Abstract
Roller blinds are devices that are retracted and wrapped in a box above the window opening and are used to protect against the solar radiation. Those are the wellknown devices with distinct advantages over the fixed external dimming elements. The influence of external blinds on the internal thermal environment in climatic conditions in the Republic of Serbia, the city of Kragujevac, was considered in this research. An external blind was installed in the test room and its influence on the internal temperature was compared with the internal temperature of the room without the blind. Real-time monitoring was carried out in February and August 2023. The results presented in this paper show that the blind reduces the temperature in summer by 3.57ºC and increases it in winter by 1.76ºC. The cooling load can be reduced by about 20%, and the heat load by about 15%.