BREAKING DOWN TYPICAL FEES FOR ADU CONSTRUCTION IN ORANGE COUNTY

Building an Accessory Dwelling Unit (ADU) in Orange County is a smart investment—but understanding the ADU construction fees upfront is crucial to avoid budget surprises. Here’s your quick guide to the typical permitting fees, impact fees, and other costs you’ll encounter throughout the ADU process.

What are the typical permitting and impact fees for ADU construction in Orange County?

When planning your ADU, expect to pay a variety of Orange County permitting costs for ADUs, which generally include:

• ADU Building Permits: $2,000 – $5,000+
  (Includes plan check, building, plumbing, mechanical, and electrical permits)

• ADU Impact Fees:
  Waived for units under 750 sq. ft.
  For units 750+ sq. ft., fees range from $3,000 – $15,000 depending on the city and school district.

• Development & Utility Fees:

  • Sewer connection or upgrade: $1,000 – $5,000

  • Water meter upgrade (if required): $2,000 – $7,000

  • School impact fees (typically for units over 500 sq. ft.): $3 – $5 per sq. ft.

Are there any exemptions or discounts available for certain fees?

Yes! Several Orange County development fees can be reduced or waived:

• Impact fees are waived for ADUs under 750 sq. ft. across California.

• School districts may reduce fees for junior ADUs or garage conversions.

• Some cities offer fast-track or pre-approved ADU plans to lower plan check costs.

How can I budget for ADU construction expenses and fees?

Here’s how to plan smart:

1. Get a Feasibility Study Early:
   This identifies site-specific costs like panel upgrades or utility trenching.

2. Separate Soft Costs vs. Hard Costs:

   • Soft Costs = permits, fees, design & engineering

   • Hard Costs = actual construction labor & materials

3. Expect $15,000–$30,000+ in total permitting, impact, and development fees depending on size and scope.

4. Work with a local expert who understands ADU zoning and fee structures in your city.

5. Explore ADU Financing Options:
   Whether you’re considering a HELOC, cash-out refi, or renovation loan, financing your ADU can help spread out upfront costs. Click here to download your copy of our financing guide!

Final Thoughts

Navigating ADU construction expenses can feel overwhelming—but it doesn’t have to be. At ADUs by Avatar, we walk you through every step, from the ADU building permits to final inspections. Want a clear cost breakdown specific to your property?

Contact us for a custom ADU feasibility study.