With COP31 now underway in Türkiye, a straightforward fix is being trialed to assist South Africans with heatwaves: whitening shack roofs. Preliminary data indicates this reflective roof paint can cut indoor temperatures by 3–5°C when the sun is at its peak, possibly enhancing rest for those in informal dwellings.
A Cooler Home, Better Sleep
In Khayelitsha, Cape Town, and Mphego village near Thohoyandou, scientists are applying a special coating to roofs that reflects sunlight instead of absorbing it. This small-scale experiment could have a significant impact, offering a practical solution as world leaders gather for COP31 to address climate change and health. The World Health Organisation emphasizes the urgency of protecting populations from climate-related health threats, making initiatives like this key.
The project aims to prevent homes from becoming unbearably hot during the day, ensuring residents can sleep more comfortably at night. According to the 2025 Lancet Countdown report, South Africans experienced an average of 13 heatwave days in 2024. This highlights the growing need for such interventions.
The Impact of Heat on Sleep
Climate change, driven by the release of gases like carbon dioxide, is causing hotter days and warmer nights, disrupting sleep patterns. The body requires a cooler environment to lower its internal temperature and fall asleep. A 2022 study analyzing 7 million sleep records from 68 countries found that rising nighttime temperatures reduce sleep duration, particularly in poorer nations. Regularly poor sleep increases the risk of conditions such as high blood pressure, diabetes, heart disease, and depression.
In South Africa, where 1.4 million households live in informal dwellings, escaping the heat is a significant challenge. University of Cape Town epidemiologist Lara Dugas is leading the roof-painting study. In Khayelitsha, residents often go to bed early due to safety concerns but experience fragmented sleep.
People in Khayelitsha spend an average of 11 hours in bed but struggle with poor sleep quality due to heat and unsafe environments.
Long-Term Benefits and Community Impact
The reflective roof paint offers a durable solution for cooling homes. Proper roof preparation is key for maximizing its lifespan. Researchers are also exploring additional solutions to further enhance cooling.
Partnerships and Future Expansion
The study, which began in 2022 and is set to conclude in 2027, has already painted 120 roofs across 240 households. Its success could pave the way for wider adoption, offering relief to millions in informal settlements across South Africa and beyond.