Will SB9 & SB10 Change the Landscape of San Carlos?

September 22, 2021


Lots of Questions, But Few Answers…For Now.

Homeowners in San Carlos and in every community across California received the shock of their home ownership lives last week when it was announced that bills SB9 & SB10 were signed into law, literally hours after the conclusion of the gubernatorial recall election. For those of you not familiar with these two bills, they essentially eliminate single-family zoning restrictions in most neighborhoods across the state in an effort to ease the housing crisis. This opens the door to multi-family dwellings being built in residential neighborhoods, and for small apartment complexes to be built in neighborhoods near public transit hubs. There's a good article that was published in the San Jose Mercury that talks about the high-level points of both laws. You can read that article here.

SB9 will likely impact far more homeowners, as it allows property owners to split single lots into two separate lots and then place duplexes on each — thus converting what was a single family home into 4 distinct living units. In a community like San Carlos where the density of homes in the older neighborhoods is already a hot button because of all the new development taking place, this may rapidly become a very contentious issue.

The sister bill to this, SB10, will allow developers to build complexes up to 10 units in residential neighborhoods that are close to transit centers.

The key thing to remember with both of these bills is that cities will be required to approve any project that meets “specified size and design standards”. In other words, municipalities like San Carlos will likely be powerless to block any development that adheres to the aforementioned standards — very much like the current state law that allows auxiliary dwelling units (ADUs) to be built on any residential property provided similar guidelines are met. Local municipalities have very little veto power over ADUs, and this appears to be the same level of power-grab by the State of California.

I have received quite a few calls and emails from concerned homeowners about this recent development, and I've asked the folks at the City of San Carlos for some additional details about these “specified size and design standards”, and just how these new laws may impact San Carlos residents. Like virtually every other state bill, this one seems long on ideas and short on details, so the City needs to dig in and digest just what it really means. They plan to have an official response out to the public in the coming weeks, so stay tuned to the blog for updates as they become available.

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  1. Kelly on September 22, 2021 at 7:31 pm

    I believe there are stats that suggest less than 5% of developed areas could really support these new dwellings, so the ability to abuse or fundamentally change the character of a neighborhood seems negligible. In Belmont the ADU changes also have very little impact on how many ADUs actually get built. Often much hand wringing over nothing. The intent here seems good for all.

  2. Chuck Gillooley on September 22, 2021 at 8:31 pm

    Thank you for weighing in. I have seen similar predictions that the number of lots that can be split for this purpose will still be a small number, but I will still wait to see what guidelines the City ultimately will adhere to. Regarding ADUs, I’m seeing the pace of ADU construction actually picking up — at least in San Carlos. There’s one cul-de-sac where there are two units being built right now, and the interest level still seems very high with prospective home buyers.

  3. Bruce Cumming on September 23, 2021 at 7:36 pm

    Hi Chuck and Kelly, You both mention that you believe these laws will only affect a small amount of properties perhaps as little as 5%. What do you base that conclusion on? I have seen information that these would apply to lots as small as 2400 sq. feet. Am I incorrect? I live in the White Oaks on a 5600 square. ft. lot that might be subject to demolition & construction of two replacement homes. By the way this scenario would do little to solve the affordable housing crisis . If my home was sold for $2. 3 million, torn down and two homes built, they would sell for at least $3 million each and would be unaffordable to most people. This is bad law imposed by the State as you said Chuck “long on ideas short on details”.

  4. Chuck Gillooley on September 23, 2021 at 8:30 pm

    Hi Bruce,

    Thanks for your comment. Just to clarify my stance on these bills, I just acknowledged that I read somewhere someone’s opinion that the impact may not be that significant. I certainly have no details that would add credibility to that article’s stance, since it seems nobody (including the City of San Carlos) really knows the potential impact of this bill. I absolutely do believe, however, that it would significantly degrade the quality of life in White Oaks if all of a sudden a bunch of lots were being split and duplexes being erected. I’m looking forward to the response from the City of San Carlos so that we’ll all be on the same page.



  5. Bruce Salazar on November 26, 2021 at 12:40 pm

    This was put in place by Newsom to cater to special interests developers. I do not remember one neighbor ever saying they wish they could build a 4 plex on their lot. Lets not put our heads in the sand and pretend anything different. No regard given to infrastructure of schools, police, fire, hospitals. Single family neighborhoods were designed to support single family living. Special interest is controlling our government by lobbying $ . We had are chance to get rid of Newsome and blew it. Bruce is spot on with running the numbers. This will not create affordable housing. For Newsome to sign a law that has no regard for the majority of Californians shows exactly why we should have remived the career politician out. I dont think it will happen overnight but I sure dont want to be the first house next to the 5000 sq fort lot that sub divide into 2 lots and builds a duplex on each lot with no plan for parking or any other overfliw situation this will cause. Californians need to fight back.

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