top of page

SLO County Embraces the ADU

“Oh, and it’d be great if it had a guest unit.”

Guesthouses, granny flats, mother-in-law apartments—they’re all essentially what the state and local governments are calling Accessory Dwelling Units, or ADUs.

And that quote is becoming a repeated refrain among homebuyers.

You’ve probably heard the subject of ADUs come up more frequently in the last two years, often in the context of the whole Tiny Homes discussion. While there’s still a fair amount of questions to be answered regarding how to implement Tiny Homes well, the implementation of ADUs is continually being refined and streamlined to make it an increasingly viable option for homeowners.

In 2017, California passed SB 1069, a piece of legislation which essentially squashed any counties’ or municipalities’ attempts to restrict the building of ADUs. California is in a housing crisis, and the streamlining of ADUs is part of a multi-pronged approach to alleviate this crisis.

Among other things, SB 1069 set a deadline for cities to adopt a set of codes which complied with the new law. After the deadline passed, the state’s general rules automatically become the law of the land for any procrastinating cities.

One such procrastinator was Los Angeles, which saw permits for ADUs skyrocket overnight—from around 250 permit applications in 2016, to over 3,800 in 2017!

Obviously there’s strong demand for ADUs.

And SLO County has created a proposal to remove even more regulatory barriers, so more homeowners are free to build ADUs on their property.

Here are a few of the changes the current proposal would make:

Eliminate Exclusion Areas

There are 34 exclusion areas for ADUs in SLO County, including Los Ranchos, a section along Los Osos Valley Road, and a portion of South Atascadero. While some properties will remain excluded, the current proposal would eliminate these exclusion areas, allowing for homeowners in these areas to build ADUs on their property too. This would free up around 17,000 parcels for the addition of ADUs.

Eliminate Non-conforming Development Rule

Currently, the rule is that if a property has a non-conforming development, it is restricted from adding an ADU. For example, if a home does not currently meet the minimum setback requirements from the property line, this property would be not be eligible for permitting an ADU. The current proposal would eliminate this rule, meaning houses which have non-conforming developments would be free to build ADUs too.

Eliminate Additional Parking Requirement

At present, the rule is that if you build an ADU on your property, you are required to provide additional off-street parking in addition to that required for the primary residence. The proposal would eliminate this rule. However, it would require the replacement of any required parking spaces which are removed through the conversion of an existing garage to an ADU.

Minimum Lot Size Reduced

Currently, the rule is that any properties served by community water and sewer need to be at minimum 6,000 square feet in order to qualify for the addition of an ADU. The new proposal would reduce the minimum lot size to 1,750 square feet.

Recent Posts

See All


bottom of page