As SoCal faces increasingly intense and frequent heatwaves, cities across the County are exploring new ways to keep neighborhoods cooler. Beyond planting more trees and expanding shade, another strategy is gaining traction: making streets reflect sunlight instead of absorbing it.
According to a recent study, one of L.A. County’s hottest neighborhoods is already showing how effective that solution can be. In Pacoima, researchers found that streets coated with a reflective pavement material stayed noticeably cooler during extreme heat.
During a September 2022 heatwave, air temperatures along some treated streets were up to 3.4°F lower than nearby roads with traditional asphalt. The findings come from a year-long study published in Environmental Research Communications, making it one of the most comprehensive real-world evaluations of “cool pavements” to date.
How reflective pavement helped cool Pacoima
The project covered more than 700,000 square feet of streets, parking lots, school grounds, and other paved surfaces using GAF’s DuraShield-SR reflective coating. Unlike traditional black asphalt, which absorbs and stores heat throughout the day, the lighter-colored coating reflects more of the sun’s energy. That keeps pavement surfaces cooler and reduces the amount of heat released into the surrounding air.
To measure the results, researchers monitored the neighborhood for an entire year using weather stations, satellite imagery, drones, thermal sensors, and even an instrument-equipped electric golf cart.
The largest air temperature reductions reached 3.4°F, while on typical hot summer days, coated streets also recorded significantly cooler temperatures. Surface temperatures dropped by more than 16°F in some locations, helping reduce the heat radiating back into the surrounding environment.
The study also found that the reflective pavement did not create significant glare or make conditions less comfortable for pedestrians, two concerns that have often been raised about this type of technology.
