Free Tool

Can I Build an ADU?

Answer two quick questions and we'll show you what you can build on your property — allowed types, max size, setbacks, parking, and owner-occupancy — using real rules from your city.

How this works

This checker reads our curated, source-cited ADU rules for 67 US cities — the same data on our city pages — and translates them into a plain-English answer for your property. It's guidance, not a permit determination: always confirm specifics with your city's planning department before designing. We keep the rules current as ADU laws change.

Frequently Asked Questions

Can I build an ADU on my property?

In most cases, yes — if your lot has a single-family or multifamily home in a residential zone, state and local ADU laws likely let you add at least one ADU. The exact size, setbacks, and parking depend on your city. Use the checker above to see your city's rules.

What disqualifies a property from having an ADU?

Common blockers are: a lot below the city's minimum size, HOA covenants that prohibit ADUs (state ADU laws usually don't override private HOA rules), historic-district or flood-zone limits, and lack of utility/sewer capacity. Always confirm with your city before designing.

Do I need owner-occupancy to build an ADU?

It varies by city. Many places dropped owner-occupancy for detached ADUs, so you can rent the unit without living on-site; others still require it. The checker shows your city's rule.

Stay Updated on ADU Law Changes

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