Don’t Let an Unpermitted Backyard Unit Turn Into a Sale, Refinance, or Code Enforcement Problem — Understanding AB 2533 and San Diego’s Retroactive Permit Process Could Protect Your Property

Jason converted the detached garage behind his San Diego home in 2019. At first, it was meant to solve a family problem, not create one. His mother needed a place to stay nearby, and the garage already had enough room for a small bathroom, a kitchenette, and a sleeping area. The work got done quickly. Everyone moved on.

Then life changed.

A few years later, Jason wanted to refinance. The lender asked a question he wasn’t ready for: “Do you have permits for the secondary dwelling unit?”

He didn’t.

What had once felt like a practical home improvement suddenly became a property issue with real consequences. A sale could get delayed. A refinance could stall. Insurance questions could follow. A tenant situation could become risky. And if a complaint ever reached the city, the problem could become urgent overnight.

Like many homeowners, Jason assumed that because the work was already done, he had only two options: keep hiding it or tear it all out.

That is not always true.

For qualifying properties in the City of San Diego, AB 2533 created a more realistic path to legalize certain unpermitted ADUs and JADUs. That does not mean every unpermitted unit automatically becomes legal. It does mean some homeowners now have a clearer path forward than they did before.

What Is AB 2533?

AB 2533 is the California law that changed the conversation around unpermitted ADUs. For many homeowners, the biggest takeaway is simple: if an ADU was constructed before January 1, 2020, the city generally cannot deny a permit application just because the unit violated building standards or ADU rules when it was created.

That is the part most people hear.

The part they miss is just as important: the law still centers on health and safety. If the unit is substandard, dangerous, or cannot satisfy the conditions required to avoid being treated as a substandard building, the path becomes much harder.

For homeowners in the City of San Diego, the issue is no longer only, “Was this built without permits?” The real question is, “Can this unit be documented, corrected where necessary, and brought to an approvable condition?”

That is a very different question — and for many properties, it is the difference between panic and a plan.

The Truth Many Homeowners Miss: AB 2533 Is Not Automatic Amnesty

A lot of homeowners hear the term “ADU amnesty” and assume the state now gives every garage conversion or backyard unit a free pass.

That is not what is happening.

What the law can do

For a qualifying older unit, AB 2533 can give you a real legalization path instead of shutting the door immediately because the space was created without permits.

In practical terms, that means:

• A qualifying ADU built before January 1, 2020 may still be eligible for retroactive permitting.
• The city’s focus shifts toward habitability, safety, and what must be corrected.
• A homeowner can get a confidential third-party inspection before filing, which can help avoid submitting blind.
• If corrections are needed to address health and safety issues, the process is supposed to move toward fixing the problem rather than punishing the owner just for coming forward.

What the law cannot do

AB 2533 does not magically erase every issue tied to an unpermitted unit.

It does not:

• Automatically legalize a unit the moment you discover the law.
• Protect unsafe or truly substandard construction.
• Guarantee that additions, alterations, or remodeling done later can ignore current code.
• Remove the need for plans, permit review, inspections, and correction work.
• Solve every issue for properties subject to Coastal Act requirements.

That last point matters more than many owners realize. A homeowner may have a qualifying unit and still face a more complicated process because of the property’s location or existing site constraints.

What Makes an ADU “Substandard”?

This is where many legalization efforts succeed or fail.

A homeowner may say, “The space looks fine,” but appearance is not the test. The city looks at whether the unit meets minimum habitability and life-safety expectations and whether the structure falls into substandard conditions that must be corrected.

Common red flags include problems like:

• missing or improper bathroom or kitchen fixtures
• no hot and cold running water
• inadequate heating
• poor ventilation or insufficient natural light
• unsafe or nonfunctional electrical, plumbing, or mechanical systems
• deteriorated foundations, floors, walls, or roof framing
• weatherproofing failures, leaks, broken exterior protection, or major moisture issues
• inadequate exits or missing fire-safety features
• spaces being used for living, cooking, or sleeping when they were never properly suited for that occupancy

This is why a lot of unpermitted garage conversions become complicated. A room can feel comfortable enough for short-term family use and still fall short of what is required for a legal dwelling unit.

The good news is that many units do not need to be demolished. They need to be evaluated honestly, documented accurately, and upgraded strategically.

How the San Diego Legalization Process Usually Works

For homes in the City of San Diego, the legalization path is not just one form and one inspection. It is a sequence.

Step 1: Confirm that the unit actually qualifies

The first question is whether the ADU fits the AB 2533 pathway at all.

That means figuring out:

• when the unit was built
• whether it is really functioning as an ADU or JADU
• whether the property is in the City of San Diego
• whether Coastal Act issues or other location-based restrictions could change the process
• whether the unit appears capable of avoiding substandard status after corrections

This first step matters because homeowners often spend money on plans before they answer the eligibility question correctly.

Step 2: Get a confidential inspection and feasibility review

One of the smartest moves is to evaluate the unit before you submit anything.

A confidential third-party inspection can help you understand:

• what is already acceptable
• what will likely need correction
• what could become expensive
• whether the space is a strong candidate for legalization or a more serious reconstruction effort

This is where experience matters. A homeowner who applies too early may trigger a process without understanding the true scope. A homeowner who waits too long may lose leverage, time, and money.

Step 3: Prepare accurate as-built plans and a site plan

You cannot legalize what you cannot clearly document.

For a serious application, you usually need a clear picture of what exists now, not what someone remembers building years ago. That often means preparing as-built drawings and a site plan that show the property boundaries, setbacks, lot coverage, location of the unit, nearby access, and other critical site information.

This stage also reveals some of the hidden issues that catch people off guard, including fire access concerns, setback realities, utility complications, and design conflicts between what exists and what the city can reasonably approve.

