Symbium Build is a free, online tool to help you figure out if an ADU makes sense for you
No matter what you call them — accessory dwelling unit, second unit, in-law unit, granny flat, casita, and backyard home — ADUs are a great way to raise your property value and earn extra income while building much-needed housing.
Learn about ADUs
Learn instantly if you can have an ADU on you property
Get instant answers to questions like: “Can I build an ADU on my property?,” “How big of an ADU can I build?,” “Can I rent out my ADU?,” and much more.
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Find an ADU design that fits your property, complies with regulations, and suits your needs
Explore different ADU designs. Place them onto a map of your property. See how they suit your property and meet regulatory requirements. Find and connect with builders and design professionals.
Understand the next steps to getting your ADU designed, approved, and built
Learn the rules and process to follow. Get easy-to-understand information about key issues, like the cost of an ADU and the timeline for getting one built.
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Symbium Build covers the entire state of California
58 Counties
482 Cities
12.6M Properties
39.5M in Population
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Frequently Asked Questions