Green roof application on real residential buildings in Tamilnadu, India is very limited and mostly concentrated in major cities mainly for visual purposes. There is not enough research has been conducted to boost up the benefits of green roof system in Warm and Humid weather in India. Green roofs have the potential to improve the thermal performance of a roofing system through shading, insulation, evapotranspiration and thermal mass, thus reducing a building's energy demand for space conditioning. To quantify the thermal performance and energy efficiency of green roofs an experimental investigation was done in residential buildings of Madurai, Tamilnadu, India. This paper refers to the analysis of the thermal properties and indoor thermal performance study of the green roof. The investigation were implemented in two phases: during the first phase, extended surface, air temperature and relative humidity measurements were taken at the indoor and outdoor environment of the buildings where the green roof had installed and during the second phase of the study, the thermal properties of the green roof, as well as, the cooling potential were examined. Results showed vegetative roofs reduced heat gain compared to the white reflective roofs and conventional reinforced cement concrete due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The results also proved that green roofs provide acceptable indoor thermal performance with respect to the other conventional roofs while re-establishing the relationship between human and environment, which have been destroyed due to the rapid urbanization. © 2016 Trans Tech Publications, Switzerland.