There is another way to make a green roof and it's white. Instead of covering the entire surface of a building roof with plants, there is another way that is both green and white, with paint. Read more about it in the article below.
The bottom photo shows the roof of celebrity chef Rick Bayless’s Frontera Grill in Chicago. The roof is edible green with EarthBox type sub-irrigated planters growing red tomatoes that sit on a roof painted white. In my view, this is the best of all worlds.
We should have many more combo green and white roofs than we do. We can thank our laggard horticultural education for that. Thankfully, we have rooftop growers who are sharing their experience on the web about high productivity and water conservation using sub-irrigated planters (SIPs). We just need to get the word out that white and green is better than green alone.
A new study of how different white roofing materials performed “in the field” in New York City over multiple years found that even the least expensive white roof coating reduced peak rooftop temperatures in summer by an average of 43 degrees Fahrenheit. If white roofs were implemented on a wide scale, as the city plans to do, this reduction could cut into the “urban heat island” effect that pumps up nighttime temperatures in the city by as much as 5 to 7 degrees Fahrenheit in the summer, said the study’s lead scientist, Stuart Gaffin of Columbia University. (Credit: © D.aniel / Fotolia)ScienceDaily (Mar. 7, 2012) —
On the hottest day of the New York City summer in 2011, a white roof covering was measured at 42 degrees Fahrenheit cooler than the traditional black roof it was being compared to, according to a study including NASA scientists that details the first scientific results from the city's unprecedented effort to brighten rooftops and reduce its "urban heat island" effect. Read more...