Building an Urban Infill Unit SB 9
SB 9 (The California HOME Act) was signed by Governor Newsom on September 16, 2021, and became effective January 1, 2022. SB 9 grants approval of: (1) a one-time, two-lot subdivision and subsequent development of up two units per resulting lot; or (2) development of up to four units on a lot that is not subdivided without any public hearing or discretionary (subjective) review.
Background and Adoption of the Urban Infill Unit Ordinance
On January 10, 2022, the San Carlos City Council adopted an Urgency Ordinance to impose interim regulations and objective standards for the subdivision and development of qualified Senate Bill (SB) 9 properties, or as the City refers to as Urban Infill Units. On February 14, 2022, City Council approved the extension of the SB 9 Urgency Ordinance 1576 for a period of 10 months and 15 days.
On November 13, 2023, the San Carlos City Council adopted the permanent SB-9 Ordinance 1603 which became effective on December 13, 2023. At this time the City’s previous Urgency Ordinance expired. Formally referred to as SB 9 units, the City now refers to these units as Urban Infill Units. The new Urban Infill Unit regulations has been incorporated into the San Carlos Municipal Code (see SCMC Section 18.23.310).
For meeting information, agenda and staff reports visit the Public Meetings page.
Review and Permitting Process
An application for an Urban Infill Unit will need to be submitted to the Planning Division for review. Approval of the planning application is required before the building permit submission with applicable fees. No public hearing or discretionary review is required for urban infill projects. The length of the review process varies depending on the scope of the project and the completeness of the submission. Each round of review can take up to 30 days and a few rounds of review are common. To help expedite the process, the City highly encourages a re-application meeting with a planner. Once a formal application is submitted, applications will be assigned a planner who will notify applicants of the status of their application.
Background and Adoption of the Urban Infill Unit Ordinance
On January 10, 2022, the San Carlos City Council adopted an Urgency Ordinance to impose interim regulations and objective standards for the subdivision and development of qualified Senate Bill (SB) 9 properties, or as the City refers to as Urban Infill Units. On February 14, 2022, City Council approved the extension of the SB 9 Urgency Ordinance 1576 for a period of 10 months and 15 days.
On November 13, 2023, the San Carlos City Council adopted the permanent SB-9 Ordinance 1603 which became effective on December 13, 2023. At this time the City’s previous Urgency Ordinance expired. Formally referred to as SB 9 units, the City now refers to these units as Urban Infill Units. The new Urban Infill Unit regulations has been incorporated into the San Carlos Municipal Code (see SCMC Section 18.23.310).
For meeting information, agenda and staff reports visit the Public Meetings page.
Review and Permitting Process
An application for an Urban Infill Unit will need to be submitted to the Planning Division for review. Approval of the planning application is required before the building permit submission with applicable fees. No public hearing or discretionary review is required for urban infill projects. The length of the review process varies depending on the scope of the project and the completeness of the submission. Each round of review can take up to 30 days and a few rounds of review are common. To help expedite the process, the City highly encourages a re-application meeting with a planner. Once a formal application is submitted, applications will be assigned a planner who will notify applicants of the status of their application.
Eligibility Requirements for Urban Infill Units
- Project site must be zoned in RS-3 or RS-6 (Single-Family Districts). To check a property’s zoning, click here.
- Project site was not previously subdivided under SB 9.
- Project site is not locatedwithin a historic district or included on the State Historic Resources Inventory.
- Project site is not subject to a recorded covenant that restricts rents to levels affordable to persons and families of moderate, low, or very low income.
- Project site would not require demolition or alteration of any housing that has been occupied by a rental tenant at any time in the last 3 years.
- Project site is not located in an earthquake fault zone, lands under conservation easement, a federally designated flood plain, and high fire severity zones as defined under State Law.
General Development Requirements
- If subdividing, property owners must sign a property affidavit statingthey will live in one of the units for at least 3 years.
- Subdivision cannotcreate a flag lot.
- Parcels subdivided must be a minimum of 1,200 square ft in size.
- It cannotbe smaller than 40% of the lot area of the original parcel.
- Projects should meet the objective design standards for urban infill units per SCMC 18.23.310-(C)(3).
- The combined floor area for all units depends on the underlying zoning district.
- Maximum height for Urban Infill Units
- 16 ft (attached or detached)
- 20 ft for projects in hillside overlay districts
- Setbacks shall adhere to the underlying zoning district. No setback is required for units constructed in the same location as an existing structure on the parcel.
- Parking Requirements
- One uncovered parking space (10 ft wide by 20 ft in depth) is required per urban infill unit.
- No parking is required if within ½ mile of walking distance to a high-quality transit corridor, major transit stop, or if there is a car share vehicle located within one block of the parcel.
Frequently Asked Questions
- You are allowed to build up to four units. Parcels created using SB 9 will have no more than two units each. Units can consist of a primary dwelling unit, a duplex, urban infill units, an ADU, or JADU.
- Depending on the scope of work, the maximum allowable floor area depends on the size of the parcel and the underlying zoning districts.
- Parcels created from an urban lot split must be a minimum of 1,200 square feet in lot size. Lots, at minimum, must be split at least 40% of the original lot size (40-60 split). In addition, subdivided parcels can not create a flag lot.
- Yes, but units cannot be short-term rentals (less than 30 days). In addition, if the project proposes a lot split, the property owner must sign a property affidavit stating they will live in one of the units for a minimum of 3 years before renting or selling the units. If the project proposes multiple units with no lot split, the units cannot be sold separately.
- No, since urban infill units are approved ministerially, they are statutorily exempt from the California Environmental Quality Act (CEQA).