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New state laws make it even easier to build an ADU!

Great news: As of January 1, 2020, California passed new state laws that make it easier than ever for homeowners to build ADUs.

If a local jurisdiction has ADU rules that are more restrictive than the new state laws, the state laws overrule those more restrictive local rules. Local jurisdictions are working as we speak to revise their local rules to make sure they align with these new state laws.

Check out this recorded webinar hosted by the nonprofit Generation Housing featuring the Napa Sonoma ADU Center along with expert Planners from the City of Santa Rosa and Sonoma County to learn more, and read on for even more details!

Click this link for a Glossary of ADU terms.

SOME HIGHLIGHTS:

  • ADUs can now generally be built on any lot with an existing, or proposed, single family or multifamily building in a residential or mixed use zone regardless of lot size.

  • BOTH a detached ADU and an interior Junior ADU (JADU) can be built on a single family lot.

  • Freestanding and attached ADUs are allowed up to 800 square feet (sf), up to 16 feet high, with at least 4 feet side and rear yard setbacks. Construction standards apply but not typical zoning standards (i.e., lot coverage, floor area ratios, or open space).

  • No setbacks will be required if the ADU is the conversion or replacement of an existing legal structure such as a garage or shed that is closer than 4 feet to the property line.

  • No impact fees will be charged on ADUs that are less than 750 square feet (sf). If the ADU is larger than 750 sf, impact fees (for roads, parks, etc.) must be proportional to the main house. Permit fees can still be charged.

FULL SYNOPSIS OF THE NEW LAWS:

Allowed Locations:

  • ADUs can now generally be built on any lot with an existing, or proposed, single family or multifamily building in a residential or mixed use zone regardless of lot size.

  • BOTH a detached ADU and an interior Junior ADU (JADU) can be built on a single family lot.

  • At least 2 ADUs can be built on a multifamily or mixed-use lot. This can include:

    o   Option A) Two detached ADUs (up to 800 sf, up to 16 feet high, with at least 4 feet setbacks) 

    o   Option B) Non-living space can be converted into ADUs up to a quarter of the existing apartment count. 

    o   Homeowners can choose to build Option A or Option B. Local jurisdictions can also allow homeowners to do both options.

    o   Junior ADUs are not allowed.

  • Homeowners associations cannot ban ADUs or JADUs, regardless of any existing rules or covenants. However, HOAs can set reasonable design guidelines for ADUs and JADUs.

Application Process, Fees, Occupancy Restrictions and Amnesty:

  • An ADU will be approved automatically by the local jurisdiction – if it meets standards, it must be approved without any public hearings.

  • Jurisdictions have no more than 60 days to review an ADU application.

  • No impact fees will be charged on ADUs that are less than 750 square feet (sf) in size. If the ADU is larger than 750 sf, impact fees (for roads, parks, etc.) must be proportional to the main house. Permit fees can still be charged. (Note: Local jurisdictions are generally still charging school impact fees. Long-standing state law says schools cannot charge fees for units under 500 sf.)

  • Charges for upgraded utility capacity must be proportionate to the new demand.

  • ADUs that receive building permits between 1/1/2020 and 12/31/2024 are exempt from owner-occupancy rules. JADUs still require owner occupancy.

  • If an ADU was built without permits, there is a 5-year stay of enforcement on the unpermitted ADU if it meets zoning, health & safety standards.

Unit Sizes and Design Standards:

  • Jurisdictions must allow freestanding and attached ADUs are up to 800 sf in size, up to 16 feet high, with at least 4 feet side and rear yard setbacks. Construction standards but jurisdictions cannot deny based on certain zoning standards (i.e., lot coverage, floor area ratios, or open space).

  • No setbacks will be required if the ADU is the conversion or replacement of an existing legal structure such as a garage or shed that is closer than 4 feet to the property line.

Parking:

  • Most homeowners will need to provide no additional parking for the ADU, and no one will need to provide more than one unit. 

  • No replacement parking is required for ADUs that are created through the conversion of a garage.

  • No new parking is required if existing space is converted to build the ADU, or if the ADU is within ½ mile walk of transit (including bus stops), or within a block of a car share, or if required parking permits are not offered for ADUs.

Note that these may not apply in Coastal Zones, and may occasionally be modified elsewhere when necessary for safety, traffic, or infrastructure reasons. So always check with your local planning department before starting to plan any ADU project. However, these new laws now apply to most ADU projects!

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