A considerable part of the energy consumption of buildings is caused by the necessary cooling. Solar radiation represents the largest part of the unwanted heat input. Therefore, considerable costs can be saved and CO2 emissions reduced if energy improvements are made to buildings. Due to the fact that global warming is progressing and the proportion of air-conditioned buildings is increasing accordingly, topics such as energy improvements to buildings, energy savings and energy efficiency are becoming increasingly important. The use of heat protection and thermal insulation is a worthwhile investment with excellent returns.