With relaxed rules, Calfornia North Bay developers embrace 'granny units'

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Santa Rosa ADUs by the numbers

2017: 33 applications (includes 1 rebuild)

2018: 126 applications

  • 47 fire related
  • 79 new builds

2019: 197 applications

  • 33 fire related
  • 164 new builds

Source: City of Santa Rosa

Easing restrictions by state and local governments is triggering a rise interest in accessory dwelling units. Sometimes called “granny units,” they are usually built on the same lot as a large, primary dwellings.

And while some are designed for use by family members, others are being built to provide rental income. Or units are being built by those downsizing after two devastating wildfires.

Reduced regulatory barriers

A new state law that took effect Jan. 1 removes minimum lot size requirements and reduces setback requirements for ADUs. With this legislation, neighborhood covenants, codes and restrictions can no longer prohibit ADUs on lots zoned for single-family dwellings, increasing the number of properties eligible to have granny units, in-law units and backyard cottages. However, properties must have adequate water and sewer or septic handling capacity in order to have an ADU.

Reporting to the Santa Rosa City Council on Feb. 11, David Guhin, assistant city manager and director of planning and economic development, said that ADU permits spiked higher for both fire rebuild second dwellings and nonfire-related ADU permits submitted in both 2018 and 2019 in Santa Rosa following the Sonoma Complex and Kincade fires.

As of Jan. 1, Guhin said five ADU applications have been received, 140 ADUs are in various review stages, 59 are under construction and four have been completed.

The report said this increase was due in part to the reduction of city impact fees, as a result of deed restriction affordable contracts in 2018 as well as relaxed building codes resulting from state ADU legislation adopted in January 2017.

That year, Santa Rosa city permitted 33 ADUs (1 rebuild). In 2018 there were 126, 47 fire related and 79 for new builds. In 2019, 197 permit applications were received: 33 fire related and 164 for new builds.

Guhin also revealed that city housing production for 2019 totaled 1,049 units. This year 1,496 additional units are under construction, with 1,689 building permits in various review stages, including 916 single family units, 633 multifamily units and 140 ADUs.

This is the highest total seen in at least 15 years and includes both fire and non-fire-related housing, Guhin said.

Jessie Oswald, Santa Rosa’s chief building official, said his organization is working with two companies developing what could become pre-approved ADU plans. One focuses on modular steel construction, and another uses premade wall sections that could be offered to property owners as alternatives in the future.

“One firm offers four different models, and another has five or six ranging in square footage from 270 square feet to 750 square feet,” Oswald said. “This would give property owners the ability to literally plop something down in their back yards with a faster turnaround. We’re committed to studying such methods to increase opportunities and expediency.”

Zoning permits eliminated

Permit Sonoma, the county’s consolidated land use planning and development permitting agency for unincorporated areas, will no longer require zoning permits for ADUs, but building permits are still required along with any applicable related septic and grading permits, according to a county news release.

In January, Permit Sonoma reported that four ADU applications were submitted, nine permits were issued and six ADUs were completed. For all of 2019, there were 87 applications, 58 permits issued and 47 completions. Since the 2017 wildfire, 143 ADU permits were issued in the county, not including fire rebuilds on 164 ADUs for which permits were issued.

Santa Rosa ADUs by the numbers

2017: 33 applications (includes 1 rebuild)

2018: 126 applications

  • 47 fire related
  • 79 new builds

2019: 197 applications

  • 33 fire related
  • 164 new builds

Source: City of Santa Rosa

“Website numbers show growth in ADUs is kicking up in response to efforts to reduce requirements and a strong desire to increase housing production and density in the county,” Director Tennis Wick said.

Sonoma County’s new code encourages the development of detached and attached smaller “cottage-size” single-family homes within existing low- and medium density-urban residential neighborhoods, Wick said. The minimum parcel size is 8,000 square foot in urban service areas served by public sewer. One reserved parking space must be provided per unit plus one additional space for every three cottages, with parking provided in a common area. With this plan, one cottage could be built for every 2,500 square foot of lot area. The total building square feet for a cluster of three cottages is 2,700 square foot, unless a use permit for a larger size is allowed after a design review.

