority, or inventing approval requirements, cite both Civil Code section 4751 and Government Code section 66317. Make it clear that their actions may be unenforceable and could expose the association to legal liability. Show your board that you’re aware of your rights and the basis of your rights. It’s a lot easier to victimize an ignorant homeowner than one armed with knowledge of the law.
- Submit a written demand for IDR. If you think it’s worth your time (because it is not required unless you wish to proceed), demand Internal Dispute Resolution. The Davis-Stirling Act requires the board to agree to any written demand for IDR from a homeowner, and it will give you an opportunity to meet with one or more board members to address the dispute.
- Gather comparison data. If the board has approved similar modifications for other homeowners (e.g., exterior structures, garages, casitas, or add-ons), document those examples. Get photos and video to support your position. That evidence could be significant in proving a claim of selective enforcement.
- Consult with legal counsel. If none of the foregoing works, then it’s time to bring in the big guns. Consult with attorneys who are experts in the Davis-Stirling Act. You should not try to litigate this alone. At MBK CHAPMAN, we represent homeowners in precisely these situations.
The earlier you act, the stronger your position. Boards that know you’re represented—and understand that you know the law—are far more likely to back down before litigation becomes necessary.
CONCLUDING THOUGHT
California law is clear: HOAs cannot impose rules that unreasonably restrict homeowners from building ADUs. But clarity in the statute doesn’t always translate to compliance in the real world. Many boards still resist, delay, or deny ADU applications using outdated CC&Rs, invented requirements, or selective enforcement—and they often get away with it because homeowners don’t know what’s enforceable and what isn’t.
If you’re running into resistance, don’t assume the board is right just because it sounds authoritative. Question it. Demand specifics. And if the delays continue, get legal help. At MBK CHAPMAN, we don’t just understand the law—we enforce it. When your HOA tries to stand between you and your ADU, we’re the ones who make them move.
If you’d like to watch an episode of my podcast where I do a deep dive into California’s ADU laws and how they apply to California HOAs, click: “Can My California HOA Stop Me From Building an ADU?”