Marin property owners to get ADU planning aid

Marin residents thinking about installing an accessory dwelling unit will soon gain access to increased planning assistance.

A three-year trial merger is underway between ADU Marin — a collaboration involving the county and 10 Marin municipalities — and the Napa Sonoma ADU Center, a project sponsored by Napa Valley Community Foundation, Community Foundation Sonoma County and other entities.

The Napa Sonoma ADU Center was created after the October 2017 Tubbs fire, which destroyed more than 5,643 structures, including 5% of Santa Rosa’s housing stock.

The merger was one of the recommendations contained in a Marin County Civil Grand Jury report released in June. The report urged the county and local municipalities to foster the creation of more ADUs to address the state’s housing shortage.

Jillian Zeiger, a county planner, told supervisors at a meeting this month that in addition to stimulating the development of ADUs, the merger would help the county and municipalities implement their housing element policies.

“We have a program in our housing element to foster the development of ADUs,” Zeiger said at the Dec. 12 session.

The state has mandated that Marin County and its municipalities facilitate the creation of 14,210 new residences by 2031. In its housing element, the county projects that 280 of the 3,569 residences it must plan for will be ADUs.

“By my calculation,” Supervisor Dennis Rodoni said, “we should be building two and a half ADUs a month to meet our housing element goals.”

From 2017 to last year, 180 ADUs were built in the county. The number grew from seven in 2017 to a high of 54 last year.

ADU Marin’s website provides code-compliant floor plans, a calculator for construction costs, a step-by-step workbook and success stories. The new merged entity, which will be called the ADU Center, will include features that are unique to the Napa Sonoma ADU Center. Most notably, the Napa Sonoma center offers one-on-one feasibility consultations and a wide selection of code-compliant floor plans.

“The consultations are designed to help people get moving on their project,” said Scott Johnson, director of the center. “I can’t tell you how many times I’ve had conversations with co-owners where they said, we’ve wanted to do this forever, but now we’re looking at trying to move forward and don’t know where to begin.”

Johnson said his organization researches each prospective property to assess the zoning and ADU regulations governing that location.

“We can talk them through at the very early stages of the ADU process,” he said, “to give them a framework so that they can make an informed, intelligent decision about their project.”

Johnson said jurisdictions such as San Jose and Los Angeles sometimes spend tens of thousands of dollars to commission a few architectural plans of ADUs for their residents to use. Despite the expense, he said, the plans rarely get used because they fail to provide the residents with a sufficient range of options.

“Two or three designs is not a very diverse set,” Johnson said. “They don’t work in all locations. Size and need is different.”

Johnson said his organization asked architects to create designs for it.

“We have 50-plus designs on our current website and then the jurisdictions can sign on and say, we want to pick those five or six or eight or 10,” he said.

The jurisdictions then review the plans for code compliance and can incentivize their use by offering an expedited permitting process and reduced fees.

Johnson said jurisdictions get what they want, ADUs on the ground; architects get the ability to design once and sell multiple times across various jurisdictions; and homeowners get well-designed ADUs at a fraction of the cost of a new design.

In a written report to supervisors, Zeiger said Marin County and participating local cities and towns also want to utilize another Napa Sonoma ADU Center service: a forgivable loan program for people creating ADUs like the one that the organization launched earlier this year in conjunction with Napa County.

The program provides a $105,000 forgivable loan, provided the ADU is rented at or below 80% of the area median income, which is $133,840 for a three-person household in Marin.

“The jurisdictions and staff here are really interested in the loan program,” Zeiger said.

Marin’s housing element states that the county will seek to locate 50% of its ADUs and junior accessory dwelling units in “high/higher resource areas,” where levels of concentrated affluence are the highest.

Although the agreement is being described as a merger, the Napa Sonoma ADU Center will be paid $621,000 to provide Marin residents access to its services for the next three years.

Normally, the Napa Sonoma center charges a fee for its feasibility consultation and permit-ready ADU plans. Zeiger said these services will be free for Marin residents.

The Marin Community Foundation is providing $225,000 to cover part of the cost of the pilot project. Marin County is contributing $154,000 in grant money it received from the Association of Bay Area Governments for countywide housing collaboration. Eight participating municipalities — Sausalito, Fairfax, Corte Madera, San Anselmo, Larkspur, Mill Valley, Novato and San Rafael — will each contribute $30,000.

“This is a great program, and I’m willing to spend the money,” Rodoni said. “I’m just wondering what sort of performance goals we might want to attach to this to make sure it is successful for us. There should be some expectations coming out of this.”

Rodoni said he would like to see a report after the first year of operation.

Supervisor Katie Rice said it will be important to ensure that new ADUs are actually being used as rental housing and not for some other purpose such as an extra bedroom, office space or indoor gym.

Otherwise, Rice said, “I feel like it’s almost a gift of public funds.”

Johnson said the studies he is familiar with indicate that 93% of ADUs are rented and generally at low and very low rates.