Are Portland ADU rules different from DADU rules?
Answered by AskBaily Editorial · Updated
Short answer
Yes. Portland defines an ADU as any accessory dwelling unit (attached conversion of basement/upper floor or garage) and a DADU as a detached accessory dwelling unit. Both are now allowed on most R-zoned lots under RIP and prior ADU liberalization. Attached ADUs are typically cheaper ($95K-$225K) because they reuse existing structure; DADUs run $180K-$400K for new detached construction. Permit tracks differ slightly.
In detail
Yes. Portland defines an ADU as any accessory dwelling unit (attached conversion of basement/upper floor or garage) and a DADU as a detached accessory dwelling unit. Both are now allowed on most R-zoned lots under RIP and prior ADU liberalization. Attached ADUs are typically cheaper ($95K-$225K) because they reuse existing structure; DADUs run $180K-$400K for new detached construction. Permit tracks differ slightly.
This answer is part of AskBaily's portland regulatory knowledge base. For deeper context — including current code-section references, agency contact details, and recent policy changes — see the [portland city hub](/portland) or [the /ask hub](/ask) for related questions.
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