This study uses Computational Fluid Dynamics (CFD) simulations to optimize the indoor thermal environment in a computer lab at a civil engineering department in Madurai, Tamil Nadu, India, characterized by a hot semi-arid climate by evaluating different roof and Heating, Ventilation, and Air Conditioning configurations using CFD simulations and to examine the thermal comfort and indoor air quality. The goal of the study is to comprehend how various roof materials and air conditioning affect the temperature, air dispersion, and thermal comfort of the room. Autodesk Revit was used to construct three scenarios, while Autodesk CFD and ANSYS Fluent were used for analysis. The findings of the study provide the use of gypsum-board roofing combined with AC for optimizing thermal performance for the design of educational facilities, since they emphasize how important air conditioning and material choices are to attaining the best possible thermal comfort. Scenario III (AC + Gypsum roof) showed a 24% temperature drop compared to Scenario I (RCC roof), and 15% better thermal distribution than Scenario II.