Estimating the indoor heat stress of low-socioeconomic status households in Jalna district of Maharashtra (India)

Projections regarding climate change indicate that globally, densely populated areas are poised to witness a heightened frequency of more severe and prolonged heat waves. Indoor conditions, including housing roofs, and circulation systems significantly influence the impact of heat-related issues and discomfort. Literature on heat-related vulnerability studies often lacks substantial references to these factors. This study seeks to comprehend the influence of various roof types on heat risks in a semi-arid region village in Maharashtra, India. The study uses indoor data loggers to observe temperature & relative humidity in different housing conditions. Wet-Bulb Globe Temperature (WBGT) is derived to evaluate heat-risk exposure in indoor environments. Findings reveal that dwellings with tin roofs experience higher and more prolonged heat risks compared to Reinforced Cement Concrete (RCC) or thatch roof houses. Moreover, RCC and tin roofs exhibit increased exposure during the day WBGT (5-7 °C higher during night WBGT), whereas thatched roofs display minimal daily WBGT variation, indicating robust heat resilience. Ceiling fans consistently lower indoor WBGT and thus reduce heat‑risk hours across all roof types, though their effectiveness varies by time of day and housing material. Fans offer cooling benefit in the early morning from 12 am to 10 am and late evening hours from 7 pm to 11 pm. Ceiling fans reduce indoor WBGT by approximately 1.1°C in tin‑roof houses, 1.4°C in thatched houses, and 1.5°C in RCC houses, demonstrating their pronounced cooling efficacy during these heat periods.