Cool With Colors: Using Lighter Roof Colors Could Cool the Planet

Anyone who’s crossed a parking lot in August knows that blacktop soaks up a lot of heat. It turns out, rethinking the color of the surfaces around us could help cool the planet.

Roofs and pavements cover 60 percent of urban areas. Scientists from Lawrence Berkeley National Laboratory and the California Energy Commission calculated that lightening their color worldwide could have the same effect on global warming as keeping 48.5 billion tons of CO2 out of the atmosphere. That’s roughly the equivalent of taking every car in the world off the road for 18 years. This elegantly simple solution works because of increased albedo–the degree to which reflective surfaces bounce back the sun’s energy.

Closer to home, color-consciousness does more than fight climate change. Choosing roofing material that absorbs less heat can mean substantial energy savings and may qualify for utility-company rebates. Studies show a “cool roof” can cut air-conditioning bills by 20 percent or more. “It’s not only white roofs” says Michelle van Tijen of the Cool Roof Rating Council. The more than 1,400 products in the organization’s online database come in a range of colors, yet are engineered to reflect more heat than traditional shingles.