ADU Permit Cost in San Diego

Key Takeaways / TLDR

Building permits are required for any new build or major renovation in San Diego.

San Diego homeowners looking to build an accessory dwelling unit or ADU alongside their primary residence can expect to pay between $9,000 and $20,000 for a building permit. The exact cost for your ADU building permit depends on whether you’re building a smaller unit or a larger one, and if you’re taking on new construction or converting an existing structure (like a garage).

As for what to expect from the permitting process, recent California laws dictate that all building permit applications must either be approved or denied within 60 days of application. If your building permit is denied, you can make modifications to your building plans and application and resubmit, at which point the clock starts again.

How Much Does an ADU Permit Cost in San Diego?

The typical ADU permit in San Diego costs between $9,000 and $20,000. Where your ADU project falls within this range depends on factors including:

• The Type of ADU: New, detached ADUs have higher permit costs than those that are being built out of an existing structure, like a garage, or being built within the footprint of the existing home, like in a basement or attic. (ADUs that are built within the existing footprint of the home are actually what are known as JADUs, or junior accessory dwelling units.)
• Project Size and Scope: Larger ADUs can incur more significant construction costs, and the permit costs are no exception. The larger and more complex your design, the more you can expect to pay in permitting fees. This is because smaller units (under 750 square feet) are typically exempt from certain fees, including impact fees and school fees.
• Location: Along with cost variances between states, the zoning laws in particular neighborhoods, like coastal zones, might have higher fees for ADUs seeking a permit. To see if your neighborhood has any additional costs associated with permitting, contact your local building department.

Strategic planning and understanding of permit costs are vital in densely populated areas to maximize space and comply with local zoning regulations efficiently.

City of San Diego ADU Permit Fees

A permit fee isn’t a single fee but rather a sum of various fees. Here are all the fees included in the permit fee. Note that these are the fees for the City of San Diego and unincorporated cities in San Diego County, and they may differ slightly from those in surrounding cities.

Check out the table below to see a breakdown of the costs for City of San Diego ADU permit fees.

The best way to get an accurate estimate for the permitting fees in your city is to contact your local building department or to reach out to an experienced ADU builder.

Understanding ADU Fees Waived with SB13

In recent years, California lawmakers have passed a series of laws that have made building ADUs easier for homeowners to encourage more ADU construction in an effort to solve the state’s housing shortage and provide more affordable housing options.

One of these laws is SB13, which waives certain fees associated with permitting for attached or detached units under 750 square feet. These include development impact fees, school fees, and park fees.

Junior ADUs or JADUs that are built within the footprint of your existing home are also eligible for these fee waivers, as JADUs must be 500 square feet or under. There are also additional fee waivers associated with this kind of build. JADUs can’t be charged utility connection fees, for example, since they tap into the existing home’s electrical.

If you’re building an additional living space that’s larger than 750 square feet, SB13 does offer reduced fees to ensure they aren’t too burdensome on homeowners. Typically, these fees are determined proportionally by comparing the size of your proposed ADU with the size of your primary dwelling unit.

Stay informed about California’s SB13, which can significantly reduce ADU development fees through various waivers, benefiting homeowners financially.

Is there an ADU Permit Fee Waiver in San Diego?

Along with statewide fee waivers, the City of San Diego had a fee waiver program that exempted ADUs from paying plan check fees, traffic impact fees, inspection fees, and drainage/sewer fees. Oftentimes, these were significant, saving homeowners as much as $10,000 or even $15,000 in construction costs. Unfortunately, this was a trial program and ended in 2024. Though some have proposed an extension, it has not been approved yet.

Other local cities, like Encinitas and Vista, may offer additional fee waivers or reductions for ADUs. The best way to know what current waiver programs exist in your city is to contact your local building department or work with an experienced ADU contractor. They’ll not only know the building codes and zoning laws pertaining to ADUs but also any fee waiver or incentive programs you can take advantage of. Eligibility for these programs may depend on your income, unit size, and intended usage (rental income, granny flat, etc).

