The Plex Paradox
- Josh Stephens
- Jun 21, 2021
- 6 min read
For all the qualitative and quantitative complexity of planning, perhaps the biggest trend facing California in the coming years relies on very simple math: what is one divided by one-half?
The answer, of course, is a duplex. But, with variables including everything from lot sizes to neighborhood character to topography to historical patterns of segregation and inequity, the calculation for many California cities is going to be anything but simple.
Last week, CP&DR, along with the Terner Center for Housing Innovation at UC Berkeley and the California Chapter of the American Planning Association, convened a panel entitled "The -Plex Paradox: Writing the Code to Undo Single-Family Zoning" to discuss exactly what combination of art and science will be required for cities to undo single-family zoning and instead allow small multifamily dwellings -- be they duplexes, triplexes, or more -- to be built, either by conversion or new construction. (A video of the event is available here.)
Several California cities, including Sacramento, and Oakland -- which were represented on our panel, have either passed or are considering or have adopted policies to do away with single-family zoning. Senate Bill 9, which made it out of its chamber of origin and is now being discussed in the Assembly, would take the trend statewide.
Portland was also represented on the panel – because the Oregon city is far ahead of any California city in adopting a nuanced approach to ending single-family zoning.
Portland's Residential Infill Project was adopted in January 2020 and goes into effect August 1. Sandra Wood, a principal planner in the Portland Bureau of Planning and Sustainability shared highlights of the five years’ worth of work -- dating back to the projects’ inception in 2016 -- to draft an effective ordinance that promotes what she described as "missing middle housing." Portland's program includes multiple building categories, which vary according to number of units and the inclusion of accessory dwelling units, and detailed requirements for massing, setbacks, and other design-related elements that will or will not be allowed depending in large part on the size of the lot being developed.
Wood offered advice for California planners: minimize the typologies. For instance, the RIP distinguishes between a development of a triplex and a duplex-plus-ADU. She said, "why not just 'three units'? We got too persnickety about the types of units on the sites. In retrospect, I wish we'd been more simple."
