An unpermitted garage conversion is living space added without city approval, which can create safety, insurance, and resale problems, but a 2025 state law (AB 2533) now makes it easier to legalize older ones without penalties. If your conversion was built before 2020 and meets basic health and safety standards, you can often permit it. Here’s what unpermitted conversions risk and how to legalize one.
There are endless reasons to convert a garage in Los Angeles. From music studios to offices, man caves to yoga studios, rec rooms or she-sheds, homeowners have been converting garages to other types of spaces forever. In fact, some even add bathrooms and kitchens, creating full-on Accessory Dwelling Units used to house family members or as rental units.
And with home prices high as ever, it should be no surprise that many of these Los Angeles garage conversions are illegal, done without the appropriate permits. Having an unpermitted ADU can lead to fines, legal issues, and the requirement to remove the unpermitted structure. It may also affect property resale value and make it challenging to obtain insurance or financing. It’s important to ensure all regulations are met for a hassle-free experience.
But it’s never too late to get your paperwork straight. To that end, this guide helps give you the information you need to dot your Is, cross your Ts, and properly legalize your illegal garage conversion.
Here at GreatBuildz, a free service that connects homeowners in Los Angeles, Orange County, Ventura or San Diego with reliable general contractors, we get inquiries every day about legalizing unpermitted ADU garage conversion projects – here are some tips to get you started.
Key Takeaways
- With new ADU laws in effect, there’s a 5-year grace period for homeowners to legalize unpermitted garage conversions in Los Angeles without fines, providing peace of mind for those looking to make the process smooth. Legal ADUs enhance property value and can be rented out legally.
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Most garages are eligible for conversion into an ADU, especially if they were permitted when built. However, exceptions may apply based on factors like hillside locations or high-fire areas. Consulting with an architect or the city’s building department and local authorities is important.
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After confirming eligibility and having plans in place, submitting them to the department of building is the next step. Simultaneously, obtaining detailed cost estimates from ADU contractors helps in selecting the right professional for the job.
Unpermitted ADU Los Angeles Garage Conversion: What You Need to Know
Many of these illegal garage conversions have been created in LA and surrounding areas without the necessary permits, and now, a large portion of these homeowners are thinking about legalizing their units. Now that new ADU laws are in effect starting January 1, 2020, the state and city are encouraging people to legalize their Los Angeles unpermitted garage conversions and have given a 5-year grace period to complete this without imposing a fine for illegal garage conversion, etc. So, folks are starting to realize it’s worth the costs to legalize their unit rather than keep ‘hiding’ their unpermitted garage space. A legal ADU can be rented to a tenant without issue and clearly adds value to the property at the time of sale, unlike unpermitted space.
There is some really good news with regard to legalizing unpermitted Los Angeles garage conversions. In a majority of cases, the garage itself is ‘eligible’ to be converted into an ADU. Assuming your garage was permitted when it was originally built, you should be within your right to convert it into an ADU (for a detached garage) and Junior ADU or JADU (for an attached garage). One recent change worth knowing: under AB 1154, a new law that took effect January 1, 2026, a JADU with its own bathroom no longer requires the owner to live on the property. See our guide to the new 2026 ADU laws for details. Even if your garage doesn’t meet current setback requirements from your property line, it should be ‘grandfathered-in.’
There will be some exceptions, like a hillside or high-fire areas, so it’s important to confirm your property qualifies by speaking to either a knowledgeable architect or the city’s building or planning department (in the city of LA, speak with the Building Department, Zoning Section). Another piece of good news with the recent ADU legislation is that you do not have to provide any new parking on your property when converting your garage to ADU.
Let’s discuss the steps involved in legalizing your unpermitted garage conversion. As discussed above, your first step is to confirm your garage is eligible. Once you have confirmed this, the next step is to hire an architect/designer to create the plans for you and meet at least one ADU contractor to discuss the rough scope and costs.
Create a Set Of Plans
The city requires you to create a set of plans for your Los Angeles garage conversion. These plans are drawn to show your garage conversion meeting today’s building codes and guidelines. So, the plans will include such elements as structural and framing details, windows & walls, energy efficiency (title 24), and other notes. An architect will measure your space and create these plans with the help of a structural engineer, as needed. This will be the plan submitted to the city building department to secure a permit. You can expect these plans to cost between $4,000-$12,000. An ADU Contractor can also help with this task.
