County of Marin - News Releases - Accessory Dwelling Units

For Immediate Release
October 16, 2020

ADU Marin Launches for Those Exploring Accessory Dwelling Units

Workbook, website, webinar series helps create new housing on your property

San Rafael, CA – Several new tools are now available for homeowners interested in building an accessory dwelling unit (ADU), also known as a second unit, a granny flat, an in-law unit, or a converted garage. Help is available whether a property owner wants to generate extra income, create more housing for the local workforce, or house more family members.

ADU Marin is a new partnership between 10 local cities and towns and the County of Marin. The group launched a step-by-step website and workbook along with a webinar series to guide people through the process of building an ADU.

An exterior view of an accessory dwelling unit (ADU) in somebody's backyard.Accessory dwelling units, known as ADUs or in-law units, help provide a solution to the housing crisis and generates extra income for property owners. (Photo by Baird+Driskell Community Planning)
The website covers each step of the process, from thinking about building to permits and construction. It features stories from homeowners who have built an ADU and renters now living and working in Marin, along with more than a dozen floorplans. Plus, there is a calculator to figure out what it might cost and what rent could be. The workbook goes deeper into the process and is full of exercises, checklists,  and activities. Whether a homeowner needs to brainstorm ideas, choose a contractor or rent their finished ADU, they will find answers each step of the way.

To introduce the new tools, webinars will be held on October 26, October 29, and November 5, all from 6:30-8 p.m.

  • October 26 – Belvedere, Tiburon, Sausalito, unincorporated Southern Marin. Register online.
  • October 29 – Larkspur, Corte Madera, San Anselmo, unincorporated West Marin. Register online.
  • November 5 Mill Valley, Ross, Fairfax, unincorporated Central Marin. Register online.

Creating more housing options, especially affordable units, has been a top priority of the cities, towns, and County of Marin for years. ADUs are seen as an important way to create more housing without an increase in suburban sprawl.

In January 2020, the Board updated the Marin County Code to relax local ADU construction rules in an effort to encourage more ADU building. Living in an ADU is an enticing option for lower-income residents in one of the country’s most expensive regions in which to live. The cost of housing in Marin, considered a crisis by the Board, is regularly displacing people who have been priced out and preventing people who have jobs in Marin from living close to their workplaces.

“There is a significant opportunity for more growth in accessory dwelling units in Marin,” said Jillian Nameth Zeiger, a planner with the Community Development Agency’s Housing and Grants Division. “We are already seeing moderate growth, but these new tools can assist homeowners in the process and create more homes for our workforce. Having people be able to live close to where they work is not only good for morale and a sense of community, but it’s good for the planet because it reduces greenhouse gas emissions.”

The Board approved extended and expanded financial breaks on building and permit fees for ADUs in unincorporated Marin County in January. As an incentive, those renting out ADUs will have permit fees waived up to $10,000 if they rent to tenants with household incomes below 80% of the local median. In Marin, that translates to approximately $139,000 for a family of four, $125,500 for a family of there, $111,550 for two people, and $97,600 for an individual. There’s a $5,000 break on permits for ADUs that are rented between 80% and 120% of the median income.

Marin has a very low vacancy rate for available rentals, forcing many residents to settle for homes beyond their price range or settle for living further away and commuting. In addition, Marin is still experiencing reverberations in the rental market because of the 2017 North Bay wildfires that displaced thousands of families in Sonoma, Lake, and Napa counties. More recent wildfires could lead to a bigger housing crisis.

On the bright side, more than 70 ADUs have been created in unincorporated Marin over the past two years. Although growth has been slower in local towns and cities, surrounding Bay Area counties are seeing steady increases in the number of ADUs built and now available for rental.

“With housing such a huge priority, there is much more assistance available now than there used to be for people thinking about creating an ADU to supplement their income,” Nameth Zeiger said. “In the bigger picture, we hope people will investigate ADUs as a way to improve the quality of life for our workforce. Providing a home for an individual or family can be rewarding and promote a feeling of community.”


Leelee Thomas
Deputy Director, Housing and Federal Grants Division
Community Development Agency

3501 Civic Center Drive
Suite 308
San Rafael, CA 94903
(415) 473-6697
Email: Leelee Thomas
Affordable Housing webpage