This study evaluates the ability of TRNSYS software to simulate the impact of orientation and floor level on indoor temperatures in a building located in Marrakech. The analysis shows that south- and northeast-facing areas tend to be warmer due to solar exposure, while north-facing zones remain cooler. Additionally, the upper floor experiences higher temperatures due to thermal stratification. TRNSYS demonstrated its effectiveness in accurately simulating temperature variations across different zones of the building. This study highlights the software’s potential for modeling complex thermal behavior, taking into account factors such as solar gains, ventilation, and building characteristics. These results contribute to future research aimed at optimizing building design by improving energy efficiency and thermal comfort. Strategies like enhanced insulation, solar protections, and natural ventilation could be implemented to reduce energy consumption and improve indoor conditions, creating more sustainable and comfortable living environments.