The Effects of Form-Based Zoning: An Analysis of Miami 21

Abstract

Economists posit that zoning generally has exclusionary effects. Planners, politicians, and economists claim that the newest trend in zoning, form-based zoning, does not have the same exclusionary effects that result from traditional zoning codes. Miami was the first city to implement a comprehensive form-based zoning code, the Miami 21 Zoning Code, and it serves as the foundation of this paper’s examination of form-based zoning’s exclusionary effects. I use the American Community Survey’s 1- year and 5-year estimates in an interrupted time-series model to study the impact of Miami 21. I look at Miami’s trends in key demographic statistics over time, and I also compare Miami to the control cities of Atlanta, Tampa, and Los Angeles. The results show evidence of income-related trends that mirror the exclusionary trends in cities with traditional zoning codes. However, race-based exclusionary effects of the new zoning code are not clear.