In an effort to boost housing density and affordability, Oregon has updated its building code to allow a new type of housing—stacked duplexes. The Oregon Building Codes Division officially adopted temporary rules on Jan. 31, with permanent adoption set for April 1.

The new provisions define stacked duplexes as “a vertically stacked, two-family dwelling where one of the dwelling units is located above the other dwelling unit and access to a yard, street, alley or public way is provided on not less than two sides.”

These code updates enable stacked duplexes to follow existing townhouse regulations, making it easier to double housing units in areas seeking greater density. This change also simplifies the construction process, allowing for more infill development on smaller lots while ensuring safety and compartmentalization standards remain intact.

Gov. Tina Kotek praised the move as a creative solution to Oregon’s housing crisis.

“Addressing the housing affordability crisis means looking under the hood for every fix we can find,” Kotek said. “I appreciate the Oregon Building Codes Division’s creative work. This change will give more Oregon families access to more affordable options.”

Previously, stacked duplexes were subject to stricter and more complex building codes, as they had to comply with multifamily housing standards under the structural specialty code. The new update streamlines the process, reducing costs and regulatory burdens for builders.

Howard Meadows, a new subdivision near Howard Elementary School in Eugene, is among the housing projects that could benefit from these changes. Planned to feature 12 lots of fourplex townhomes, the development aligns with the city’s broader efforts to expand middle housing, including duplexes, townhomes, and cottage clusters.

Alana Cox, administrator of the Building Codes Division, emphasized the importance of the update in helping meet Oregon’s housing needs.

“It will allow for creating more units in a simpler, more streamlined way while still ensuring safeguards are afforded in design,” Cox said. “The governor has called for an all-hands-on-deck approach and we have been working with the Residential and Manufactured Structures Board, industry partners and local governments to come up with innovative solutions.”

Eugene planners are currently working on long-term Urban Growth Strategies to accommodate job growth, housing demand, and community expansion through 2049. With the new code in place, stacked duplexes could become a key tool in addressing the region’s need for more affordable and flexible housing solutions.

Originally reported by Hannarose McGuinness in The Register Guard.