How carsharing services in residential housing impacts modal split and car usage – a multi-method investigation including legal challenges

This study investigates the complex interplay between environmental concerns, urban mobility challenges, and legal intricacies associated with car ownership with a focus on Austria, Germany, and Switzerland. Carsharing (CS) emerges as a key element in transport systems, particularly in residential areas, aiming to reduce car dependency, reduce parking spaces, promote increased public transport usage, and reducing traffic congestion.The study explores whether CS induces a modal shift, how many cars can be replaced with a CS-vehicle, if developers can save parking spaces and thus construction costs through CS services, and what the legal landscape for parking and CS is in Austria. The research uses a multimethod approach, including a systematic literature review, semi-structured interviews, desktop research on existing carsharing projects in residential housing, and an examination of legislative aspects in Austria.Findings suggest that around 25% of analysed papers explore the connection between CS and housing. Interviews highlight key enablers for CS, including good public transport access, strategic placement of CS hubs, and the availability of e-cars. Experts specializing in the carsharing field suggest on average 12 cars can be replaced by one CS vehicle. Projects implemented in Austria, Switzerland, and Germany, where CS costs are shared among tenants or mobility fees are incorporated into rent, indicate the viability of this approach. Additionally, projects in Switzerland that regulate car ownership in lease contracts suggest the potential for reducing parking spaces by offering adequate alternative mobility options. CS is explicitly addressed only in Vienna's garage law, permitting the reduction of mandatory parking spaces. In other Austrian federal states, it is generally subject to case-by-case evaluations.