How to Tear Down the Invisible Walls in Your City’s Zoning Code

This is a sidebar to Sightline’s history of the passage of Portland’s residential infill project. In August 2021, Oregon’s largest city legalized duplexes, triplexes, fourplexes and mixed-income sixplexes on the vast majority of residential lots for the first time since 1959, while making on-site parking spaces optional citywide for the first time since 1973. The history was created in partnership with its first publisher, the Lincoln Institute of Land Policy.

These lessons for zoning reformers come from the housing advocates we interviewed about the project’s six-year journey to passage.

1. Show, don’t tell. Never allow anyone to encounter a verbal description of the housing being legalized without also seeing a picture of an example. See Lincoln Institute’s book Visualizing Density and Sightline Institute’s public-domain photo library of “missing middle” housing.
2. Use language carefully. Avoid “density,” which describes the effect of these policies from a city’s perspective. Instead, frame infill around the benefit to an individual: proximity. Avoid “zoning”—“single-family zoning” sounds both abstract and familiar. Instead, use concrete, colloquial language like “it is currently illegal to build a duplex almost anywhere in Portland.” (For other language tips, see our memo on effective pro-housing messages.)
3. Talk about your community’s specific history. Portland advocates tracked down the specific year their city had banned attached homes from most of its land: 1959. Building that year into a pro-housing narrative transformed single-family zoning from “almost-holy abstract concept” into “potentially reversible policy decision.” It also captured some of the class and racial context of exclusionary zoning.
4. Avoid pigeonholes. Take advantage of the fact that housing affects everything. Find unexpected interest groups like AARP, public school districts, energy-efficiency companies, business associations and urban foresters to shape nuanced policies and show public officials the variety of benefits that housing can bring. Don’t let any one type of interest group dominate your membership. This makes more people feel welcome joining.
5. Meet people where they are. Make a good slideshow. Get on organizations’ agendas. Go to their meetings and answer any questions. Never prematurely assume that anyone will be your opponent. Then find your allies and start to strategize.
6. Ally with affordable housing developers. These organizations have the technical expertise, the moral authority and—especially if they own buildable land—a financial incentive to promote better zoning. Organizations that promote homeownership can be an especially good fit.
7. Get a neutral body such as the city government to produce analysis most parties can agree on. At their best, hard numbers transform ideological debates into problems that can be solved and tradeoffs that can be balanced. Also, remember that good local analysis depends on deep knowledge of a place. Qualitative analysis, personal relationships and lived experience inform which questions to ask.
8. Find common ground by thinking bigger. Advocates of market-rate housing and below-market housing can sometimes find themselves at odds. Should fourplexes be legal, but only for below-market projects? When this happens, the answer may be to unite and ask for more: maybe market-rate fourplexes should be legal, and sixplexes should be legal only for below-market projects.
9. Be willing to trade horses. Portland’s zoning reformers found common cause with some NIMBYs by capping the size of one-unit buildings. They found common cause with tenants’ advocates by backing a “tenant opportunity to purchase” program and new rules for screening rental applications.
10. The best day to start building a relationship was 10 years ago; the second best day is today. Portland’s process would have collapsed at many points without healthy relationships between many pairs of people both inside and outside of government. You don’t have to be fast friends. You do have to trust that someone is being straight with you, and vice versa. And you have to have each other’s cell phone numbers.

For a full story about where these lessons came from and how an array of Portlanders put them to work on behalf of future housing, read our history of the passage of Portland’s residential infill project.