ADU, AIACA, Housing, Relevance|

By: Michael Malinowski, FAIA

Accessory Dwelling Units in California were significantly affected by a number of new laws that went into effect on January 1st 2020. Given that these laws were officially approved only a couple of months prior to the effective date, it is likely that across California’s approximately 500 jurisdictions there are going to be variations in interpretation and action. In the meantime, architects are seeing increased interest in ADU’s, which is welcome at a time when conventional housing production continues to decline, even in the face of chronic and critical shortages. The disconnects architects face in this kind of unsettled environment can quickly become expensive and time consuming problems for our projects and our customers.

Sometimes there can be major differences between adjoining jurisdictions. One example: in the Sacramento area, the City of Sacramento adopted an emergency ordinance in December of 2019 that moved past the provisions of state law in a number of ways, such as allowing 2 full ADU’s for both single family and duplex properties. In contrast, the County of Sacramento issued an advisory which only indicated a single ADU was permitted, and referenced development standards that included story limitations, particular attachment requirements and siting for ADU entryways; and setbacks which varied from the new statewide rules.

Faced with a project that was being derailed, our office was proactive in sorting things out. We started with an in person meeting with the senior planner who worked on the advisory memo. It was cordial, but didn’t clear up what we felt were major misunderstandings, so we followed up with written comments Within a couple of weeks, the County issued a new advisory, outlining and correcting the earlier misunderstandings.

It seems likely that scenarios such as this might be surfacing elsewhere, and in that light, I’d like to encourage sharing anecdotes and perhaps even exhibits, as it could potentially save others time and efforts, while fostering support between each of us within local advocacy arenas. An additional note: AIA California updated the web site to reflect the new laws, which impacted just about every page in one way or another. As many of you know, some interpretations are still a bit up in the air, as California’s Department of Housing & Community Develop has just now released a technical advisory memorandum. Even with that there will still be some sorting out occurring

over the next few months. One area to keep an eye on is the issue of fees, as this was addressed in a general way in the law. How that ends up being interpreted may vary fairly widely. I’ve personally already seen one jurisdiction state that asking for a street widening, and curb/gutter/sidewalk, for an ADU project was not an impact fee subject to the 750 square feet exemption. Once I hope that at some point HCD provides additional details on this topic so we can see greater constancy in application.

As a steering committee participant who helped AIA CA develop the resource for the public, I hope that homeowners will find the new ADU law information helpful. I hope it inspires them to contact a local architect to construct their own ADU. We’re all still learning California’s interpretation of these laws, so please help us provide the most updated information to the public by letting us know if new or more information can be added to the website by emailing

Michael F. Malinowski FAIA February 12, 2020

AIA California
AIA California
Celebrating over 75 years of service, the AIA California actively promotes the value of design and advocates for the architectural profession. AIA CA is an association of 11,000 dedicated and passionate members who share a commitment to design excellence and livability in California’s natural and built environments.

Comments are closed.

We use cookies to personalize content, to provide social media features and to analyze our traffic.
By continuing to use this website, you consent to the use of cookies.