Combating Climate Change-induced Heat Stress: Assessing Cool Roofs and Its Impact on the Indoor Ambient Temperature of the Households in the Urban Slums of Ahmedabad

BACKGROUND: The rising global temperature and frequent heatwaves are the adverse effects of climate change. The causalities and ill impacts of the heat stress were higher among the slum dwellers because of the vulnerable household structures, which were made by heat-trapping materials like tin sheets, cement sheet (asbestos), plastic, and tarpaulin. The houses are not only dwellings but also a source of livelihood for many slum dwellers as they are involved in home-based work. The increase in the temperature of more than 40°C severely affects health and increases energy expenditures. OBJECTIVE: The present study conducted to identify the efficient cool roof technologies that reduce indoor temperature of the households and improve the heat resilience of dwellings located in the urban slums of Ahmedabad. METHODOLOGY: The performances of cool roof interventions were compared with the nonintervention - roof types, namely, tin, asbestos/cement sheet, and concrete. Relative humidity/temperature data loggers (Lascar EL-USB-2-LCD, Sweden) were used to measure the indoor ambient temperature and humidity. The questionnaire-based survey also has been conducted to understand the socioeconomic status and the perceptions related to roofing and health. RESULTS: The results revealed that selected cool roof technologies including Thermocol insulation, solar reflective white paint on the outer surface of the roof, and Modroof are effectively reducing the indoor temperature as compared to the nonintervention roofing. CONCLUSION: Cool roof technologies have a wider scope as number of informal settlements are increasing across the cities in India and other developing countries. The governments may not able to provide proper housing to all these inhabitants due to various reasons including the land tenure of the habitats. Validated cool roof technologies can be promoted as these structures are not requires legal sanctions and easily dismantled and installed in multiple places and safeguards the investment of urban poor.