ADU Permitting Portland: Step-by-Step Guide to Approvals

Getting an ADU approved in Portland requires navigating zoning codes, building permits, and inspections.
A clear understanding of the permitting process saves time, avoids delays, and ensures your project complies with city requirements.

Why Permitting Matters for ADUs

Even if your lot and design seem compliant, permits are mandatory for any ADU construction or conversion.
Unpermitted work can result in fines, forced modifications, or even demolition.
Starting with proper approvals protects your investment and ensures safety.

Step 1: Confirm Zoning and Lot Feasibility

Before submitting any permits, verify that your lot allows an ADU and meets minimum setbacks, height restrictions, and lot coverage limits.
The ADU Feasibility Wizard quickly evaluates zoning and site constraints to confirm if your project is viable.

Step 2: Prepare Required Documentation

You’ll need detailed site plans, floor plans, and structural information. Documentation typically includes:

• Lot survey and property boundaries
• Proposed ADU drawings (floor plans and elevations)
• Structural calculations for detached or above-garage ADUs
• Site grading, drainage, and utility connections

Step 3: Submit Permit Applications

Portland permits can be submitted online through the city’s Development Services portal. Depending on your ADU type, you may need:

• Building permit
• Plumbing and electrical permits
• Mechanical and energy compliance
• Fire and safety review (if applicable)

Step 4: Schedule Inspections

Once work begins, inspections ensure compliance with approved plans. Typical inspections for ADUs include:

• Foundation and footings
• Framing and structural review
• Plumbing, electrical, and mechanical inspections
• Final inspection before occupancy

Step 5: Final Approval and Occupancy

After all inspections pass, the city issues a certificate of occupancy, confirming your ADU is legally habitable.
This step completes the permitting process and allows you to rent or occupy the unit safely.

How the ADU Feasibility Wizard Helps

The ADU Feasibility Wizard streamlines the early steps of permitting by confirming zoning, setbacks, and lot feasibility.
For a $250 upgrade, you can download preliminary plans or upload your own to ensure your ADU meets city requirements before investing in full construction drawings.

Start Your ADU Permitting Process Today

By understanding each step of the ADU permitting process in Portland, you can reduce delays, avoid redesigns, and move forward confidently.
Use the ADU Feasibility Wizard to verify lot compliance, confirm zoning allowances, and prepare your permit submissions efficiently.