The impact of daylight within indoor spaces is intricately linked to the architectural features of buildings, including their surroundings, and overall envelope design, including shading elements like balconies. However, a notable gap exists in the literature concerning comprehensive investigations into the daylight performance and indoor temperature modulation attributed to balconies within apartment structures. This study aims to address this void by examining the impacts of balcony design on the living room of an apartment concerning the indoor thermal environment and daylight performance in warm and humid climate. A case study apartment is chosen at Kotturpuram Chennai to analyze the impacts of balconies in the living space through field measurement and compare the effects of single-glazed and double-glazed balconies through simulation. This research will also explore the balcony design impacts between lower and upper floors to improve occupants’ comfort levels. This study mainly focuses on uniform daylight illuminance (UDI), spatial daylight autonomy (sDA), annual sunlight exposure (ASE), and predicted mean vote (PMV) for accessing indoor environment quality. The findings indicate that the baseline scenario achieves satisfactory daylighting levels, but experiences elevated indoor thermal conditions. However, through simulation analysis, introducing a double-glazed balcony demonstrates a favorable influence on the indoor thermal comfort range. As a result, both visual and thermal comfort levels are effectively attained.