ADU permits · Portland, Oregon
Sourced permit fee ranges, typical approval timelines, and the ADU-specific rules that apply in Portland. All numbers cross-referenced against published builder data and the city's planning department.
Last validated by OwnAdu: May 15, 2026 (manually verified)
Typical permit fees (all-in)
$7,000 – $14,000
Typical approval timeline
~14 weeks
Maximum ADU size
900 sq ft
Parking replacement required
No — exempt under state law in most cases
Owner-occupancy required
No
Setback requirements
Varies by zone; typically 5 ft side and rear
Source: https://www.portland.gov/bds/adu
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