Senate Bill 9 (SB9) otherwise known as the “Duplex Measure” was passed by the California Assembly last week after passing in the California Senate earlier this year. The bill was signed last week by Governor Gavin Newsom.

California will now join Oregon as only the second state to effectively eliminate single family zoning. SB 9 will allow homeowners to construct up to four units on their property in two ways: conversion of a single-family home into a duplex and subdivision of the parcel into two, which would allow an additional duplex or single-family home to be built on the new parcel. If your keeping track, that is four homes where previously there was only one.

SB9 requires cities and local governments to give “ministerial,” or “by-right” approval to any requests to subdivide a lot except under very limited circumstances (historic districts, flood, and fire hazard areas). Put simply, SB 9 effectively requires automatic local government approval of these projects.

SB9 contains an owner occupancy requirement, which requires a homeowner to live in one of the units for three years from the time they get approval for a lot split. Additionally, this bill prohibits lot splits on adjacent parcels by the same individual to prevent investor/developer speculation.

According to an analysis of the bill, S.B. 9 will enable the creation of an estimated 700,000 more housing units in the state’s existing neighborhoods (California averages 100,000 new housing units each year). Housing advocates claim that by allowing homeowners to split their lots, it will expand actual homeownership instead of just rental housing.

Source: Mercury News 9/16/2021