The Latest ADU Regulations In San Diego You Need To Know

Hi, I'm Sean Canning, principal architect at Ten Seventy Architecture. We're one of the leading experts in San Diego's accessory dwelling unit regulations. And today I just wanted to make a quick video to explain one of the more significant changes to the Municipal Code, which is going to affect your ADU and JADU designs.

So let's start off by just reading the code and then we'll go back and try to understand exactly what this code means and how it's going to affect our projects.

So this is in subsection capital E under the ADU and JADU regulations and the municipal code.

It says "ADU and JADU these structures must comply with the front yard and street side yard setbacks of the base zone. Interior side yards and rear yard setbacks for new ADU and JADU structures shall be provided as follows."

And then there's two subsets here. There's a section lowercase i and then there's another section, double lowercase i. So let's start with the first one right now (lowercase i).

"One story ADUs or JADUs with the structure heights 16 feet or less may observe a zero foot setback at the interior side yard and rear yard."

Okay, so this is exactly the way it was in the code previously. And basically what it's feeling is that if you're proposing an ADU that is one story or 16 feet or less. Then you basically can build a zero lot line condition on your side yard and rear yard. But here's where it gets very interesting.

This is subsection double lowercase ii: "One story ADUs or JADUs with a structure height that exceeds 16 feet and multi story ADUs or JADU structures may observe zero foot interior side yard and rear yard setbacks unless the side or rear property line abuts another premises that is residentially zoned or developed with exclusively residential uses, in which case a four foot setback shall apply.

Okay, this is very interesting, particularly to myself, because I'm actually filming this video in the Prince House ADU which is built with a zero lot line condition. And it's a two story structure.

So you would no longer be able to build this particular project that I'm sitting in right now.

Okay, but let's break this down a little bit more. So this really only applies if you have a condition where it's over 16 feet - so you'd have to be at like 16 foot one inch before this would kick in, or a multi story project.

You also have to have an adjacency of a residential zone or residential use. And it actually specifically states exclusively residential uses. So that could mean if there's a mixed use project on your neighbor's lot and you would be able to build right at the lot line.

Okay, so there's a couple of things I want to break down again.

First off, the code language uses the term "structure" which is a defined term in the municipal code. Structure is basically defined as like an entirety of one building. So if you were proposing a duplex with a lower level unit and an upper level unit, both floors, both units, would have to have this four foot setback and there's really no work arounds in that in that part of the code.

Okay, the second thing I want to mention is what happens if you have a three foot base zone setback.

So some of the more dense residential zones. on the more narrow lots like this one where I only have a 25 foot wide lot. actually has a three foot side yard setback.

So it's not explicitly written in this code, but I did reach out to the deputy director of the DSD and he stated that if you have a base zone side yard setback of less than four feet, you're able to use that base zone side yard setback. So in this case, I have a three foot setback here. So I can do two stories, or more, potentially at a three foot side yard setback.

There's one other little loophole here and that is the bay window encroachment loophole.

So if you look into the bay window section of the code, bay windows are allowed to encroach a little bit beyond the base zone, side yard setback so you can use that to get a little bit more square footage if you're really in a pinch or if the design calls for it.

So that's basically a breakdown of one of the more critical areas of the new ADU and JADU code. If you have any questions about this, please feel free to look through the rest of our catalog of videos or reach out to me in an email at Sean@1070 architecture.com.