San Diego ADU Regulation & Permitting Requirements

San Diego ADU Regulation & Permitting Requirements

ADU San Diego allows for a detached ADU with a maximum of 1200 sqft. ADUs up to 800 sq ft are not subject to lot coverage requirements. (This means you can construct an ADU with this size when you’re not covered to the max on coverage requirements for lots ).

What’s the Minimum Height in An ADU Located in San Diego?

The maximum height of a detached ADU is usually at least 16′ and still has reduced setbacks of 0 on the sides and backyard. 

You may construct higher than 16 inches at the height of San Diego, subject to the maximum heights allowed by the zone in question and with a maximum of four feet rear and side and back setting backs (specifically “if you live on the rear side of your property or if that property line runs alongside a different area that is residentially zoned or constructed with only residential purposes .”)

The maximum building height for buildings in San Diego for most residential properties is between 24′ and 30′. Some go as high as 35′. (SS131.0444 An angle-shaped building envelope Plane/Maximum Building Height for the Residential Zones ).>

Do You Have the Ability to Build a Two-Story ADU within San Diego?

Two-story ADUs are permitted to be built in San Diego, per the above information on the height requirements. However, in the case of ADUs situated above garages or any other building accessory to it, the maximum height that flat-roofed buildings can be constructed can be 21′, and the maximum structure height for sloped-roofed structures is 30′ (SS141.0307 (f) Guest Quarters or Habitable Accessory Buildings). 

It is essential to note it is there is a requirement that the City of San Diego requires the staircase to be at least 5′ away from their property line. 

And additionally requires, two-story structures located on the property, which is located adjacent to residential property, must comply with the setback of 4. Find out more about setback and fire rating specifications.

What Size Can the Connected ADU Get in San Diego?

The area for any adjoining ADU San Diego cannot be more than 50% of the original living area, or 1,200 sqft, or less, but it must not be less than 800 square feet.

Can You Create an ADU that has an Attached JADU?

It is possible to construct a JADU. The city of San Diego permits the construction of an accessory dwelling unit (JADU) attached to the ADU However. The JADU must be incorporated into one of the accessory structures. An excellent example of what could be permitted is to build a 1200 square foot ADU with an attached garage that is 500 sqft and then convert the garage into a JADU. We brought this idea with city planners in the City of San Diego in April 2022 to an associate planner who confirmed that the codes allow for this, provided that the detached accessory structure exists and is allowed.


What’s the Minimum Setback to An ADU Located in San Diego?

ADUs must comply with the setbacks for front yards, including the side yard being 0′ and rear setbacks for ADUs as high as 16′ height. That is, it is possible to build to the property line.

But, the crucial point is that if your property is more than 5 feet from your property line, the building code stipulates that the structure be fire-rated, which could increase your construction cost by a few thousand dollars. 

Additionally, we need the clearance of at least 4 feet from structures located on property lines to make it easier to work on construction (it may be feasible to construct closer than this. However, it’s more costly since it requires more manual work). 

This is why we suggest allowing more than a setback of 5′ whenever possible. This will lower the chance of being required to present an inspection to verify that your ADU’s whereabouts are permissible.

Finally, all staircases must be at most five feet from the property line within San Diego. The city of San Diego.


Does San Diego Require Coastal Development Permits?

Yes, ADU San Diego constructed in the coastal development zone are required to obtain the coastal development permit (CDP). This procedure has been changed recently. On September 7th, 2022, the California Coastal Commission certified (W15) the City of San Diego’s changes to their Local Coastal Program (LCP). The city’s staff now ratifies plans. 

They cannot be appealed before the city council, Planning Commission, or City Council, provided they comply with the existing Zoning and construction regulations. However, there are still some rules, and this will all take longer and cost more. We don’t know what the procedure will look like in San Diego because it has yet to be established. 

However, it will be a lengthy and more costly standard ADU submission that will have more documentation and requirements to ensure that the rules of the coastal zone are not protected or preempted under the state ADU law.