Permit Required?
Required
Typical Fee Range
$1,500–$15,000
Fees vary by size; units under 750 sq. ft. are exempt from parkland and school impact fees.
Fee Method
Valuation-based
What's Required in San Jose
- Up to 3 ADUs allowed on single-family lots (max 2 detached)
- Detached ADUs are limited to a 16-foot maximum height
- Minimum 4-foot rear and side setbacks required
- No additional parking required within half a mile of public transit
- Full interior build (kitchen, bath, utilities) must meet 2025 CA Residential Code
- Pre-approved ADU plans are available to reduce design and permitting time
How to Get a ADU Permit in San Jose
1
Step 1: Zoning Verification
Check your property lot size and zoning setbacks for ADU eligibility.
2
Step 2: Plan Selection
Select a city pre-approved plan or hire a professional for custom plans.
3
Step 3: SJePlans Submission
Upload architectural and structural drawings to the SJePlans portal.
4
Step 4: Plan Review
Standard review takes 4–8 weeks for most ADU projects.
5
Step 5: Inspection Series
Schedule the full sequence: Foundation, Framing, Rough MEP, Insulation, and Final.
Frequently Asked Questions
Yes, San Jose allows up to 3 units on single-family lots with streamlined rules.
Building fees start at $1,500; total city fees range from $8,000–$15,000+ for larger units.
Typically 1,000–1,200 sq. ft. depending on your lot coverage and zoning.