Browse a gallery of real-world ADU floorplans and get inspiration from layouts, storage, and more.
Feasibility Consults
If you’re in a participating community, sign up for our 1:1 feasibility consultations to learn what you need to know about your property, local rules, and what you can build.
Process Map
An overview of the ADU process, from start to finish. (Ask your local planning department if they have a more specific version!)
ADU Workbook
A complete guide to planning an accessory dwelling unit for Napa & Sonoma Counties.
Learn about the ADU rules in your community. (Note: these pages are maintained only for ADU Center member communities – other communities can link to rules summaries if they like.)
Address Lookup Tool
If you want to build an ADU or Junior ADU on your property, use our lookup tool to see what you're eligible to build.
Track your spending and budget throughout the entire project with our easy-to-use tool.
ADU Calculator
Estimate the cost of converting part of your home or constructing a new ADU. You can even use this tool to think through the return on investment (ROI) of building an ADU.
Browse our list of vendors to team with you throughout your ADU project, including finance, design, site preparation, and construction.
Pre-Approved Plans
Search for your local gallery of ADU plans or units ready for purchase (or free use!), saving you time and money. Galleries also include any locally pre-approved plans.