California Housing Finance Agency
Grant to help income-eligible homeowners build accessory dwelling units (ADUs) on their property. Requires agreement to rent the ADU at affordable rates for at least 5 years. Check CalHFA website for future funding rounds.
Grant toward ADU construction with 5-year affordable rent requirement
Data last verified 2026-06-09. How we verify our data.
A grant-savvy contractor in Castro Valley, CA can handle the paperwork, inspections, and timelines so your funding releases on schedule. Getting matched is free.
You will likely need a contractor to apply
Projects like this almost always need a licensed contractor, and many grants ask for a written estimate as part of your application. Lining up a contractor in Castro Valley early keeps your application moving.
Get matched with a contractorEach program sets its own contractor rules. Check the official program page for exact requirements.
The CalHFA ADU Grant reimburses up to 40,000 dollars of the predevelopment and non-recurring closing costs of building an accessory dwelling unit, such as site prep, architectural designs, permits, soil tests, impact fees, and surveys. You apply through a CalHFA-approved ADU lender or participant. Funding is released in rounds, so confirm a round is currently open before you count on it.
Steps to apply
Documents you will likely need
Requirements vary by program and locality. Confirm the exact rules on the official program page. We can help you prepare your paperwork, but you submit it yourself.
Deadline: Program closed; check for future rounds
Ask us. It is free, and a real person answers within a business day.
Email us about this programGrant-approved contractors understand the documentation, inspections, and timelines, so your funding releases on schedule.
Rebates and discounts that stack on top of any grant. Most are free to use.
This is just one of many grants, rebates, and free programs available. Stack them together to maximize your savings.
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