The City’s new Comprehensive Plan encourages more housing choices throughout the city to accommodate a greater range of family sizes, incomes and ages, as well as the changing needs of households over time. A diverse supply of housing helps to create diverse communities and opportunities for households to remain in their neighborhoods as their lifestyles and housing needs change over time, especially for older adults seeking to age within their communities.
Single houses on individual lots make up more than half of the city's housing stock. Code changes to allow and encourage more housing types in Portland’s single-dwelling zones and other areas are key to increasing housing supply that is affordable to a broad spectrum of households.
The new Comprehensive Plan encourages relatively smaller and more affordable housing near Centers and Corridors and within Inner Ring neighborhoods. Additional study of service availability and infrastructure capacity is needed prior to adopting new housing type exceptions in Portland’s single-dwelling zones.
A house may currently have a single Accessory Dwelling Unit (ADU) that is up to 75 percent the size of the primary house and a maximum of 800 square feet. ADUs can be created from a converted basement or attic, added on to an existing house or built as a separate detached structure. Additionally, duplexes (two units on a single lot) or attached houses (two units, each on its own lot, sharing a common wall on the property line) may be built on corners and on lots bordering commercial zoned lots. In the R2.5 zone, duplexes and attached houses are allowed on any lot that is at least 5,000 square feet in size.
Coined by urban planner Daniel Parolek, the term "missing middle" refers to housing in-between single-family houses and larger multi-family buildings. It can include accessory dwelling units (ADUs), duplexes, triplexes, "smallplexes" and cottage clusters, as well as courtyard apartments, bungalow courts and townhouses. Learn more here.