Carsharing and Car Ownership at the Building Scale

Problem, research strategy, and findings: A number of studies across the world have established the potential of carsharing to reduce vehicle ownership and parking demand at the citywide or neighborhood scale; however, few North American cities have formally adopted reduced minimum parking requirements for developments with carsharing services onsite (i.e., dedicated carshare vehicles). This reflects the lack of evidence regarding the impacts of carsharing on individual developments, as well as the implementation and enforcement challenges associated with adopting more flexible parking requirements. This article investigates the case for developing and implementing a reduction in the parking requirements for residential buildings that provide dedicated carshare vehicles. We use surveys of residents of buildings with and without dedicated carshare vehicles in Toronto, Canada, to develop a regression model of vehicle ownership. This analysis suggests that the presence of dedicated carshare vehicles is associated with reduced vehicle ownership and parking demand at the building level. This is the first study, to the authors' knowledge, that quantifies this relationship at the scale of individual developments. Takeaway for practice: This article provides recommendations for developing a parking reduction ratio for carsharing that is compatible with existing parking requirements. It also considers approaches to promote the long-term financial viability of dedicated carshare vehicles. Overall, this study provides a starting point for those considering if and how to relax parking requirements for developments with access to carsharing services and illustrates some of the challenges with adopting flexible parking requirements. Research support: The City of Toronto.