Ljubljana’s experience calls for a reassessment of the traditional concept of building energy performance, shifting the focus from technical parameters to the real-life experience of users. Through the Efficomfort project, the city explores a model in which comfort — understood as indoor environmental quality, health, and well-being — becomes a measurable and manageable service, integrated into the day-to-day operation of buildings.

This approach is structured through close collaboration between institutional, technical, and social actors, reflected in the contributions of Nuša Muršič from the City of Ljubljana, alongside Jure Vetršek and Primož Medved from the Institute for Innovation and Development of the University of Ljubljana, and Urban Jeriha and Karina Sirk from the Institute for Spatial Policies. Their perspectives highlight that integrating technical knowledge and social experience is key to adapting solutions to real-world usage needs.

The model combines energy efficiency, real-time monitoring, and participatory processes that enable indoor conditions to be adjusted based on behaviour and preferences. In this context, comfort shifts from being a passive outcome to becoming an operational objective, with potential for replication in other European cities.