If you live in CA and interested in building an ADU this is a must read...

Real Estate Agent with Berkshire Hathaway HomeServices California Properties 01238708

 Are you interested in building an ADU (Accessory Dwelling Unit)? Well, you need to get to know the ADU Laws in California.


I will try to give a quick and simple clarification of two of the Laws that went into effect the beginning of the year.

Before I do that, let me just give a bit of history. Before the terminology ADU became the norm, ADU’s were known by other names such as In-Law units, granny flats and backyard cottages to name a few. As time went by, here in California state and local politicians started to create ADU ordinances under the guise of being a solution to help in increasing the supply of affordable housing. This in turn has made the Ordinances different in almost every city and county in California.


When someone asked me about ADU regulations, I would, just simply say, that it is/was like the Wild West of Building Regulations & Ordinances.

 As I mentioned above AB221 went into effect January 1st,2023 and it requires that all cities change their ADU size limits to at least 16 feet. In other words, the height needs to be minimum 16 ft, high. This is basically paving the way for more two story ADUs.  

They have added new regulation in this law which allows to build even higher than 16 feet. For example, if the ADU is attached to the primary dwelling it can be up to even 25 ft high. Needless to say, this still leaves some questions for clarification, such as with the height restrictions how will this impact the maximum size of the ADU? Depending on what the local ordinance is it will affect it is my take.


In addition to AB221, there is also another Law that went into effect SB-897 the same day. This Law was intended as a “clean-up” bill, that supposed to clarify the previous provisions. One of them consists of the fact that many cities prohibit homeowners from developing ADU’s if there is unpermitted work on their property. Fixing  or should I say correcting these issues  to bring them up to code can take a lot of time and money. This in turn would delay the development of the ADU, hence SB-897 eliminates these restrictions and the home owner do not need to fix the violations, before building the ADU.

Keep in mind there are other laws that went into effect reference to grants and financial assistance that could be a post for another time.


These new ADU laws intended to make it easier to build an ADU in the state of California. I am confident that this will create more questions and confusion on how to interpret and enforce the new laws. I will go out on a limb that these changes will do more good than harm, since it has become trendy for politicians to show that they are helping the housing affordability crisis here in California.





Wishing you a safe and healthy life and I look forward to your comments. If you are looking for a knowledgeable, focused and goal-oriented Realtor in the Beverly Hills area who will help you achieve your Real Estate goals, please reach out to me directly! If you are looking for a pet friendly Beverly Hills Realtor who can handle and sell the most difficult properties that no one else could, please reach out to me directly!! If you are considering buying or selling a home, a luxury home, luxury investment real estate, luxury vacation homes, or luxury beach properties in Southern California, Los Angeles, Century City, Westwood, West Hollywood, Beverly Hills, Marina Del Rey, Venice or Malibu, feel free to contact me at 310.486.1002 ( m) homes@endrebarath.com or visit one of my websites at https://www.endrebarath.com I contribute a portion of my commission to local animal rescue organizations. Endre Barath, Jr. Realtor at Berkshire Hathaway HomeServices California Properties DRE#01238708

Comments (13)

Jeff Masich-Scottsdale AZ Associate Broker,MBA,GRI
HomeSmart Real Estate - Scottsdale, AZ
Arizona Homes and Land Group/ Buy or Sell

That law and revisions do sound confusing Endre. It seems like some zoning and land use laws in California may be enforced and others are just ignored. Wonder which this will fall under? The multi story ADUs will be a boost to these new shaftless elevator installations for senior citizens.

Jan 29, 2023 09:48 PM
Endre Barath, Jr.
Berkshire Hathaway HomeServices California Properties - Beverly Hills, CA
Realtor - Los Angeles Home Sales 310.486.1002

Jeff Masich-Scottsdale AZ Associate Broker,MBA,GRI you had me cracking up with your comment, sadly you are probably right:)Endre

Jan 29, 2023 09:50 PM
Debra Leisek
Bay Realty,Inc Homer Alaska - Homer, AK

I cannot imagine all the regulations you have to deal with, it's a good thing your clients have you to help them thru the maze of codes!

