Amidst sustainability challenges and in an increasingly urbanised context, housing design qualities are crucial to promote residents’ wellbeing. Despite the role balconies play in establishing connections with the surrounding environment and enhancing housing qualities, questions around how to design balconies that meet users’ needs remain under-characterised. An online survey and analysis of Finnish residents’ (n = 393) attitudes to and uses of their balconies is presented. This provides improved insights into and understanding of the implications of glazed balcony design on housing qualities and users’ wellbeing. The subjective data are analysed in three steps via summary statistics, content analysis and co-occurrence analysis. Results reveal that balconies are greatly used, and that glazed enclosures of balconies—a specific characteristic in Finland—enhance the balconies’ space functionality throughout the year. However, glazed balconies are perceived to be potentially harmful to overall indoor environmental quality, increasing overheating risk, and reducing daylight and purge ventilation in the living space if not used as designed. This study shows the need for a user-oriented approach to design balconies that enhance housing qualities and users’ wellbeing. Practice relevance Balconies in Finland play an important role in inhabitants’ health and wellbeing. New insights from this study about how inhabitants use their balconies will enable developers, landlords and architects to make more effective decisions about the designs of balconies and dwellings generally: size, location, ventilation and configuration of balconies. Overheating is a significant issue limiting balcony use. Significant differences arise for balconies located on lower or upper floors: those on higher floors are more vulnerable to overheating. Architects should not take for granted that implementing passive strategies will mitigate the risk of overheating. This suggests that landlords/building owners should provide information and guidance to inhabitants on how to use glazing more effectively in both winter and summer.