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Efforts to ease Accessory Dwelling Unit building process continue in Napa County

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Homes-Accessory Dwelling Units

Accessory Dwelling Units, or ADUs, are also know as granny flats, in-law units or backyard bungalows.

Approvals for Accessory Dwelling Units, touted by lawmakers as one way to help solve California’s housing crisis, have been picking up across Napa County and California over the last few years.

Still, the need for housing units still remains astronomically higher in California than what the slowly increasing number of ADUs can provide for. California has a housing shortage of about 2 million homes statewide, according to a 2018 state report, while the number of ADU approvals statewide have averaged roughly 11,000 annually over the past few years.

Even so, efforts to smooth the ADU application process and spur interest in developing the units among local residents are ongoing, in the hopes that ADUs will help solve at least a small share of the housing crisis. 

Accessory Dwelling Units are, at a basic level, separate, self-contained living units that can be attached or detached from single-family homes. ADU development has boomed in recent years as a result of state laws that sped up and eased the approval of such units at the local government level. 

But easing approval of permit applications doesn’t help residents figure out if they want to build an ADU in the first place. The mission of the Napa Sonoma ADU Center is to help close that information gap, said Renée Schomp, director of the center. It started up in 2020 through a joint effort from the Napa Valley Community Foundation and Community Foundation Sonoma County, she said, both of which were concerned about housing affordability in the North Bay.  

CEO Terence Mulligan said the foundation considers a lack of workforce housing to be a primary driver of poverty in Napa.  That’s because many people who work in Napa pay a large percentage of their income on rent, he said, and therefore struggle to afford other necessities.   

Rental housing, in general, can also be difficult to find, given that the city has maintained less than a 2% rental unit vacancy rate in recent years, which is considered a severe shortage.

Mulligan said ADUs may help improve the situation because they're generally affordable to low- or moderate-income households as rental units — they lease for about 20% less than traditional apartments because they tend to be smaller and offer less privacy, he said.

Schomp said the ADU center was founded after research from the Terner Center for Housing Innovation at UC Berkeley indicated that providing community members information and technical assistance would likely significantly increase local ADU development.

The center now provides a wide swath of services to help people figure out whether they actually want to build an ADU and what their options are for doing so.

Services offered by the center include a calculator to assess the price of building an ADU in various North Bay jurisdictions, free feasibility consultations and regular webinars which cover topics such as types of ADUs, how to finance an ADU and how to create an ADU permit application.

“I can’t stress enough simply the importance of proactive outreach and community engagement,” Schomp said. “Marketing, outreach and community engagement is a huge piece of what we do.”

All this support is necessary in part because of the high cost of constructing an ADU, which may represent one of the largest financial investments of someone’s life, said Mulligan.  

“This is real money we’re talking about,” Mulligan said. “Like, until the cavalry comes along and someone invents a 3-D printed, code conforming, mid-century modern place that would satisfy my wife and would only cost $75,000, this will still be a practice largely of people who have resources.”

One effort to help open up the financial side of building an ADU to a greater number of residents is a partnership between the Napa community foundation and Redwood Credit Union for a construction loan program specifically for ADUs.

Pre-approved ADU plans are another upcoming effort that could help lower costs and speed up ADU permit approval and construction time, Schomp said. In theory, a gallery of designs will eventually be available for people to choose from; all would already be approved by city planning departments responsible for ADU approval, cutting down on the time they need to spend looking through the permit applications.

“The policy is one thing, process is another,” Mulligan said. “It’s not easy if you’re not a professional. If you’re a citizen and you’re turning up at to check in and see if you’ve met the planning requirements, it’s super complicated. We hope the pre-approved or the permit-ready plans will help citizens be better able to pursue an ADU, and it should make it easier for the building and planning departments.”

It remains to be seen how large of an impact the efforts of the ADU Center will have on Napa’s housing crisis, Mulligan added. So far, the ADU center has helped 335 homeowners figure out ADU projects since launching. 

But housing affordability in Napa needs to be solved, Mulligan said. If it isn't, Napa's local economy will be served by an increasing number of commuters, he added, exacerbating environmental and traffic problems among much else.

“We have to get this right, otherwise the precious and vibrant economy that we all enjoy may not be here in the same way in a period of years,” Mulligan said. “A future in which 75% of our workforce commutes in every day from more affordable places is not one in which most of us want to participate.”

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