Lot Splitting and Duplexes – SB 9 (Atkins)


John R. MacDowell, Esq., CCAL, Fiore, Racobs & Powers, A PLC


Senate Bill 9 (SB 9), signed by the Governor on September 16, provides that municipalities must allow property owners to build two dwellings on any single family lot, and to split single-family lots, subject to certain restrictions. Like the 2019 legislation allowing accessory dwelling units (ADUs), SB 9 takes land use control away from local governments.


However, the author of SB 9, Sen. Toni Atkins of San Diego, states in writing that the new law does not override a community association’s governing documents. Therefore, an association can still prohibit owners from dividing lots and building duplexes, when prohibited by the governing documents. Sen. Atkins’ letter, which is part of the legislative record, followed extensive discussions with Community Associations Institute’s California Legislative Action Committee (CAI-CLAC).


SB 9 does two things. First, it requires that municipalities approve proposals to build two residential units on one lot in urban single- family residential zones, without discretionary review, subject to some conditions (Government Code Section 65852.21). There are limits on the ability to demolish homes that have been rented or are dedicated to low-income housing, and the law does not apply to some historic properties. The law also limits the parking that can be required. However, it prohibits rentals of 30 days or less.


Second, SB 9 requires that municipalities allow owners to divide urban single-family lots into two lots of roughly equal size, but no smaller than 1,200 square feet (Government Code Section 66411.7). This lot-splitting provision also limits the ability to demolish rented or low-income properties, and does not apply to historic properties. Only limited parking may be required. An owner must sign an affidavit promising to occupy one of the lots as their primary residence for three years, and rentals of less than 30 days are prohibited.


22 January | February 2022


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