With the rise in problems mainly ecological as well as energy crises that are intensifying today, the concept of green has become essential concerning sustainable development. The hospital building consumes much more energy and generates more waste, as compared to the other types of buildings. The climate change, contamination of chemicals, and use of unsustainable resources are all making health worse day by day over the world. The health sectors are themselves causing these problems on a broad scale. So, hospitals, health sectors must be green, there must be proper management of resources, waste etc., which means that it must have a minimum negative impact on the environment. The term Green Hospital has evolved as a way of addressing environmental issues, overcoming them and meeting society’s need. In India, Green Rating for Integrated Habitat Assessment (GRIHA) is one of the tools that provides green building certification to hospital buildings also. This paper aims at analyzing and investigating a hospital building (Trauma centre), Jawaharlal Nehru Medical College, Aligarh, based on major criteria of the GRIHA variant for existing buildings. This hospital building had been provisionally-rated by GRIHA in the year 2016 as 3 stars. This paper includes the analysis of building based on various calculations and in depth study of how this 3 star rating was provisionally achieved. This paper involves two main calculations, one regarding peak heat gain and the other is EPI.