3 Times San Diego's DSD Overcharged Me $10,000+ for ADU Permits

By Sean Canning

When it comes to permitting in San Diego the struggle is real!  If you’re considering an Accessory Dwelling Unit project like a Companion Unit or a Junior Unit chances are your budget is tight. A simple misunderstanding of the code can make your project subject to exorbitant City fees, which on these smaller projects can be a large percentage of the total project cost.  

Ten Seventy Architecture is a San Diego based studio focusing on modern design.  We’re experts in designing + permitting projects in San Diego with 10 years of experience. One of our staff members was previously an employee of San Diego’s Development Services Department (DSD) for 5 years.  If we can’t pull a permit here, no one can!  

But every time we submit a project for a permit, large or small, we’re met with a gauntlet of obstacles - gross misinterpretation of the DSD staff’s own municipal code.  If the staff doesn’t understand their own code, a mistake can result in a huge + unexpected cost to you.  

Just in the past couple months we’ve argued as advocates for our clients, eliminating giant fees which were applied by the DSD staff in error.  This is a story about our most recent 3 projects + how we saved our clients thousands of dollars.  

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On a recent project in Logan Heights, we proposed to add 2 Companion Unit ADUs behind an existing single family home. This is permitted by the new California State ADU regulations, in place since January 2020, which allow for multiple ADUs on lots. Companion Units have impact fees waived, are charged 50% the sewer/water fees Dwelling Units are subject to, do not require fire sprinklers (if there is an existing home without fire sprinklers), + can encroach into side or rear setbacks.  

When our plan review came back, the DSD determined that both of our proposed Companion Units would have to be designated as Dwelling Units proper. Imagine our shock!  This would make these units subject to the above mentioned fees + in addition both units would have to be redesigned / engineered to be within the setbacks.  

$1,127  transportation fees

$13,918  impact fees

$7,171  added sewer/water fees

$2,500  fire sprinkler engineering + install cost

$2,500  redesign / engineering cost


On another project, we proposed a Companion Unit ADU over a 4-car garage to be constructed behind an existing single family dwelling unit in a multi-family zone.  The zone would allows for a maximum of 2 Dwelling Units + ADUs.  Strategically, we recommended our client build an ADU to avoid the incredible fees associated with new Dwelling Units.  They agreed so we designed according to this strategy, within our clients tight budget.  

When we received our plan check from the DSD’s Zoning Department they incorrectly stated that we could not construct an Accessory Dwelling Unit until we had maxed out the Dwelling Units.  Basically forcing us to switch the proposed ADU to a Dwelling Unit, which would’ve cost our client a significant amount of their project budget.  

$747  transportation fees              

$7,101  impact fees        

$3,585.50  added sewer/water fees    

$2,500  fire sprinkler engineering + install cost


On a separate project the DSD plan checker incorrectly included our Accessory Dwelling Unit in the projects valuation calculation, which was above the $100,000 threshold.  This triggers public improvements like a driveway + curb cut upgrade (which was not part of our planned scope of work).  In addition to the added labor, a Right Of Way permit would have to be obtained, costing our client more money + further delaying the construction of their project.  

The problem is, Accessory Structures are exempt from this valuation calculation per SDMC 142.0611(b) which clearly states ‘The construction of accessory structures are exempt’.  City staff insisted that Accessory Dwelling Units are not considered Accessory Structures.  This blew my mind, but evidently we study the code more than they do.  The Municipal Code defines Companion Units as ‘an accessory structure on a residential lot that provides independent living facilities for one or more persons..’  After discussing this with a supervisor, the DSD conceded to eliminating the incorrect valuation + the work in the right of way.  

$1,500  ROW engineering

$624.89  ROW permit

$450  general plan maintenance

$818  Inspection

$7,500  driveway work


2020 has been a year full of epic disasters.  San Diego’s Development Services Department has been following suit, starting with an unprecedented asbestos scandal to the rushed unrolling of their digital submittal process (yes it took the DSD until 2020 to learn how to open as PDF).  

We’ve learned that the DSD has not done their homework on the State’s new ADU regulations + the customers are the ones who are paying the price -literally.  It’s important to be familiar + up to date on the codes / fees which apply to your project, especially on the small Companion Unit + Junior Unit projects.  The true intent of these ADUs is to provide a lower cost of entry to acomodate our housing crisis, but if you zig where you should’ve zagged your fees can easily jump $10,000.  On these smaller projects that can be a large percentage of the total construction cost, making the project financially out of reach.  

We’ll reserve judgment as to whether these incorrect fees are the result of negligence or incompetence.  The important takeaway here is that despite DSD staff insisting they were correct, we were able to cite code sections which proved them wrong.  All three of these projects were initially overcharged, but we successfully argued for the fees to be corrected.  Study the code!  

Click here to download a free copy of our


If you need help with understanding the new California State Accessory Dwelling Unit regulations, the San Diego Municipal Code, or have a project you'd like to discuss, feel free to reach out.  We're here to help.  

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