Community Planners Committee Recommends Changes to San Diego’s ‘Bonus ADU Program’

The Community Planners Committee (CPC) is an officially-recognized body of leaders from all of San Diego’s official community planning boards. It now has jumped into the fray of reforming the city’s Bonus ADU Program with the following recommendations expressed in this letter addressed to the San Diego City Council, dated April 24, 2025, and signed by Andrea Schlegeter, chair of the CPC.

To San Diego City Council

When setting out to provide recommendations for changes to the Bonus Accessory Dwelling Unit (ADU) Program the Community Planners Committee (CPC) followed three guiding principals: adhere to state law, treat all development applicants equally, and find a way to address the lag in affordable housing at the lower end of the Area Median Income (AMI) scale.

To follow the first guiding principal, the City and the State should be held at their word and to the reasoning for increased density. SB 9 is the overriding state legislation for single family lots (RS zone), which allows for lots to be split. Pairing this with the state ADU regulations every RS zoned lot can have a primary residence, an ADU, a Junior ADU (JADU), and a bonus ADU.

Thus the CPC has come up with a “4 means 4” proposal. This is the simplest way of adhering to state law, while clarifying what the max density in RS zones is.

There are many good arguments in favor of capping density in RS zones at four.

• At the City level, four is the dividing line between having trash services provided or having the option to contract out.
• At the federal level, four is the dividing line HUD uses to qualify a property as single family or multi family.
• Financing regulations change when you go from four housing units to five housing units.

With “4 means 4” as our starting point, the CPC recommends allowing for one bonus ADU in any and all RS zones. The CPC also recommends that this bonus ADU be deeded affordable.
Considering every Councilmember agrees the City is in a housing crisis, particularly a low income and missing middle housing crisis, more needs to be done to fill this gap.
According to the San Diego Housing Commission, there is a deficit of around 92,000 housing units for very low and extremely low (<50% AMI and <30% AMI respectively) income residents, while there is a surplus of housing units for low income and moderate income (<80% AMI and <120% AMI respectively). To fix this, the affordability tier assigned to the bonus ADU should be tied to the CTAC zone rating. Meaning that areas that are the highest resourced should have the most affordable units (<30% AMI) while the lowest resourced areas should have their bonus ADU affordability set at 80-120% AMI. This will stop the packing of neighborhoods with one type of housing, and to a degree address the under building of low income affordable units.

Additionally, it is concerning that the deed restrictions on Bonus ADUs are not the same as other deed restricted housing. To treat all development applicants equally, and simplify the code the deed restrictions on ADUs should be brought in line with the rest of the City deed restrictions, which is 55 years.

Since the City’s Bonus ADU program has been passed, the state has increased the number of allowable ADUs in multi family zones (RM Zones). As of now, you can build one market rate ADU for every dwelling unit on the lot up to eight (8) ADUs. If you only have one dwelling unit on the lot you are still allowed your two (2) ADUs. Therefore the city has room to scale back the Bonus ADU program in RM zones.

The CPC intention is to to keep this proposal simple: two (2) affordable Bonus ADUs are allowed on any RM lots. Additionally, the CPC believes the same affordability standards be applied to the RM zones that we are requesting in the RS zones, i.e. the most affordable units go into the highest resourced areas.

Finally, we have four recommendations that should apply across both the RS and RM Bonus ADU programs.

First, state law strictly forbids ADUs from being rented for less than 31 days, but it is a gaping loophole to allow someone to build an ADU move into that and rent their primary residence out on STR platforms. This loophole needs to be closed for the good of San Diego’s housing supply. The CPC recommends that any dwelling unit on a lot that has built bonus or state ADUs have >31 day rental restrictions placed on it.

Second, to ensure residents are not parking over a quarter mile away from their homes, one parking space per ADU should be required outside of a Transit Priority Area (TPA). As we know, TPAs do not always have an active high quality public transportation route, they can just have a planned route. Under the current ordinance, affordable ADUs would become market rate ADUs before those transportation routes will be provided. In the meantime it is necessary to maintain an off-street parking stock. Any development inside a TPA will still have no parking requirements.

Third, the CPC requests that setbacks and height limits be reverted to the state standard. One of the biggest complaints from neighbors is the zero setback and towering ADUs being built adjacent to their back yards, taking away any privacy. This will also help ensure a new development blends into the neighborhoods which will lead to less complaints about ADUs.

Fourth, to addresses safety concerns around evacuations the Bonus ADU program should not apply in Very High Fire Hazard Severity zones or streets where there is a single egress (e.g. cul-de-sacs).

The members of the CPC are looking forward to the robust debate that will come with the public discussions starting with the Planning Commission on May 1st. We will see you there!

Sincerely,

Andrea Schlageter
Chair, Community Planners Committee.