Better sleep, improved health, happier people: how ‘cool roofs’ could help millions avoid deadly heat

The researchers are collecting data from monitors inside houses as well as conducting health tests on participants to determine whether reflective white paint is effective at reducing temperatures inside homes Photograph: Chris de Beer-Procter/The Guardian

The brick house Sylvia shares in a Western Cape township on the outskirts of Cape Town with her three children gets unbearably hot every summer, causing the youngest to cry and her two older children to struggle to concentrate on their homework. Sylvia is not alone, according to a recent report in the Lancet: “In 2024, people in South Africa were exposed to 13 heatwave days, on average. Of these, 10.5 (80%) would not have been expected to occur without climate change.”

But summer is more bearable for the family now that her asbestos roof has been painted with reflective paint.