Alofi

Increasing heat exposure caused by climate change is affecting communities worldwide, especially those living in poor housing conditions such as informal settlements and low-income households. This research aims to study the impact of applying sunlight-reflecting cool roof coatings on indoor temperatures and overall health. The trial is a global, multi-center, cluster-randomized controlled study conducted in five urban climate hotspots across Africa, Asia, Latin America, and Oceania, where heat exposure and vulnerable housing conditions pose significant health risks. The study compares households that receive a cool roof coating, which reflects sunlight and reduces indoor heat, with those that keep their original roofs. The cool roof coating works by reflecting ultraviolet and visible sunlight and radiating absorbed heat, thus lowering indoor temperatures and energy use. The trial will run over a 12-month period, including the hottest months of the year, to measure the effects on health, indoor environment, and economic outcomes. Participants will undergo repeated measurements including resting heart rate, blood glucose control, depression symptoms, and various health and environmental factors over the course of the study. Data will be collected at baseline and multiple times during the hottest months and alternate months. Researchers will monitor indoor air temperature, humidity, heat index, and household energy use continuously. The study seeks to provide evidence on whether cool roofs can improve physical, mental, and social wellbeing in vulnerable populations facing extreme heat.