Building an ADU in California

Know your ADU requirements before you build

Learn what you can build

What ADUs can you build in California

These are the types of ADUs that you can build on residential properties
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Junior Accessory Dwelling Unit (JADU)
A Junior ADU (JADU) is an ADU of no more than 500 square feet. A JADU must be within a proposed or existing single-family home or accessory structure, such as a garage.

Unlike ADUs, JADUs may share a bathroom with the single-family home and must only meet “efficiency kitchen” requirements.
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Accessory Dwelling Unit (attached / detached)
Detached ADUs are located in free-standing buildings that are separate from the main single-family home or multi-family building.

Attached ADUs involve adding on to a single-family home.

ADUs are typically no more than 1,200 square feet.
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Conversion ADUs
Conversions are constructed by converting part of an existing single-family or multi-family home, or by converting all or part of an accessory building (like a garage, shed, or studio). This includes garage conversions.
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Tiny Home on Wheels (THOW)
Description coming soon
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Duplex / Triplex
Description coming soon

Get ADU Financing

Easy, Fast, Low Rate Financing. Explore the top options homeowners use to finance their ADU


Allows homeowners to borrow against the equity in their home to finance the construction of an ADU.

  • Fastest qualification
  • Variable or Fixed Rates
  • Quick to close
  • Pay only on draw amounts

Construction Loan

Construction loans are designed for construction projects where the payment is made directly to the builder.

  • Lowest rates
  • 21-30 days to close
  • Interest only payments for the first 5 years
  • No refinancing to your primary mortgage rate

Unsecured Loan

A type of loan that does not require collateral, such as a home or car. Finance up to $100k without risking foreclosure on the primary residence.

  • Fast Qualification
  • No collateral, uses credit score
  • Up to $100,000
🔒 Get a Secure Financing Quote