Explore local initiatives and programs in San Diego that offer ADU permit fee waivers to reduce overall project costs.

How Long Does It Take to Get an ADU Permit in San Diego?

A contractor with experience building additional dwelling units will be very familiar with the ADU permit process and can help you obtain a permit in as little as 2-3 months.

Here are the 3 main steps to expect when it comes to ADU permitting:

Step 1: Pre-Application & Planning

Before you can submit a building plan for approval, you have to actually draft the plans themselves. This involves a site or property survey and completing structural designs. Once you have these set to go, you (or your builder) need to fill out all the other necessary documentation needed to actually apply for a building permit.

This initial development process generally takes 1-2 months.

Effective pre-application planning sets the stage for a smoother ADU permit process, enhancing the chances of a favorable outcome.

Step 2: Application Submission & Initial Review

Once your architectural plans and supporting documents are submitted to the city, they’ll do an initial review, looking for potential zoning issues or errors. Under California law, this process can take no more than 60 days or 2 months from the time of submission.

Ensure all ADU permit applications are complete and accurate before submission to minimize initial review time and speed up approval.

Step 3: Revisions and Final Approval

After their 60-day review time, the city must either grant your building permit or require revisions and resubmission. If your city has flagged zoning issues, Title 24 compliance issues, structural modifications, or missing documentation, they’ll need to be fixed before you can resubmit.
After you resubmit, the city has another 60 days to review before returning with final approval.

Timely revisions and adhering to feedback can lead to successful final approvals in ADU projects, avoiding prolonged construction phases.

Expediting the Process: Is It Possible?

One way to expedite the permit process is to use pre-approved plans. Pre-approved plans are already approved by the city for meeting local zoning regulations.

Though there are other factors to consider when submitting for approval, such as setback requirements, these pre-approved plans take a lot of other variables off the table that can prevent a permit from being approved. You can see our pre-vetted floor plans here.

The #1 best way to expedite the permit process, though, is to work with experienced ADU architects. Not only do they have their own pre-approved plans, but their familiarity with the building process ensures that even custom plans meet all the necessary city requirements to keep a project flowing smoothly.

Using pre-approved plans can expedite the ADU permit process, significantly reducing wait times and potential overhead.

Common Permit Delays and How to Avoid Them

The most common reasons for permit delays are documentation errors and zoning conflicts.

Documentation Errors

Cities need to see more than just a floor plan to approve a building permit. There’s a lot of documentation required, including estimated project costs, a site survey, energy compliance documentation, and an application form. If one of these is missing or filled out incorrectly, it can delay your project by months.

Accuracy in documentation can prevent delays. Ensure all forms are meticulously filled to avoid setbacks in ADU permit approvals.

Zoning Conflicts

If your ADU doesn’t meet current zoning laws, it won’t be approved for a permit without a variance. Some of the most common zoning law conflicts include not having the proper setback limits from the property line or other structures on your property, not meeting the size or height requirements, or not meeting the city’s parking space requirements.

Learn more about the zoning laws and building codes for accessory structures here.

Familiarize yourself with local zoning laws to avoid costly conflicts and streamline your ADU project’s approval process.

Solutions

Careful planning is the best way to avoid permit delays. If you’re submitting your own permit for approval, this will likely mean communicating with your city officials early and often to make sure your design ideas meet local codes. If you’re working with a builder, this means choosing one who’s a true ADU expert with extensive experience in Southern California and attention to detail at every step.

Collaboration with seasoned professionals can provide tailored solutions to minimize ADU permit costs and ensure compliance.

Get Started With Your ADU Permit

Don’t let your fear of obtaining a permit stop you from building your dream ADU project. At Better Place Design & Build, we make it our mission to provide our homeowners with a stress-free construction process from start to finish.

To get a rough estimate of the building costs for your construction project, you can use our free cost calculator. For a more accurate cost estimate, schedule a free consultation. We’ll meet, learn more about your goals, survey your property, and provide you with cost breakdowns for every phase of construction, from permitting fees to labor costs to final finish costs, so there will be absolutely no surprises.