How to create a duplex or subdivision under the provisions of Senate Bill 9 (SB 9)

At CityStructure, our vision is a world where every homeowner has a clear understanding of the development potential of their property. This is why we give you free access to the Untapped Development Potential for any property.

Under Senate Bill 9 (SB 9) passed in 2021, you may construct up to two units on a property zoned for single-family residential, and under the City's Ordinance 30706 passed in December 2021 and as allowed by SB 9, the zoning district must be R-1 or PD and the two units must be a duplex.

More specifically:

  • You may create a duplex by remodeling the existing house or adding on to it;
  • You may demolish an existing house and build a new duplex; or
  • You may build a new duplex on a vacant lot that is zoned single-family residential (R-1 or PD zones).
  • Existing structures on a lot are not a constraint if those structures could be converted or demolished to make room for the new units.

Owner Occupancy. Under SB 9, the applicant for a subdivision must commit to occupying one lot as their primary residence for a minimum of three years from the date of approval of the subdivision. To ensure compliance with this requirement, a dwelling unit must exist on the property at time of approval of the subdivision.

Subdividing Adjoining Properties is Prohibited. SB 9 prohibits an applicant, or applicants working in concert, from subdividing adjoining lots using the provisions of SB 9.

Lot Size. Either lot resulting from the subdivision cannot be less than 40 percent of the original lot size (before subdivision) and/or less than 1,200 square feet in size.

Protected Units. Does the property contain a residential unit or units where any of the following apply?

  • Unit/s are subject to the City’s Rent Control Ordinance.
  • The Ellis Act Ordinance has been exercised to remove the unit/s from the rental market within the last 15 years.
  • The unit/s have been occupied by a tenant in the last three years.

If yes to any of the above, the subdivision and future buildings cannot alter or demolish the unit/s.

As exciting as it sounds, getting your permits fast by using the streamlined permitting process, could be tricky because the eligibility conditions have to follow strict rules. We put together a quick quiz to make it easy for you to check eligibility.