Air conditioning within public and historical buildings, which include ceremonial, official, and religious structures, must account for differing architectural and usage variants. Depending upon the application the HVAC systems must be able to reach full functionality quickly, work for short periods and be switched off or at partial capacity in the interim. They often present low surface/volume ratios, high ceilings and usage patterns which at times are very inconsistent. The most common HVAC solutions are air handling units, provided that the necessary ducting is aesthetically acceptable and relatively compact. To limit winter stratification in high ceiling structures, and the potential discomfort caused by vertical temperature gradients, the outlet temperature is reduced and the air flow rate increased, ensuring an adequate air circulation. When the equipment cannot be located externally or noise levels are an issue, so air handling units with plug fans or low noise fans, or alternatively water-cooled hydronic units, can be applied. With a wealth of specific experience accumulated over several decades, Aermec is an expert, reliable partner in the development of optimal solutions for buildings of great historical and cultural value.