Neighborhood Design and the Environmental and Social Costs of Suburbanization

Abstract

Are the social and environmental costs of suburbanization a consequence of where suburbs are located or of how they are designed? This paper disentangles the two by examining the role of garden city design (GCD), the dominant suburban planning paradigm for US suburbs in the twentieth century, characterized by winding streets, cul-de-sacs and hierarchical road networks. I construct a composite measure of GCD from street layouts and block configurations for over 60,000 neighbourhoods. I then estimate its effects on greenhouse gas emissions, social isolation and sedentary behaviour using ordinary least squares, propensity score matching and an instrumental-variable strategy that exploits historical waves in GCD adoption. GCD substantially worsens all three outcomes. Neighbourhood design accounts for 25–41% of the sustainability costs typically attributed to suburbanization, indicating that how suburbs are designed matters independently of where they are located.