Overheating in classrooms - sign for inevitable need for cooling or the essential need for integrated design?

In recent years there have been an increasing number of complaints on overheating in class-rooms in Germany. As a consequence some engineers and building operators jump to the con-clusion that there is a need for cooling of these spaces. Based on results from different German projects, based on measurements in existing and retrofitted schools as well as on the basis of dynamic simulations the paper discusses whether overheating is a prevalent issue, pos¬sible root causes of the reported overheating and whether this is caused by the building, the building service systems or their operation. The impact of the improved building envelope composition, optimised for winter conditions in a temperate climate, is discussed. The pos-sible impact of recently implemented mechanical ventilation systems or their operation modes is also highlighted. The examples in this paper show, that there is rather a lack of integrated design and appropriate operation of classrooms than an inevitable need for cooling of classrooms in Germany.