At the moment, only certain areas of the North Bay have created an environment where residential property owners want to build Accessory Dwelling Units (ADUs). Improving financial conditions for ADU construction and occupation will require local and regional collaborations—especially as costs for labor, materials and residential insurance continue to rise. “2020 opened the floodgates by creating a market for this type of housing,” says Scott Johnson, director of the Napa Sonoma ADU Center. “Now we’re fine-tuning local laws and programs to motivate building.” Adds Johnson: “The two main tools for cities and counties are reducing regulation and offering financial incentives.” The Napa Sonoma ADU Center is a nonprofit that offers resources such as feasibility consultations and cost estimation calculators, serving both local governments and residential property owners. Making these tools readily available and up-to-date helps both parties partner on solutions. Residential property owners across the North Bay use ADUs for a wide variety of purposes, from home offices to long-term market rentals to housing for family members with intellectual disabilities. Typically, property owners cannot construct ADUs for short-term rentals. County and city regulations often prohibit or severely limit this use. Between 2020 and 2025, the State of California enacted laws that dramatically improved the landscape for ADU construction and use. These laws eased restrictions and added flexibility. Changes include allowing ADUs attached to a main structure to be built up to 25 feet and requiring permitting agencies to explain deficiencies in applications within 60 days. “The state did so much so fast that cities and counties are still catching up,” says Johnson. “They are looking for ways to streamline and improve permitting processes even further.” One of the most popular local programs to support ADU construction is Napa County’s Affordable ADU Program. This is a loan-forgiveness program that provides up to $105,000 in forgivable loans to property owners who rent ADUs. The program requires that a lease for an ADU offers affordable housing. The ADU of Rick and Lacey Boatman on their property in Napa County. At right, the ADU being lowered onto the site by a work crew. [Photo courtesy Napa Sonoma ADU Center]
Another program of note is the City of Napa’s Junior Unit Initiative Program. This program offers up to $50,000 to property owners who rent junior ADUs (JADUs). A JADU is defined as a unit 500 square feet or less that is contained entirely within a single- family residence. One example is a converted garage. “The large amount of ADU construction in Napa County can be traced back to [the county program]. It relies on state funds that in turn free up county general funds. To be eligible, the property owner must commit to renting long-term to a tenant with an Area Median Income of 80% or less,” says Johnson. The cost to build and insure The biggest cost associated with an ADU is that of construction. In the North Bay, this typically ranges between the mid $200,000s to over $600,000 for a structure between 400 and 1,200 square feet. It usually takes between six months to a year to construct an ADU. The whole process from design to move-in typically takes between 18 months and two years. Often, it is more expensive to build an ADU from the ground up. The cost of construction can be lower if a property owner remodels an existing structure like a detached garage to create an ADU. “A remodel or [the] addition of an ADU usually involves older existing structures, which can make the designs a little more challenging. Sometimes a property owner can save money by utilizing an existing component of a primary residence, like the existing electrical meter,” says Michael Boehme, principal for MB
46 NorthBaybiz
April 2025
Made with FlippingBook. PDF to flipbook with ease