SB9:
Two Unit Development & Urban Lot Split
Senate Bill 9, commonly referred to as SB 9, is a California statute enabling the addition of extra dwelling units to certain Single Family Lots on an existing parcel. The legislation introduces two specific development standards, namely the Two Unit Development and Urban Lot Split, designed to streamline and support this process. This concise guide aims to assist you in determining whether leveraging the development tools provided by SB 9 aligns with the needs of your property.
For further inquiries or additional information, feel free to contact us here or send an email to info@vennstudiola.com.
What is SB 9?
SB 9 was enacted into California law in 2021 and formally put into effect in 2022. Historically, owners of Single Family Lots were restricted to a single dwelling unit along with an ADU and JADU per parcel. However, recognizing the escalating demand for housing in California, SB 9 confronts this challenge directly by introducing two innovative development standards: Two Unit Development and Urban Lot Split
Under SB 9, Two Unit Development allows for the establishment of up to 2 main dwelling units on a Single Family Lot. The standard mandates that each main dwelling unit must have a minimum area of 800 square feet, in addition to any ADUs and JADUs permitted by California law. The floor area of these units may vary depending on lot size and local zoning regulations.
An Urban Lot Split involves dividing a Single Family Lot into two lots, each measuring at least 1,200 square feet. Each new lot is granted permission for up to 2 dwelling units, whether attached or detached, with a minimum size requirement of 800 square feet per unit.
In both scenarios, SB 9 permits a total of 4 units on a Single Family Lot. Employing the Two Unit Development and Urban Lot Split approach provides an effective means to enhance housing density on an existing parcel, enabling property owners to expand the livable space on their property.
Venn Studio has worked on a wide variety of project types in Los Angeles County. Each Jurisdiction has its own rules and regulations regarding the enforcement of SB 9. To aid in navigating this process, we have compiled a concise list of questions and answers addressing SB 9 rules and procedures.
Which Lots Qualify for SB 9?
In brief, in order for a Single Family Lot to qualify for SB 9, it must be located in what the US Census considers an Urbanized area.Other factors may render some lots ineligible.
These factors encompass, but are not restricted to, being situated in a liquefaction zone, historic zone, or affordable housing restriction zone, having a tenant residing on the lot for the past three years, or having undergone previous subdivision.
SB 9 eligibility may also be denied if the proposed development is proven to be detrimental to public health and safety or demonstrated to adversely affect the surrounding neighborhood.
What Can I Put on My Lot According to SB 9?
Within the framework of SB 9, homeowners have the flexibility to choose between Two Unit Development, Urban Lot Split, or a blend of both options.
Regardless of the chosen standard, a Single Family Lot is permitted a total of 4 units under SB 9.
Two Unit Development
The Two Unit Development facet permits the construction of up to two main dwelling units alongside ADUs and JADUs on a Single Family Lot. Each main dwelling unit is required to have a minimum area of 800 square feet, with the possibility of exceeding this size based on local zoning regulations.
Urban Lot Split
Alternatively, Urban Lot Split development enables the division of a Single Family Lot into two parcels, each with a minimum area of 1,200 square feet, following a 50/50 or 40/60 split. When combined with Two Unit Development, each resulting lot must accommodate the construction of two dwellings.
What are Some Other SB 9 Standards?
There are varying degrees in how various jurisdictions will enforce SB 9. However, here are a few standards that must be enforced across all jurisdictions.
Number of Dwelling Units
Under SB 9 the Two unit development and Urban Lot Split will allow you to build up to 4 units max per lot, I.E.; two main dwelling units, an ADU, and JADU.
Residential Floor Area
According to SB 9, there can be no rules that prevent each dwelling unit from having a minimum area of at least 800 square feet. If the lot has enough space, the units may be larger if allowed by the local zoning regulations.
Setbacks
Each new unit developed under SB 9 must have a minimum of a 4 foot side and rear yard setbacks. There are no setbacks for existing structures or a replacement structure built in the same place with the same footprint. Front yard setbacks and plane break requirements will still apply, if applicable.
Parking
No new parking is required for a new dwelling unit if a parcel is located within ½ mile of transit or within 1 block of a car share vehicle.
Attached/Detached Units
Attached or detached units are permitted on each lot under SB 9, however it is important to check local rules and regulations regarding fire separations.
When Renting
SB 9 is intended to address the lack of long term housing in the state of California. Therefore, units set up for rent on lots using SB 9 standards cannot be rented out for less than 30 days.
ADUs & JADUs
In accordance with SB 9, the inclusion of ADUs and JADUs is contingent upon each lot accommodating no more than 2 main dwelling units.
For instance, if a lot adopts the Two Unit Development standard under SB 9, permitting up to two main dwelling units along with an ADU and JADU may be allowed. In cases where a Duplex is proposed, utilizing the Two Unit Development standard permits up to two ADUs for the parcel, subject to certain restrictions.
Alternatively, if a lot adheres to the Urban Lot Split Standard, each resulting lot is permitted one dwelling unit, along with an ADU and JADU per lot, respectively, while precluding any additional units on each lot.
For more detailed information, refer to our ADU & JADU Journal.
Lot Splitting
Under the Urban Lot Split development standard, parcels can be split 50/50 or 40/60, with no lot being smaller than 1,200 square feet.
An applicant may only apply for the Urban Lot Split after having lived on the property for a minimum of 3 years and having proof that it has been the applicant’s primary residence in that time.
Additionally, a lot becomes ineligible for an Urban Lot Split if it has been previously split, or if the owner has adjacent properties or has any association with parties that have previously split the adjacent lot.
Possible Combinations
Need more information on what building combination can apply to your Single Family Lot? Have questions? Contact us here or send us an email at info@vennstudiola.com
What is the SB 9 Permit Process Like?
Each city within the county has its own set of rules governing the SB 9 process. Venn Studio has experience in permitting residential developments in many of the local jurisdictions.
Send us an email with your address and we can let you know what type of configuration would work best for your lot - info@vennstudiola.com
How much will an SB 9 Development Cost?
We work with expert local contractors who cater to a variety of price points. These contractors understand the importance of budget and timeline, and we like to work closely with them to design units that fit your budget.
How long does it take to build an SB 9 Development?
When working with the right contractors, a dwelling unit can take 6-10 months to complete depending on the size, complexity and site conditions. In our experience, we have worked with expert local contractors to help limit the disruption to your daily life. Construction can happen in your backyard while you continue to live in your house.
Are you ready for SB 9?
Contact us here, or send us an email to start the conversation. We'll help you determine which SB 9 configuration, size and type is best for you!