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San Diego completes ADU development pilot program

The City of San Diego has grown significantly like most cities in Southern California, but projections suggest that there is still more growth to come. To meet the growing demand for housing the City is incentivizing ADUs by reducing administrative barriers, providing pre-approved plans, and now, by initiating a pilot program to see what other improvements could be made to the process. During the most recent update of the City’s Housing Element, San Diego found that there is more than enough available inventory to meet the need for 44,880 affordable housing units by the end of this decade. This is compared to just 316 ADUs permitted and built in the decade prior. 

City of San Diego ADU Annual Construction Chart

The Housing Commission’s pilot program, which built and rented out 5 affordable ADUs, found that ADU construction in the San Diego area ranges from $116,803 for a 224-square-foot studio to $342,078 for a 1,199-square-foot three-bedroom with building times ranging from 1 to 2 years. The program found that costs for permits more than doubled with the additional bedroom (linked fees based on square footage) and most surprising they recommend hiring a professional to go through the city permit process, either through an expediter, an architect or designer, or a contractor, as the city’s permit system is geared more towards contract professionals. 

In general, square footage costs ranged from $276/square foot upwards of $521 per square foot which reflect a relatively flat site with clear right-of-way easement access as well as soils which support foundations, adequate utilities. Here’s a breakdown of the actual costs of the ADUs built as part of the pilot program.

San Diego ADU Pilot Program Costs

Other key takeaways from the pilot program include 

  • The need for a team of experienced professionals to help you through the process.
  • The need for permit-ready plans, which may still require architectural services.
  • Consider building a unit smaller than 500 square feet to benefit from fee waivers.
  • Consider the cost of splitting utilities which may add $10,000 or more to the project. By working with an experienced ADU plans expert homeowners can ensure what will be needed for utilities such as street trenching, which may add significant costs and time. 
  • The city recommends a 20% contingency reserve for construction overages.

The City has also streamlined the ADU permitting process through the passage of several bills, as highlighted in their final Housing Element report. Assembly Bills 68, 587, 671, and 881, as well as State Bill 13 simplify the ADU building process through reduced setbacks, increased maximum square footage, and reduced parking requirements and fees. 

Learn more about building an ADU in San Diego here