SB - 9

Senate Bill 9 (SB - 9): Ability for property owners to add units for single-family zoned lots

SB 9 is intended to support increased supply of homes by encouraging building of smaller houses on existing or subdivided small lots. For SB-9 sites to be considered for the 6th Cycle Housing Element update, certain information must be gathered to demonstrate a reasonable expectation that committed units will be constructed within the eight-year cycle. SB-9 facilitates the creation of up to 4 housing units in the lot area typically used for 1 single-family home, through either adding a unit to the existing lot, or subdividing the lot to allow two units for each lot. Cities may limit the unit size to 800 square feet, but this is not required.  Only objective zoning standards, subdivision standards, and design standards can be applied. However, these standards cannot preclude the construction of two units of at least 800 square feet. 

General requirements for lot splits: 

• Each new lot must be at least 1,200 sq ft.
• Lots must be split roughly in half – smaller lots must be at least 40% of the original lots.
• A lot intended to be split cannot be created by a previous SB 9 lot split.
• New lot divisions may not be adjacent to another lot that has been split using SB 9 by the same owner, or any person acting in concert with the owner.
• Applicants must sign an affidavit stating they intend to live in one of the units for at least three years on a lot split, unless the applicant is a “community land trust” or a “qualified non-profit corporation” as defined by the Revenue and Taxation Code.