Advocacy Updates, AIACA|

SB 9 and SB 10 have been signed into law by Governor Newsom.

SB 9 has a direct impact on additional dwelling units (ADU) production of which the architect should be aware.  Property owners will now be faced with a primary decision: ADU or SB 9.

The final version of SB 9 does NOT allow splitting a residential lot AND for having an ADU on each lot.  Instead, SB 9 has an EITHER-OR provision.  A property owner can EITHER add an ADU for 2 units (ADU and JADU for 3 units), OR with SB 9 split the property resulting in 2 units that are not allowed an ADU or JADU.  The result is EITHER 2-3 units / OR 2 units total, NOT 6.

Most urban residential properties are too small for an SB 9 lot split, or are better suited for an ADU/JADU.  Approval for these is entirely ministerial allowing 4’ side and rear setbacks, a maximized floor area, height limited to one story at 19’, with no parking required, and more importantly, impact fees for 749 SF units are waived, and utility services feed off the main house, etc.  This makes for a variety of housing options in a range of low-end costs.

SB 9 lot splits are also ministerial, which could simply be approved with a single sheet plot plan, or with more details if required.  After that, the building design and construction is as for any undeveloped property.  As per SB 9, the lot must be able to accommodate at least an 800 SF unit and one parking space, and there is no setback required along the new internally created property line — meaning that the new house can be set against an existing building wall in a classic duplex fashion.  The new house otherwise needs to conform all other requirements including zoning, setbacks and height, and is subject to all planning and design review requirements, development fees, school and road charges, sprinklers, and all new utilities with buy-in and connection fees, etc.  These costs can be quite high, but they are not added into a Prop 13 protected assessment until the property is sold at market rate.

Lot splits were the classic way to make money, that was, until zoning, the subdivision act, EIRs, and public planning review arrived in California.  A property owner could simply parcel off a piece land and sell it.  SB 9 restores some of these original land rights.  The new lot could be held, developed, sold as-is, or sold with approved plans and shovel-ready.  The property could also be deed restricted to control its impact on the existing home.

Choosing either ADU or SB 9 leads to two very distinct paths, each with many considerations yet to be explored in comparison.  Architects are uniquely qualified to implement SB 9 for successful and satisfying results.  There is a varied set of options under SB 9 to consider for the optimum outcome, not just for our clients, but for our communities.

SB 10 allows a city or county to pass an ordinance to zone any parcel for up to 10 units of residential density, at a height specified by the local government in the ordinance, if the parcel is located in a transit-rich area or an urban infill site.

SB 10 is intended to allow greater density in housing construction due to the high cost of land in California.  The hope is greater density will make it easier to develop housing affordable to lower-income households

SB 9 can be viewed here.

SB 10 can be viewed here.


AIA California
AIA California
Celebrating over 75 years of service, the AIA California actively promotes the value of design and advocates for the architectural profession. AIA CA is an association of 11,000 dedicated and passionate members who share a commitment to design excellence and livability in California’s natural and built environments.

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