The aim of this case study is to investigate an integrated heating/cooling system performance in central Europe climate conditions. The possibility of a reliable application of radiant low-temperature heating/ high-temperature cooling ceiling system with capillary mats is discussed. ESP-r, an energy performance simulation program, was used for this purpose. Three types of the buildings are taken into account: a residential building, an office building with small offices and an office building with open space offices. Each of them represents a different operating pattern. The discussion about the results is focused on heating/cooling energy consumption and thermal comfort. The third thing to stress is possible condensation on the ceiling surface during the cooling period.