Reflective Paint Cools African Homes by 7°F in Summer Heat

When researchers went looking for heat adaptation projects helping low-income African communities cope with rising temperatures, they found absolutely nothing to study. So epidemiologist Lara Dugas and climate scientist Mark New decided to create one themselves.

They chose a South African reflective paint called Rhinoluxe Heat Reflect, originally designed for chicken coops and warehouses. Over two years, teams painted roofs across four sites in South Africa and Ghana, from Cape Town's largest township to rural villages.

The results changed lives immediately. Temperature sensors in 240 homes tracked three summers of data and found painted roofs kept indoor spaces three to four degrees Celsius cooler during the hottest parts of the day.

For Sylvia, a single mother in Khayelitsha, that translates to something priceless: her children finally sleep. Her brick house had been unbearable every summer, with her youngest crying from heat and her older children unable to focus on homework. "My children sleep better," she says. "For me, that means everything."

Bongani, whose roof hasn't been painted yet, knows exactly what Sylvia gained. His zinc house traps heat into the night, leaving him so exhausted and angry he can't think straight. When temperatures spike, he walks to a friend's house with a painted roof just to get relief.

Why This Inspires

Sleep became the health metric the project watches most closely, and for good reason. Building scientific links between heat and chronic diseases takes decades, but sleep disruption shows up within the first season.

"Bad sleep has poor mental health outcomes, poor disease outcomes, and makes diseases that are already present much worse," Dugas explains. The team fitted participants with sleep monitors, core body temperature sensors, and tracked everything from blood pressure to air quality.

The timing couldn't be more critical. A 2025 Lancet report found South African residents endured an average of 13 heatwave days in 2024, with 80 percent of those days impossible without climate change.

Postdoctoral researcher Vuyisile Moyo spent three summers walking between painted and unpainted houses in Khayelitsha, watching the difference firsthand. His vision for scaling up is practical: "In an ideal world, every one of these roofs would be painted. But we should start by painting schools and clinics."

For Dugas, the project reoriented her entire career. "When you paint a roof you can change people's lives in an instant," she says.

The formal health data is still being compiled, but the evidence base that didn't exist before now has a foundation to build on.