“In Swimsuits, We’re All Equals”: Building High-Rise Cohesion Through Social Infrastructure – The Case of Alt-Erlaa’s Rooftop Pools

Abstract

This study investigates the role of semi-public rooftop swimming pools as social infrastructure in fostering social cohesion within large-scale high-rise housing estates. The research focuses on Wohnpark Alt-Erlaa in Vienna, Austria, a limited-profit housing complex with approximately 10,000 residents that has been widely recognised for its strong sense of community and high residential satisfaction. Using a place-based qualitative case study approach, the research combines semi-structured interviews with residents, a visitor and a facility management employee, participant observation, and qualitative content analysis. The findings identify seven mechanisms through which the rooftop pools contribute to neighbourhood social cohesion: supporting existing friendships and acts of care, facilitating new social connections through shared activities, creating familiarity through repeated encounters, encouraging mutual tolerance, strengthening local pride and identification, fostering solidarity in response to perceived threats, and reinforcing community boundaries through the monitoring of outsiders. The study also highlights the importance of proximity, accessibility, and architectural design features in enabling these social dynamics. At the same time, the research demonstrates that strong local cohesion can produce exclusionary effects and contribute to socio-spatial boundaries between residents and non-residents. The paper concludes that Alt-Erlaa represents a nuanced case combining characteristics of both an open and a closed urban system, while illustrating the potential and tensions of social infrastructure in promoting community life within high-density housing environments.