top of page
Portrait of happy two generation  family

What is the Cost to build an
Accessory Dwelling Unit?

The cost to build an ADU in San Diego varies by location, available space, personal preferences and more. 

Back in 2016, the California Legislature passed a series of laws that basically eliminated all of the red tape that prevented homeowners from building Accessory Dwelling Units (ADUs) in their backyards. Then, in 2019, the state legislature passed Assembly Bill 68 that essentially removed more of the restrictions that were involved with building ADUs. Bill 68 also included allowing ADUs to be built on multi-family properties like duplexes.

Understanding the cost to build an ADU in San Diego County

Build a Single Family Home |$637,000+

Single Family Home in San Diego.jpg

Build a Backyard ADU |$180,000+

cost to build an adu san diego.jpg

If you are thinking about building an ADU, you have no doubt learned that the median home price in San Diego

(as of 2020) is over $637,000. Many San Diego Residents are looking at their options when their family dynamics change and they need new solutions for comfortable living arrangements.  When you consider how costly it is to build a new single family home these days, the idea of building an ADU becomes much more appealing when you can do it for half the cost!

Baseline costs to build an ADU or Granny Flat


1 Bedroom ADU - $180,000

Finished 2 Bedroom ADU - $300,000


* The cost to build ADUs vary largely, depending upon personal preferences, allowable space, utilities and permits.

* Save yourself some time and money, have one of our experts evaluate your needs and give you an accurate assessment.


Licenses and Building Codes

Utility Fees and Taxes

San Diego Plan Reviews | $1490 and up

San Diego Permit Fees | $1222 and up


*when you choose the wrong builder

City-Required property upgrades

Failed Inspections

Expired Permits / New Applications

Expedited Permits

After-Hour Inspections

[Ritz ADU Design won't let this happen.]


*Inspections in San Diego county are required every 180 days until the project is finished. If one of your inspections fails, you have to apply for a new permit and pay the fees again.

[Ritz ADU Design won't let this happen.]

*San Diego County Permits all have expiration dates. If your project falls off of the timeline for any reason, you will be required to apply for another permit and pay the fees again.

[Ritz ADU Design won't let this happen.]

*Hiring multiple contractors like an architect, a designer and construction crew to build your project is the fastest way to blow your ADU construction costs off the chart. This method creates delays, mistakes, miscommunication, failed inspections and unnecessary costs.


*Ritz ADU Design Build is a One-Stop, Full Service experience. We are a complete team. A Designer, Architect and Construction crew all under one roof. We take care of EVERYTHING including obtaining permits and coordinating inspections. Our Crew has been working together for over 40 years and we are a finely tuned machine. We greatly reduce your exposure to the list of UNexpected, UNnecessary costs.

The Cost to Build an ADU
See Cost to build Adu
Couple and Builder

Can you build an ADU? Find out.

Connect with the RITZ ADU team today.

We're ready to help.

bottom of page