Meet With Your Contractor
You should definitely meet with an ADU contractor as well. The ADU contractor can look at your garage and give you some ideas/thoughts regarding the costs involved, the construction process, and the potential “unknowns.” Depending on how well or poorly your unpermitted garage conversion was built, there may be a substantial disparity between the costs to legalize. For example, is there insulation in the walls? Is the existing sewer line adequate? Are the foundation footings deep enough? Are there structural/framing improvements that will be required?
Based on what they see, a good contractor can give you a sense of the likelihood and costs of these unknowns. It’s important to know this so you can budget appropriately to legalize your ADU and not be shocked after you create plans and pull a permit.
Submit Your Plans
Once you have some idea of the budget and a set of plans, the next step is to submit these plans to the city building department. In less than 60 days, you should receive a garage conversion permit to start (or corrections to make to your plans). While your plans are in plan check, you can provide them and any other scope of work you want to include to several garage conversion contractors so they can prepare detailed cost estimates for you. Once you select your favorite garage conversion contractor and sign a contract, you’re ready to start construction.
Compare Your Contractors’ Bids
The next step is to compare your contractors’ bids. Be careful not to just look at the price but also carefully compare the scope of work. Bids can be very inconsistent among contractors. Let’s face it: when you meet with three different people, they may hear three different things. That’s why it’s important to carefully review and compare all bids for consistency.
Another thing to look for when comparing contractor bids is the inclusion of material costs. You can be confident that all the bids include the costs of rough materials like lumber, drywall, nails, etc., but there is no standard practice for the inclusion of finish materials like lights, faucets, flooring, tile, etc. Some contractors exclude all of these and have a note that says that the client is responsible for selecting/paying for these materials.
Other bids will have a maximum “allowance” included that covers up to a certain amount for each material. Although it’s not terribly important how each contractor details their bid, you will need to spend the time to ‘spread’ or compare the bids to get to an ‘apples to apples’ comparison. It can be a good idea to start with your own ADU checklist to ensure everything is included.
Start Building Your Los Angeles Garage Conversion
At the very beginning of construction, your ADU contractor will call for an initial city inspection. The city inspector will want to see how your unpermitted garage conversion compares to your plans (and current code), so you might ask the contractor to remove some areas of drywall to ‘see inside’ the walls.
They will be looking to check the adequacy of framing, electrical, plumbing, insulation, etc. They may also ask to see the depth of your foundation footings. Based on what he/she sees, the inspector will issue a set of ‘corrections’ your contractor will have to make to proceed. As we discussed above, these ‘unknowns’ could be minor or major depending on the original construction quality.
The costs can vary significantly based on the existing condition and quality of the ADU. To give you some idea, a brand-new Los Angeles garage conversion to ADU costs approx. $120,000-$150,000. (For comparison, a new detached ADU built from scratch runs $150,000-$400,000.) That number includes taking a standard garage and adding everything necessary to create a dwelling:
- Kitchen
- Bathroom
- Appliances
- Walls
- Windows
- Flooring
- HVAC
- Plumbing
- Electrical
- Structural framing
When legalizing a garage conversion, presumably, some of this work has already been completed and can be saved. So, depending on the extent of work needed, the construction costs of legalizing this space will likely range from $20,000-$70,000.
The Major Costs of Legalizing Your ADU
The cost of legalizing and permitting an ADU can range quite a bit, as discussed above ($20-$70k), and this is largely based on the original quality of the work and when it was completed. The city inspectors will require your ADU to be up to today’s building standards (the building code), and it’s important to keep in mind that property taxes may increase as a result of the value added by the ADU. So, it’s possible that if your work was done recently, much of it could be acceptable (copper plumbing, etc). However, if the work was done long ago, it’s unlikely it will meet today’s building code.
A few items that might require a large portion of the budget are as follows:
- Your ADU waste lines must be connected directly to your sewer lateral in the front yard. If the original unpermitted were instead connected through your main house, it will need to be re-routed.
- An ADU must have an electrical panel and electrical meter, so it is likely this was not done previously and needs to be completed.
- Current building code often requires that exterior walls be shear walls (framed out with plywood). It’s quite possible your existing construction doesn’t include this element and needs upgrading.
- Depending on the age of the structure, your foundation may or may not be deep enough to suffice. If the building is old and the foundation is insufficient, you may be required to install deepened footings or underpin the foundation in some places.
