Can I Build Second Story Addition in Portland, OR? (2026)
Find out if you can build a second story addition in Portland, OR. Rules, permit requirements, costs, and next steps.
Adding a second story in Portland, OR is possible in most zones, subject to height limits and structural permit requirements.
A second story addition is one of the most complex home improvement projects in Portland, OR. It requires a full building permit, structural engineering review, and must comply with the height limits for your zoning district. Unlike a ground-floor addition, a second story changes the roofline and structural load path of your entire home, triggering stricter engineering requirements. In Portland, zone height limits range from varies feet in R20 zones — verify your zone before planning.
Second Story Addition Rules in Portland
Second Story Addition Rules in Portland: Building permit required: Yes — all second story additions require a permit. Example height limit (R20): varies feet. Structural engineering drawings required. Setbacks apply to the full structure height.
Costs & Fees
Contact the local building department for current permit fees. Budget separately for structural engineering.
Next Steps
Next steps for adding a second story in Portland: 1. Hire a structural engineer to assess your existing foundation and framing capacity. 2. Confirm your zone height limit and verify the addition meets all setback requirements. 3. Submit full structural plans and permit application to the local building department. 4. Inspections required at foundation reinforcement, framing, shear panels, and final.
Portland Bureau of Development Services (BDS)
Phone: (503) 823-7300 · Verified July 6, 2026 · Source
Website: https://www.portland.gov/bds
Online Permits: https://www.portland.gov/bds/permits
Frequently Asked Questions
Can I build an ADU in Portland?
Yes. Portland is one of the most ADU-friendly cities in the US. You can build a detached ADU up to 800 sqft in your backyard or an attached ADU up to 75% of your primary home's size (max 800 sqft). Oregon HB 2001 (2019) preempts local restrictions, and Portland eliminated owner-occupancy requirements in 2016. No additional parking is required. A building permit from Portland BDS is required.
What is the difference between Portland's middle housing and ADU rules?
Portland's middle housing rules (implementing Oregon HB 2001) allow duplexes, triplexes, fourplexes, cottage clusters, and townhomes on any single-family lot by-right — these are full dwelling units. ADUs are accessory units added to a lot that already has a primary dwelling. You can combine both: for example, a duplex with an ADU in the backyard could allow up to 3 or more units on a single lot.
Do I need a permit for a home business in Portland?
Yes. A Home Occupation Permit (approximately $80) is required to operate a business from your Portland home. You may have limited client visits (up to 4 per week per business), up to 2 non-resident employees, and must not create external evidence of the business. Oregon also allows cottage food operations (baked goods, jams, etc.) with registration from the Oregon Department of Agriculture.
Can I do Airbnb in Portland?
Yes, with a permit. Portland requires a Short-Term Rental Permit (Type A or B). Type A allows renting your primary residence including entire home when you are away. Annual fee starts at $178. You must display your permit number on listing platforms. Portland collects Transient Lodging Tax (currently 11.5%) — Airbnb remits this automatically. Operating without a permit carries fines up to $500/day.
What are the setbacks in Portland's R5 zone?
In Portland's R5 zone (one of the most common single-family zones), the front setback is 10 feet, side setbacks are 5 feet on each side, and the rear setback is 5 feet. R5 allows up to 50% lot coverage and buildings up to 30 feet tall (2 stories). Verify your specific parcel at PortlandMaps.com — overlay zones, historic districts, or environmental overlays may add additional requirements.
Is solar required on new homes in Portland?
No. Oregon does not have a statewide new-construction solar mandate like California. Solar is encouraged and Portland offers expedited solar permits, but it is not required. The Oregon Residential Energy Tax Credit provides financial incentives for solar installation. Portland General Electric (PGE) and Pacific Power both offer net metering programs.
How do I look up the zoning for my Portland property?
Use PortlandMaps at portlandmaps.com. Enter your address to find your zone designation, overlay zones, flood zone status, historic designation, environmental overlay, and other land use information. Portland Maps is the official City of Portland resource and is regularly updated. You can also contact Portland BDS at (503) 823-7300 or visit the permit center at 1900 SW 4th Ave.
Source: Portland Bureau of Development Services (BDS) — Building Regulations. Last verified April 5, 2026. View source