Thank you for joining the Planning Commission for the Accessory Dwelling Unit Study Session on October 7, 2019.
Photo by: Second Unit Center
What is an Accessory Dwelling Unit (ADU)?
ADUs (Accessory Dwelling Units), also known as granny flats or in-law units, provide independent living quarters for one household with full facilities for sleeping, eating, cooking, and sanitation on the same lot as the primary single-family dwelling. The ADU may be attached, detached, or located within the living areas of the primary dwelling unit on the lot.
Examples of ADUs include:
- Detached: The ADU structure is detached from the primary dwelling unit
- Attached: The ADU structure is attached to the primary dwelling unit
- Converted: The ADU within the existing primary dwelling unit or the ADU was established through conversion of an accessory structure (i.e. garage or pool house)
- ADUs can provide a source of income for homeowners
- ADUs give homeowners the flexibility to create a home to share with family members and others, allowing seniors to age in place as they require more care
- ADUs are a different form of housing that can help San Carlos meet its diverse housing needs
- ADUs are a critical form of infill-development that can be affordable and offer additional housing opportunities within existing neighborhoods
- ADUs are an affordable type of home to construct because they do not require paying for land, major new infrastructure, structured parking, or elevators.
Reason for the ADU Update:
In response to the Bay Area’s regional housing shortages, Governor Brown signed new laws (SB 1069 and AB 2299) from 2016 to 2018 to encourage the construction of more ADUs by reducing the regulatory barriers commonly found in local zoning ordinances. To comply with the updated state policies, the City of San Carlos is undergoing a process of updating its local ADU Ordinance (currently titled Second Dwelling Unit in the City’s municipal code).
Study Session Details:
Many members of the community attended in response to extensive outreach. Staff updated the Commission on recent laws that will be going into effect as of January 1, 2020. In addition, staff presented recommendations on specific ADU policies. The Commission directed staff to work on the following items:
1) Create specific definitions and building code language for kitchens, bathrooms, and cooking facilities.
2) Prepare exhibits showing the possibilities of maximum single-family floor area with ADUs.
3) Draft a summary of existing vs. new parking requirements.
4) List the impacts of state law on properties within the Hillside Overlay District and adjacent to creeks.
5) Provide information on possible incentives (other than an increase in floor area) to encourage affordable units.
6) Meet with the Transportation and Circulation Commission for feedback.
7) Determine if Junior ADUs have to be allowed in San Carlos.
Community Development staff is currently working on these items and will return to the Planning Commission with a draft ordinance within the next few months, which will be forwarded to the City Council for consideration in Winter/Spring 2020.
Summary of New State Requirements:
- Additional parking for the ADU is not required at all if the ADU:
- Is within a half mile from public transit.
- Is within an architecturally and historically significant historic district.
- Is part of an existing primary residence or an existing accessory structure.
- Is in an area where on-street parking permits are required, but not offered to the occupant of the ADU.
- Is located within one block of a car share area.
- If none of the 5 criteria above are met, and the City elects to require parking for the ADU, then a maximum of one parking space per ADU can be required per State law.
- An ADU parking space may be in a tandem configuration and/or located in setback areas on the same lot
ADUs shall not be considered new residential uses for the purpose of calculating utility connection fees or capacity charges, including water and sewer service
Fire sprinklers shall not be required in an accessory unit if they are not required in the primary residence.
- Local government must ministerially approve an application to create within a single family residential zone one ADU per single family lot if the unit is:
- contained within an existing residence or accessory structure.
- has independent exterior access from the existing residence.
- has side and rear setbacks that are sufficient for fire safety.
- These provisions apply within all single-family residential zones and ADUs within existing space must be allowed in all of these zones. No additional parking or other development standards can be applied except for building code requirements.
Local government must ministerially approve ADUs if the unit complies with certain parking requirements, the maximum allowable size of an attached ADU, and setback requirements, as follows:
- The unit is not intended for sale separate from the primary residence and may be rented.
- The lot is zoned for single-family or multifamily use and contains an existing, single-family dwelling.
- The unit is either attached to an existing dwelling or located within the living area of the existing dwelling or detached and on the same lot.
- The increased floor area of the unit does not exceed 50% of the existing living area, with a maximum increase in floor area of 1,200 square feet.
- The total area of floor space for a detached accessory dwelling unit does not exceed 1,200 square feet.
- No passageway can be required.
- No setback can be required from an existing garage that is converted to an ADU.
- Compliance with local building code requirements.
- Approval by the local health officer where private sewage disposal system is being used.
As of January 1, 2019, homeowners who created ADUs without the required building permits have the opportunity to bring their ADUs into compliance. For ADUs that were constructed without building permits, local building officials can determine the date of construction of the ADU, apply the building standards in effect at that date of construction, and issue a retroactive building permit.