Skip to Main Content Skip to Sitemap Online Banking

Accessory Dwelling Unit (ADU) Loan

Thinking of adding a dwelling or living space on your residential property for a relative or as an investment? An Accessory Dwelling Unit (ADU) is a secondary smaller dwelling sharing the same ground (or attached to) a larger regular single-family home with its own kitchen and bathroom. You may have heard of an ADU by a different name such as a granny flat, in-law unit, guest house, tiny house, backyard cottage or secondary dwelling unit.

What is an ADU Loan?


ADU loans are temporary, short term loans designed to help borrows finance accessory dwelling units, permitted by their regulatory authority on their owner-occupied property to produce income or to provide for reduced or rent-free familial occupancy.

Loan Term
An ADU loan is interest only, advanced monthly, for a maximum term of 12 months.

Property type
ADU eligible, permitted, existing single-family home, with owner occupied as primary residence.

How to get started

So we can direct you better, lets first find out what phase you are in with getting started on buidling your new ADU.

  1. Are you looking for building ideas, and need direction on how to get started, or have plans but need a project manager? If so, visit Hello Housing (A One Stop Shop for building an ADU) and ask about how they can help you by conducting a remote session to verify the feasibility of building an ADU on your property, and what you need to do to begin exploring this option.  They can help you with design, plans, project management, etc. You can also visit your local planning department to check ADU feasibility and obtain development standards.
  2. Do you already have plans and a project manager and just need financing? Fantastic you are almost ready to get started.  Click here to apply for your ADU HELOC financing and upon receipt of your application a home loan expert will contact you to shedule a consultation. 

Get in touch with a SMCU mortgage expert

Call Email Apply now
(650) 363-1799 [email protected] Get Preapproved Online

Renovations must comply with all applicable state and local laws and regulations, including zoning regulations. All permits and approvals must be obtained. All mortgage loans through San Mateo Credit Union are for homes in California only. Adequate property insurance required for the life of the loan. Flood insurance may be required. All loans are subject to credit approval. Please speak with a Real Estate Representative for current rates and information on loan limits as additional conditions and restrictions may apply. San Mateo Credit Union NMLS #416747.

Home Equity Loan
Build your budget around a predictable loan to pay for major expenses.

We use cookies to improve your experience on our site, enable important site functionality including analytics, site traffic, personalization and marketing. By continuing to user our site, you accept our use of cookies in accordance with our Privacy Policy. Learn more