Investigation of a Ventilation System for Energy Efficiency and Indoor Environmental Quality in a Renovated Historical Building: A Case Study

This paper emphasizes the importance of environmental protection regarding the reduction of energy consumption while maintaining living standards. The aim of the research is to observe the effects of mechanical and natural ventilation on energy consumption and building operation as well as indoor environmental quality (IEQ). The results of indoor environmental quality testing show that the mean relative humidity (31%) is in the permissible range (30%–70%); the mean CO(2) concentration (1050.5 ppm) is above the recommended value of 1000 ppm according to Pettenkofer; and the mean PM(10) concentration (43.5 µg/m(3)) is under the limit value of 50 µg/m(3). A very large positive correlation is found between relative humidity and concentration of CO(2) as well as between the concentration of PM(5) and the concentration of CO(2). The most commonly occurring sick building syndrome (SBS) symptoms are found to be fatigue and the feeling of a heavy head.