Junior ADU (JADU) in San Mateo, CA
Convert a bedroom into a compact 500 sq ft junior ADU within your home.
About Our Junior ADU (JADU) Service
A Junior ADU (JADU) is a compact living unit of up to 500 sq ft created within the existing walls of your house — typically by converting a bedroom and adding an efficiency kitchen and a private entrance. JADUs are the most economical way to add a rentable or multigenerational unit because they reuse existing space and often share a bathroom with the main home. California allows a JADU in addition to a standard ADU on many single-family lots, so some San Mateo homeowners build both. We handle the entrance, kitchenette, and any required interior separation to code.
What's Included
Our Process
Space Review
We identify the best room or corner of your home to convert into a self-contained junior unit.
Permit Plans
We draw the JADU layout with the required kitchenette and entrance and submit for permit.
Conversion
We add the private entrance, efficiency kitchen, and any interior separation between the unit and main home.
Final Inspection
We finish and pass inspection so the JADU is legal to occupy or rent.
Why Junior ADU (JADU) Matters
- Most affordable ADU option
- Reuses existing interior space
- Fast, low-disruption conversion
- Can be combined with a detached ADU
- Great for family or modest rental income
Frequently Asked Questions
What is the difference between a JADU and an ADU?
Can I have both a JADU and an ADU?
Does a JADU need its own bathroom?
Junior ADU (JADU) Service Areas
We provide junior adu (jadu) across San Mateo and the Peninsula, including:
Get a Free Quote
Free on-site estimate
Starting at
$45,000
Interior JADU conversion, based on kitchen and entrance scope.
Duration
2 - 4 months
Warranty
1-year workmanship warranty
Other Services
Why Choose Us
- Licensed & Insured
- Satisfaction Guaranteed
- Free Estimates
- San Mateo Local
- Design-Permit-Build
- 1-Year Workmanship Warranty