I’ve been getting a ton of questions lately about accessory dwelling units, so I wanted to talk through some of the bigger issues. Skim to questions that sound interesting or take some time to read. Enjoy if you wish.

What is an accessory dwelling unit (ADU)?
There are lots of definitions out there. In short, an ADU is typically a detached or attached dwelling unit meant for independent living, so it includes a sleeping area, bathroom, and cooking area. California, Sacramento County, and other areas may describe ADUs a little differently. 

If a unit doesn’t have a kitchen is it an ADU?
An ADU must have a cooking area. Otherwise we’d call it something else. Personally I’d probably call it a casita, but that’s just me. Anyway, if a builder constructs an “ADU” and it only has a bedroom and bathroom without a kitchen, we just wouldn’t call it an accessory dwelling. 

WEEKLY MARKET UPDATE: By the way, here’s my weekly video market update called Why aren’t home prices dropping? Watch below or here.

Is my pool house an ADU?
Probably not. Remember, if the pool house doesn’t have a kitchen, bathroom, and there is no sleeping area, it clearly doesn’t qualify as an ADU. I think sometimes if we step back and recognize we’re calling something a “pool house” too, that’s probably a clue that it’s something else.

What other words are used to describe an ADU?
There are countless words such as granny flat, casita, in-law quarters, mother-in-law apartment, garage apartment, etc… This could vary from market to market and person to person.

Is it okay to lump the square footage of the accessory unit into the square footage of the main house?
No. This happens all the time in real estate listings, but if you have to step outside the house into something else, it’s really not proper to include that other space in the square footage of the main house per ANSI standards. Think about it logically too. Imagine a 1,600 sq ft home with a 400 sq ft ADU. Is this really a 2,000 sq ft house? Nope. Maybe the market will pay the same price as other 2000 sq ft homes, but that’s beside the point because we’re fundamentally dealing with a smaller home with an ADU rather than one larger home. These are two different things, right? The problem becomes if we only choose 2,000 sq ft comps we haven’t really proved what a 1,600 sq ft home with an ADU is worth.

What if the square footage in a listing includes the ADU?
We see this quite a bit. I get it because the listing is advertising the total size of all structures on the lot. I just hope there is an asterisk or explanation somewhere in the listing that the square footage represents both the house and the accessory unit. This is important for clarity, maybe liability, and it helps appraisers be more informed when choosing comps. In short, just because it’s listed a certain way in MLS doesn’t mean the market or appraisers will recognize all the space as gross living area.

What if Tax Records shows the ADU in the square footage?
That happens. But just because Tax Records shows the property as 2,000 sq ft doesn’t mean that is what is legal or the way the market sees the units. If you want to know what is permitted it’s probably a good idea to rely on the building department (and hopefully they have good records).

It’s an ADU because it looks like one, right?
It’s key to understand what something is. I recall a unit permitted as a residential office even though it looked like a full-fledged second living space. It had a kitchen, bedroom, and bathroom, but the one thing it lacked was a permit to be an ADU and to be rented. This is where permits matter greatly. If it looks like a duck and quacks like a duck…. Well, it’s not always a duck when it comes to being an accessory unit. An owner might say, “This was fully permitted.” But the real question is, “What was it permitted as?”

How do you value a property with an accessory unit?
That’s a big question. I wrote a separate post about that. In short, I would look at it like a puzzle and consider lots of factors including comps, rental income, and lots of other logical points. 

How many accessory units can one property have in California?
On a single family lot you are allowed one ADU unit as well as one JADU (Junior Accessory Unit at 500 sq ft max). Here is an informative piece from CA for Homes. Please check code in your local area of course too.

Is a single family home with an ADU considered a duplex?
No. There is a difference. I wrote about that here. The struggle is how the lending community and appraisers talk about accessory units vs full-fledged two-unit properties isn’t always the same as the way a city or county thinks about these units. There is also a value aspect to consider. Typically each unit in a traditional two-unit property contributes very significantly to the value whereas as an accessory unit is often “accessory” to the value. In other words, an ADU might not sway value as much for a single family home compared to say taking away one of the units in a traditional duplex.

How do you find comps?
This gets a little tricky because in MLS these units are often called a range of things. Personally I search the property description field and I’ll see what comes up when I type in words like granny flat, accessory unit, ADU, second unit, in-law quarters, etc… Sometimes I even search for two homes on one lot because these units are sometimes listed that way. However, in a map search in MLS you can go to the “other structures” field and then select “guesthouse.” That’s what I did in the image below and look how many properties came up when looking at the past five years of sales. Granted, some of these pins aren’t truly accessory dwellings because they’re a pool house, bonus outbuilding, she-shed, etc.., but this is a great start nonetheless.

What about CC&Rs and rent?
In some areas an accessory unit might not be able to be rented per CC&Rs. If California law has recently superseded this, someone can let me know (people have been emailing me to say California law has, but I haven’t seen anything definitive yet to show these units can be rented (I will update this portion of the post when I hear more)). Otherwise I’ve encountered scenarios where a neighborhood’s CC&Rs will mandate a guesthouse can only be occupied by family members and is not allowed as a rental. I’m not a lawyer, so I cannot speak to any legal issues. I’m just saying before advertising a structure’s rental income in a listing or appraisal, be sure you know the structure can be rented. This might affect value, right?

What do you think about an ADU assessed at the cost of the unit?
I see this happen quite a bit. This isn’t a knock at any Assessor of course. It’s possible that buyers would pay the full cost to build in the resale market, but very often the market doesn’t pay dollar for dollar. In short, if you feel the assessed figure is too high you’re going to need to find out the process to dispute the assessment and show market support for your value opinion. Keep in mind I’m talking about a brand new accessory unit because when it is built you’ll get a supplemental assessment in the mail. As always, if there is nothing to argue, don’t argue. If you do feel value is off though, then be diplomatic and support your opinion with data. Or hire a local appraiser to illuminate market data (the appraiser cannot be an advocate for you though).

I hope this was interesting or helpful. Thanks for being here.

Questions: What else do you wonder about ADUs? Or if you work in real estate, what do you get asked? I’d love to hear your take.

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