Multnomah County • Permissiveness Score: 98/100
Portland, OR ADU Zoning Rules & Regulations
Portland permits two ADUs per lot under its Residential Infill Project (RIP). System Development Charges (SDCs) are permanently waived for qualifying ADUs.
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Key Zoning Parameters for Portland
Verified 2026 Max Detached Size 800 sq ft
Max Attached Size 800
Rear & Side Setbacks 5 ft rear / 5 ft side
Front Setback Must match standard front building line
Max Height Limit 20 feet (2 stories)
Owner Occupancy Not Required (Waived) Owner occupancy requirement removed completely.
Parking Requirements Exempt No off-street parking required citywide for ADUs.
Junior ADU (JADU) Not recognized
Short Term Rentals (Airbnb) Allowed with permit Type A and Type B accessory short-term rental permits available.
Estimated Permit Fees $2,500 - $6,000 (SDC waivers can save $10,000+)
Avg Review Timeline 4 - 8 weeks
Fire Sprinklers Only if primary dwelling has sprinklers.
Governing Ordinances & State Laws
- ✓ Portland Title 33 Planning and Zoning
- ✓ Oregon HB 2001
- ✓ Portland RIP (Residential Infill Project)
Portland ADU Frequently Asked Questions
Does Portland waive System Development Charges (SDCs)?
Yes, Portland offers permanent or continuous SDC waivers for ADUs that agree not to be used as short-term rentals for 10 years, saving homeowners $10,000 to $17,000 in permit fees.
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