A Comparison of Thermal Comfort of Old Indigenous Houses with New Residential Buildings of Kolkata, India

Earth has experienced a global warming of 1.09 degree C over the last two decades when compared to the previous century.This problem has become multifold in the urban areas, thus generating the new phenomenon of "urban warming" as quoted by the IPCC.According to the IPCC data sheet of 2018, the city of Kolkata remains at the top of this urban warming list (2.6 degree C).Majority of this urban warming is contributed by buildings.The residential buildings of Kolkata, which constitutes the lion's share of the total built mass contributes considerably to this warming.As the global warming phenomenon has been mostly observed from 1970 onwards, this research assumes that buildings designed and built after that year has larger contributions to it.Hence, this research examines the thermal performances of samples of old (100 years of age or older) and new (after 1970) residential buildings of Kolkata, and compares them to find out which group performs better than the other.The research focuses on non-air-conditioned housing stocks and collects data on temperature, relative humidity, air velocity from the sample houses as well as does measured drawings of the same.It then uses the composite indexes of heat index, percentage comfort hour and comfort fraction to analyze the collected data and compare the two groups of residences.Based on this analysis, it is concluded that the internal thermal performance of the old residential buildings are better than those of the new residential buildings.