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Chico, CA 95926


Accessory Dwelling Units- New Rules and What They Mean for Homeowners


The popularity of California’s Accessory Dwelling Units (ADUs) is on the rise.  With the start of this year, several pieces of CA legislation come into effect that intend to reduce the restrictions on constructing an ADU and promote the development of ADUs on single and multi-family lots.  According to the California Department of Housing and Community Development, ADUs are an innovative, affordable, and effective option for adding much-needed housing in California.

What is an ADU and the benefits they provide

ADUs, also known as granny units and mother-in-law quarters, are additional units built on the same lot as single family residences.  These range in size from small studio type units to larger (up to 1200 sqft) multi bedroom units.  A JADU is a Junior Accessory Dwelling Unit.  JADUs are constructed within the existing home and have a separate entrance, plus access to the main unit.  JADUs typically have a small kitchenette but no bathroom facilities.

The California Department of Housing and Community Development lists the following benefits of constructing an ADU:

  • ADUs are an affordable type of home to construct in California because they do not require paying for land, major new infrastructure, structured parking, or elevators.
  • ADUs can provide a source of income for homeowners.
  • ADUs are built with cost-effective wood frame construction, which is significantly less costly than homes in new multifamily infill buildings.
  • ADUs allow extended families to be near one another while maintaining privacy.
  • ADUs can provide as much living space as many newly-built apartments and condominiums, and they’re suited well for couples, small families, friends, young people, and seniors.
  • ADUs give homeowners the flexibility to share independent living areas with family members and others, allowing seniors to age in place as they require more care.

Recent Changes to ADU Restrictions

Assembly Bill 670, Assembly Bill 881, Senate Bill 13, and Assembly Bill 68 have created major changes in the restrictions of building an ADU.  Some of the notable changes include:

  • The maximum rear and side yard setback for an ADU is 4’-0”.
  • Local jurisdictions are prohibited from requiring replacement parking if an existing garage is converted to an ADU, so long as the ADU is located within ½ mile walking distance of public transit.
  • Local jurisdictions can no longer limit the size of the ADU based on the size of the primary residence.
  • Reduced time allowed for a local agency to ministerially approve or deny the application for an ADU or junior ADU from 120 days to 60 days.
  • Local jurisdictions cannot require owner occupancy on the construction of ADUs. The primary residence and ADU can both be used as rentals.  This is in effect until January 1, 2025.
  • The governing documents of an HOA are void and unenforceable if they prohibit the construction of an ADU on a single family lot.
  • Local jurisdictions cannot impose impact fees on ADUs under 750 SQFT.
  • Allows a single family lot to contain the primary residence plus 1 ADU and 1 JADU.

Links to Bills

AB 670 (https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201920200AB670)

AB 881 (https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201920200AB881)

SB 13 (https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201920200SB13)

AB 68 (https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201920200AB68)

Considering adding an ADU to your property?

With the recent changes to the restrictions of adding an ADU and current housing shortage, you may be inspired to add an ADU and/or JADU to your property.  There are several items to consider when making this decision.

  • What are the costs associated with building an ADU? These costs include permit and school fees, design fees, utility fees, and construction fees.  Your local banker may be able to assist in financing this project.
  • How much space do you have on your property? Can a detached ADU fit, or is an attached ADU a better fit for your property?  Do you want to convert your garage to a JADU or turn your extra bedroom into a JADU?
  • Are you willing to become a landlord, regardless if you are renting the property to strangers, friends, and/or family? If so, we encourage you to speak with your local property management teams or real estate attorneys to identify the current regulations regarding becoming a landlord.

When you are ready, we are happy to assist you in navigating the planning and permitting process as well as developing your plans for construction.  Please visit our plan gallery for samples of our work.

Other Resources Available

Many local jurisdictions have ADU designs available to their residents for little to no cost.  Their plans can be found at the following links






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