This means that three 900-squar- foot cottages could be built on the same 8,000-square-foot lot. An additional requirement calls for a minimum of 200 square feet per unit of open space. Of that, 60 square feet may be private, with the rest allocated for open space.

Permit Sonoma is also working on a “permit-ready” ADU model, where processing time would be minimal with no discretionary reviews, but the prime focus would be on construction costs and financing, Wick said.

“With this model, we want to take a huge part of the regulatory process out of the equation,” Wick said. “The proposed model would already be reviewed and plan checked leaving only having to affix the unit to the ground and address water and septic issues. We must find creative financing solutions for ADUs, that can cost upwards of $100,000 or more, by working with credit unions, banks and the Community Development Department to make this possible, especially for retirees and those nearing that point in life.”

In Marin County, senior planner Steve Stafford in San Rafael said 87 ADU permit applications have been received in Marin over the past four years: 30 in 2017, 33 in 2018 and 16 in 2019 with seven more so far in 2020. He said that includes about a half-dozen JADUs per year.

“Every year the state primes the pump with to help make the ADU process work better,” Stafford said.

In Napa County, an updated housing report as part of the general plan will be finalized by March. Jason Williams, chief of the Napa Building Department, said they see an average of eight to 10 ADU applications a year.

He noted that while subdivisions are being built in urban areas of Napa County, there are no new subdivisions in unincorporated county areas where the focus is on agriculture and the wine grape growing industry. However, “guest houses” have been built on multi-million-dollar wine estate property.

Development increases density

The combined detached-and-attached ADU Cottage approach is already been applied by some contractors, such as Michael Wolff, principal of Wolff Contracting in Santa Rosa, who is also building other ADUs for his customers.

“I bought a lot in the Coffey Park area on Dennis Lane and built a 1,196 square foot ADU for my retired father that will be ready for occupancy by May 1, and also plan to build my own home with a JADU on the same parcel,” Wolff said.

A junior accessory dwelling unit is limited to 500 square feet, while an ADU can be up to 1,200 square feet.

He said, in his experience, “the state has been bending over backwards to make it easier to navigate the ADU process which can be intimidating at first, and our county is also doing more to make the process more accommodating.”

“If a JADU is attached to a house, costs are typically reduced because you are benefiting from sharing existing walls and roof. But some rooms are more expensive, such as kitchens and bathrooms,” Wolff said.

Cost per square foot can be about $300 a square foot for JADUs and $500 a square foot or higher for ADUs, he said. But Wolff brought his ADU in for about $290 per square foot.

In Sonoma County, high-end estate home builders, such as Santa Rosa-based Jim Murphy and Associates, say their clients are also adding guest houses and pool houses with living space. Some large units range from 950 to 2,000 square feet.

Steve Ronchelli, president of Jim Murphy & Associates, said they have built “zero ADUs,” but the company is building guest houses for almost every estate home client. Three are under construction now, plus a half dozen in the past.

David Schroeder with Nordby Construction confirms that this is also true for some of their clients.

York Saccomanno, a founder of Kirby Construction, also in Santa Rosa, said interest is there among customers and potential clients for ADUs. In rural areas, installation of septic systems is an issue, but new permits for rebuilding after the fires often include accessory units.

Different ADU development models are also emerging, according to Brent Stewart, head of Stewart Construction Services of Rohnert Park.

“We’ve done a number of ADUs,” Stewart said. “Years ago, I started out in construction flipping houses — existing units, upgrading them and putting them up for sale as quickly as possible. Looking back, it occurred to me that should have added accessory units to these properties.”

Stewart now believes the house flipping model should include the addition of ADUs or JADUs to increase property values, selling prices and/or rental fees, at a time when living space is in short supply.

For Orrin Thiessen, developer of the Green Valley Village in Graton, combining a detached ADU above two-car garages built behind seven new homes was a key to success for this project.

“People love these homes, the community green and Redwood trees along a creek, but wanted ADUs for additional income,” Thiessen said. “We built 550-square-foot ADU units finished with stainless appliances, stacked washer-dryer, bamboo flooring and Berber carpeting. These one-bedroom full bath with shower stone tiles and a living/dining room adjacent to a well-appointed kitchen.”

EDITOR'S NOTE: This story has been changed to reflect that in 2017, Santa Rosa permitted 33 ADUs, including one rebuild.

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