- SB9 makes it possible for homeowners in CA to divide their property into two lots. It allows two homes to be built on each of those lots, with the effect of legalizing fourplexes in areas that previously only allowed one home. (SFR) – There is no requirement as to whether the two residential units on each lot be a “duplex,” or attached to each other, or free-standing.
- Requires the City to approve either or both:
- A housing development of no more than two units (duplex) in a single-family zone.
- Allows for a lot split to take place (a single-family lot becoming two lots).
 
- Prohibits the City from requiring more than one parking space per unit.
- The new law will mark a shift from current policies that allow only two large units — a stand-alone house and an accessory dwelling unit — on single-family lots, as well as an attached junior unit no larger than 500 square feet.
Requirements:
- The parcel is within a single-family residential zone.
- Property owners have signed an affidavit stating they will occupy 1 of the housing units as a primary residence for at least 3 years after splitting the property or the addition of units.
- Lot splits create two parcels of similar size that are at least 1200 square feet.
- Proposals must adhere to local objective zoning and design standards unless those standards would have the effect of physically precluding the construction of up to 2 units on each lot.
 unit on a property.  These ADUs or Accessory Dwelling Units are basically a 2nd dwelling on the property with a full kitchen, bathroom and bedroom, which can be rented,  leased or used for family. An ADU can be attached, detached, or even a converted garage.  They are part of the property, however, and cannot be sold separately from the primary residence.  In addition they must use existing utility connections and meters. While there cannot be more than one address on the parcel, ADUs may have a unit number or letter to differentiate the mailing address. Current regulations prohibit  local agencies from imposing an owner-occupant requirement until January 1, 2025.  Whether you love the idea or hate the idea really comes down to your situation and neighborhood.
 unit on a property.  These ADUs or Accessory Dwelling Units are basically a 2nd dwelling on the property with a full kitchen, bathroom and bedroom, which can be rented,  leased or used for family. An ADU can be attached, detached, or even a converted garage.  They are part of the property, however, and cannot be sold separately from the primary residence.  In addition they must use existing utility connections and meters. While there cannot be more than one address on the parcel, ADUs may have a unit number or letter to differentiate the mailing address. Current regulations prohibit  local agencies from imposing an owner-occupant requirement until January 1, 2025.  Whether you love the idea or hate the idea really comes down to your situation and neighborhood.