Step 4: Define the correction scope before filing

Not every issue has the same weight.

Some corrections are relatively straightforward: smoke alarms, carbon monoxide alarms, ventilation openings, or egress improvements.

Others can be far more serious: structural repairs, electrical system corrections, plumbing replacement, heating upgrades, or reworking parts of the building envelope.

A strong legalization strategy separates the scope into three buckets:

• what can stay
• what must be corrected
• what should not be touched until the permit path is clear

That distinction can save a homeowner from wasting money on the wrong work at the wrong time.

Step 5: Submit the building permit application

In the City of San Diego, the retroactive permitting process runs through a building permit application submitted online.

If the property already has a code enforcement issue or citation, that needs to be handled carefully and reflected appropriately in the application scope.

This step is where poor planning usually shows. If the plans are vague, the site information is incomplete, or the correction strategy is unrealistic, delays start stacking up.

Step 6: Complete corrections and pass inspections

Even when the city allows the legalization path, the work is not done until the required corrections are completed and inspections are passed.

That can include life-safety improvements, documentation updates, utility-related corrections, access issues, and other code items that must be addressed before the unit is recognized through the permit process.

This is why legalization is not just paperwork. It is a design, permitting, and construction problem that has to be solved in the right order.

Common Upgrades Homeowners Should Expect

Every property is different, but some items show up again and again in unpermitted ADU cases.

Homeowners should be prepared for upgrades such as:

• smoke alarms and carbon monoxide alarms
• emergency escape or rescue openings
• light and ventilation corrections
• heating installation or replacement
• plumbing and electrical repairs
• sanitation fixture corrections
• weatherproofing repairs
• framing or structural reinforcement
• fire access or site-related modifications

The key point is this: a unit does not have to be perfect on day one to have a path forward, but it usually does need to be correctable.

Real-World Scenarios That Catch Owners Off Guard

Scenario 1: The family garage conversion that becomes a rental

What begins as a room for a parent, adult child, or guest often turns into a long-term housing solution. Years later, the owner decides to rent it out for income.

That is usually the moment the risk changes.

Once a space becomes part of your financial plan, the cost of leaving it unpermitted gets much higher. Rent, liability, insurance, and future resale value all become part of the equation.

Scenario 2: The refinance or sale that uncovers everything

Many owners assume no one will ever ask.

Then the appraiser notices the separate entrance. The buyer asks for permit history. The lender wants documentation. The title process raises questions. Suddenly, an issue that sat quietly for years is now sitting in the middle of a transaction timeline.

At that point, “we’ll deal with it later” is no longer a strategy.

Scenario 3: The coastal property surprise

Some homeowners have a strong AB 2533 case on paper and still run into a second layer of complexity because of where the home is located.

If the property is in an area subject to Coastal Act regulations, the normal city bulletin path is not the whole story. Extra approvals can enter the picture, and the process may not be as simple as homeowners expect.

That is why location matters just as much as construction date.

Understanding the Cost Reality

One of the biggest mistakes homeowners make is asking, “How much does it cost to legalize an unpermitted ADU?” as if there is one number.

There isn’t.

The real question is: how close is the unit already to a safe, documentable, approvable condition?

Your total cost may involve:

• feasibility review and inspection
• as-built drawings and site documentation
• permit fees and review costs
• correction work for code and life-safety items
• electrical, plumbing, HVAC, or structural upgrades
• possible utility-related work
• final inspections and project close-out

A clean, well-built garage conversion with minor life-safety issues is a very different job from a badly altered structure with major electrical problems, no heat, poor drainage, and no proper exit strategy.

AB 2533 may create opportunity, but it does not make the process free. The homeowners who protect themselves best are usually the ones who start with a realistic assessment instead of guessing.

Red Flags That Signal You Should Start Now

If any of these sound familiar, it is probably time to stop postponing the issue:

• you plan to sell or refinance in the next year
• you want to rent the unit legally
• the space was converted from a garage, workshop, or storage area
• electrical, plumbing, or mechanical work was added without permits
• you have received a complaint, warning, or code notice
• your insurance, lender, appraiser, or buyer has started asking questions
• you are considering “just remodeling it a little more” before figuring out the permit path

That last one is especially risky. New work added onto old unpermitted work can make the situation harder, not easier.

Don’t Wait Until a Buyer, Lender, or Inspector Forces the Issue

Most homeowners do not deal with an unpermitted ADU because they are careless. They deal with it because life moved quickly, the space solved a real problem, and the urgency of the moment outweighed the paperwork.

But once the unit exists, the question becomes whether you control the process — or whether the process eventually controls you.

Critical timing issues include:

• sale and refinance problems surfacing with no warning
• code complaints turning a quiet issue into an active one
• incorrect repair work making the final legalization process more expensive
• documentation gaps causing permit delays when time matters most

Why professional help matters:

• the first step is knowing whether the unit has a viable path
• the second is documenting existing conditions correctly
• the third is designing the right correction scope
• the fourth is coordinating permit work and construction so the project actually moves forward

This is not just a code issue. It is a property strategy issue.

Protect Your Property the Right Way

If you have an unpermitted ADU, garage conversion, guest unit, or backyard living space in San Diego, do not wait until a sale, refinance, tenant issue, or city complaint forces the problem on someone else’s timeline.

Creative Design & Build helps homeowners turn complex property problems into real project plans. We can evaluate the existing space, prepare the plans, coordinate the permit process, and complete the upgrades needed to move the unit toward compliance.

Call Creative Design & Build today at (855) 445-9455 or email [email protected] to schedule your free in-home estimate. We are located at 9275 Trade Place Suite H, San Diego, CA 92126, serve homeowners throughout San Diego County, and operate under License #1045112.