Portland describes two separate status questions for older secondary dwellings. An accessory dwelling unit (ADU) built without permits needs a permit and inspection path. A unit once permitted as an accessory rental unit (ARU) may be treated as an ADU under current zoning but still be out of compliance because regulations changed. The City directs owners to a planner for the applicable ARU status question. Neither situation can be resolved by age, a listing, or a history of rental use alone.
If the ADU was built without permits
The City says owners need to get a permit for an ADU built without permits. The building inspector must verify work hidden behind finishes; Portland cautions that verification may involve demolishing or removing elements so the inspector can check that construction was performed correctly and safely. The City does not say that every existing unit can be approved as built, or specify one universal amount of opening-up or correction work.
Before planning repairs, gather permit and property records and ask Portland Permitting & Development which application, plans, inspections, and current code requirements apply. The project’s actual construction and the concealed work determine what the authority needs to inspect. Do not cover work again or assume that an application, inspection request, or permit establishes final approval; check the issued permit conditions and required final inspection.
If the unit was formerly an accessory rental unit
Portland says earlier zoning regulations allowed permits for ARUs and that the City now considers them ADUs under current zoning. It also warns that an older ARU may be out of compliance because regulations have changed, and directs owners to contact a City planner. This is a zoning-status question that is separate from whether the existing building work has the required permits, passed inspections, or meets current building-code requirements.
Ask a planner to review the property’s address, original ARU approval, current use, and any later changes. Then check the building-permit and inspection record separately. A historical ARU permit may be relevant evidence, but the current City guidance does not make it a blanket confirmation that every older unit remains compliant.
Match the records to the unit
For either pathway, compare the address and unit with the original permits, approved plans, later permits, inspection reports, and any open correction items. Ask the City what record will document completion and what scope it covers. For Portland’s broader ADU process and authority links, use the City’s current ADU guidance; for the general method, see how to check whether an existing ADU is legally recognized. Only the responsible City offices can determine what applies to a particular property.