ADU permit process in Napa, California
Last verified August 29, 2026
Prepared by GetYourPermit editorial teamReport an error
This guide includes the portions of the City permit process that passed our evidence review. Confirm project-specific requirements with the City before submitting.
Where to apply
- Department
- Building Division
- Permit portal
- City Online Portal System
Step by step
- 1
Confirm City eligibility and special conditions
Use City-linked ADU resources Discuss height, historic, flood/fault, utilities and other site conditions with Planning/Building Building-only or conditional Planning-plus-Building route
- 2
Complete conditional Planning approval
Submit the applicable Planning/Administrative Permit materials Applicable Planning approval or conditions
- 3
Submit paper Building Permit package and plan-review fee
Bring the completed application and required paper plan sets/supporting documents to Building Pay the plan-review fee Full Review intake
- 4
Concurrent City plan review
Wait for Building and applicable departmental review Approvals or coordinated comments
- 5
Respond to comments and resubmit
Address all comments Submit revised plan sets and required resubmittal materials Secondary review
- 6
Obtain sewer and applicable outside clearances
Obtain the Napa Sanitation sewer permit Complete applicable water, utility, Environmental Health, school or other clearances Required permits and clearances
- 7
Complete approvals and pre-issuance documents
Resolve City comments Provide Napa Sanitation verification Complete JADU deed restriction when applicable Obtain remaining clearances Permit ready for fees and issuance
- 8
Pay remaining fees and collect the Building Permit
Pay remaining fees Collect the issued permit, job card and approved plan set Issued Building Permit, job card and approved plans
- 9
Construct under the issued permit
Post the issued documents on site Build to approved plans Submit a formal revision before deviating from issued plans Work ready for phased inspections
- 10
Schedule and pass phased inspections
Schedule by eTRAKiT, automated phone or Permit Technician Keep approved plans and job card on site Do not conceal work before approval Pay an assessed reinspection fee before the next inspection when applicable Signed inspection progress or corrections
- 11
Complete final inspection and Golden Rod clearances
Complete construction and final paperwork Pass Building final Obtain documented Planning, Fire, Public Works and applicable outside-agency approvals Final approval before use/occupancy
- 12
Receive occupancy/permit close-out authorization
Do not occupy until final approval and applicable Certificate of Occupancy are complete Applicable Certificate of Occupancy and permit close-out
What you need to submit
- Residential Building Permit Application
- Paper ADU plan set and supporting documents
- Recorded JADU deed restriction — only in some cases
- Napa Sanitation sewer permit verification
- Golden Rod final sign-off sheet — only in some cases
Pre-approved ADU plans
Use Napa’s official page to confirm which designs, site conditions, and supplemental documents qualify. Plan-check timing still depends on the project and city review.
View pre-approved plansProject-specific next step
Build your Napa permit report
Choose your ADU type and size to bring the City process, researched permit fees, and early construction budget into one planning report.
Sources for this guide
- Accessory Dwelling Units
- Building Division Frequently Asked Questions
- Building Applications, Checklists and Forms
- Accessory Dwelling Unit How-to Permit Guide for Homeowners
- Building Inspection Requirements
- 2026 Junior Unit Initiative Program
- Permits and Plan Review Information
- City of Napa ADU Process Handout
- Revision to Building Permit
Additional city reference pages
The current City-hosted Master Fee Schedule gives an ADU/JADU-specific Building Permit fee and states that this Building fee includes plan review, inspection, fire plan check, and planning plan check.
Accessed August 28, 2026
The live City ADU page confirms that ADUs proceed through an ADU permit application and that pre-reviewed plans still receive City compliance review before Building Permit issuance.
Accessed August 28, 2026