When people from CA come here, they are amazed at the lack of rules and regulations and permits to work on their homes or property. We don't even have a city building inspector to check on. Of course, we don't have much of a city either!

We live in 2 different worlds Endre Barath, Jr.   

Jan 30, 2023 12:46 AM
Kat Palmiotti
406-270-3667, kat@thehousekat.com, Broker/REALTOR® - Kalispell, MT
Helping your Montana dreams take root

I am sure homeowners in your area would appreciate knowing you are the guy to ask about these new regulations!

Jan 30, 2023 05:12 AM
Anna Banana Kruchten Phoenix Broker
HomeSmart Real Estate - Phoenix, AZ

Endre I was a bit skeptical when you stated they will look the other way on older non-permitted issues.  Huh? I hear that they want to speed up the building of these ADU's but allowing other non-permitted items to slide doesn't seem like a  good direction to me.  I would be very surprised if they put this into effect here in Phoenix as they're down right tough on non-permitted issues. Fix em first or no permit bucko!

Jan 30, 2023 09:26 AM
Ray Henson
eXp Realty of California, Inc. (lic. #01878277) - Elk Grove, CA

The median height of 16 feet seems pretty arbitrary.  It seems like a very nice single story ADU could be built at a lessor height. 

California does need more housing units.  It just seems like the new laws are not being thought out very well.  I hope you are correct, though, and that these new laws create more good than harm. 

Jan 30, 2023 10:07 AM
Ray Henson
eXp Realty of California, Inc. (lic. #01878277) - Elk Grove, CA

Congratulations! You've been Featured in the BananaTude Group.

Jan 30, 2023 10:09 AM
Endre Barath, Jr.
Berkshire Hathaway HomeServices California Properties - Beverly Hills, CA
Realtor - Los Angeles Home Sales 310.486.1002

Debra Leisek  yes we have too many regulations and sadly some are contradictory, Endre

Jan 30, 2023 10:36 AM
Endre Barath, Jr.
Berkshire Hathaway HomeServices California Properties - Beverly Hills, CA
Realtor - Los Angeles Home Sales 310.486.1002

Kat Palmiotti  thank you for your kind words, Endre

Jan 30, 2023 10:44 AM
Buzz Mackintosh
Mackintosh REALTORS - Frederick, MD
“Experience, reliable, leadership”

Maryland REALTORS is currently backing ADU legislation trying to pass a State wide ADU ordinance. It usually starts in California and spreads east!

Jan 30, 2023 12:43 PM
George Souto
George Souto NMLS #65149 FHA, CHFA, VA Mortgages - Middletown, CT
Your Connecticut Mortgage Expert

Endre we have had a couple of excellent presentations on ADU's at our ActiveRain Weekly ZOOM Meeting, and your blog add additional information on ADU's.  They have more guidelines and restriction then I expected when I first became aware of them.

Jan 30, 2023 06:48 PM
Kathy Streib
Cypress, TX
Home Stager/Redesign

Hi Endre- I'm not a huge fan of so many regulations only because they often benefit the attorneys who write them and confuse everyone else. I'm a bit skeptical of allowing a pass on unpermitted work on an existing structure to allow an ADU. I'm not a builder but I see   problems down the road. 

Jan 31, 2023 10:05 AM
Jeff Dowler, CRS
eXp Realty of California, Inc. - Carlsbad, CA
The Southern California Relocation Dude

Hi Endre:

The issues surrounding ADUs (permitting, etc.) are definitely complex and I suspect there is plenty of inconsistency from area to area in terms of enforcement, what's allowed and what's not, etc. I suspect, as you say, the new laws cause more confusion that they eliminate.


Feb 02, 2023 02:11 PM