How to Find the Right ADU Contractor to Legalize Your Los Angeles Garage Conversion
It’s best to search for only local, licensed General Contractors. No other contractors are qualified or equipped to do this sort of construction, and using an unlicensed contractor or handyman would be a mistake. Any contractors you contact, always confirm they have experience with illegal or unpermitted ADUs. You’ll want to hire a contractor who has done this before and, therefore, knows the potential issues/pitfalls.
There are several other important criteria you should use in selecting an ADU contractor.
- Check for a valid contractor’s license on the Contractors State License Board website to confirm it is active, there are no disciplinary actions, and it has Worker’s Compensation insurance associated with it (assuming the GC has employees).
- Make sure they’re insured and get a copy of their insurance certificate.
- Ask your contractor for at least three references you can call.
- Read their reviews online on Google & other contractor search engines. If you want more tips on how to find and vet an ADU contractor, check out my blog: 10 Tips To Hire an ADU Contractor
Why Legalize an Unpermitted ADU?
As you can already tell, legalizing and obtaining an unpermitted ADU takes a reasonable amount of time, effort, and money. But, for many homeowners, it can be well worth it. Once you legalize an unpermitted ADU, it adds considerably to the value of your home as it is considered an official part of your property. Also, once you legalize an unpermitted ADU Los Angeles, you can legally rent it out to a tenant and earn rental income. Just remember to make sure to call your insurance agent and tell them that you need to add your new legal ADU to the property coverage.
Common Challenges and Solutions
Below, we look at some common challenges you may come up against when legalizing a garage conversion, offering solutions you can use.
Structural Compliance
Challenge: Unpermitted conversions may lack structural integrity, posing challenges in meeting current building codes.
Solution: Engage a qualified contractor to assess structural requirements and make necessary improvements during the legalization process.
Unknown Construction Quality
Challenge: The original garage conversion’s construction quality may vary, leading to uncertainty in costs and scope.
Solution: Prioritize a full inspection by an ADU contractor to identify potential issues, allowing for a more accurate budget and timeline.
Cost Variability
Challenge: Legalization costs can fluctuate based on the extent of required upgrades and compliance measures.
Solution: Create a detailed budget, considering potential unknowns, and obtain multiple contractor bids for a full cost comparison.
Parking Requirements
Challenge: Previous regulations demanded additional parking spaces, impacting property layout.
Solution: New ADU laws have alleviated parking constraints, removing the need for extra spaces when converting a garage into an ADU.
Permitting Process
Challenge: Handling the permitting process can be complex and time-consuming.
Solution: Hire experienced professionals, including architects and contractors, to assist with permit applications, ensuring a smoother and more efficient process.
Insurance Implications
Challenge: Unpermitted structures may affect property insurance coverage and claims.
Solution: Notify the insurance provider of the ADU legalization, ensuring adequate coverage for the newly legalized space.
New ADU Laws for 2025: AB 2533
AB 2533 is aimed at helping property owners who have unpermitted ADUs or garage conversions built before January 1, 2020. This law requires local building departments to assist these owners in getting permits, as long as the units meet basic health and safety standards. Local agencies must now give owners a list of necessary repairs or upgrades to meet code, and owners can bring in private contractors for cost estimates.
One helpful aspect of AB 2533 is that it prevents local agencies from charging impact fees or connection fees on these unpermitted units if they don’t need new utility connections, making it easier and cheaper for owners to get legal approval.
If you want to learn more about the costs or process of legalizing an unpermitted garage conversion/ADU project in Los Angeles, Orange County, Ventura or San Diego, or if you’re ready to take the next step and talk to a local contractor or designer/architect about your specific project, feel free to call one of our friendly GreatBuildz staff at 818.317.3567 or submit your project at www.GreatBuildz.com.
Check out the GreatBuildz Guide Blog for more construction tips and advice for any type of home remodeling project!
Frequently Asked Questions
1. What is an unpermitted garage conversion?
It’s a garage that’s been turned into a living space without the proper permits or inspections from the city, which can lead to safety, legal, and resale issues.
2. Can I legalize an unpermitted garage conversion in Los Angeles?
Yes – by submitting plans, making code-compliant upgrades, and passing inspections, you can bring your conversion up to legal standards.
3. What are the risks of leaving it unpermitted?
You could face fines, insurance denial, safety hazards, or be forced to return the garage to its original condition.
