I keep reading that to lower the urban heat island effect (UHI), architects should use green roofs or light color painted roofs. This isn't the same as saying use high albedo materials, which I've also read, because vegetation doesn't have high albedo. I've also read the materials should be high in albedo and have a minimum reflectance of 0.3, but having a highly reflective material will also increase UHI - see question 17 which I answered C because of this confusion but they say D.
So in reality to lower the urban heat island effect the roof should be either a green roof, which is low in albedo and low in conductivity, or light/reflective painted, which is high in albedo and high in conductivity but not too reflective or mirror like because it will heat up adjacent taller buildings... Seems pretty confusing unless I'm missing something.
This leads back to my previous PPP question about how to moderate the microclimate on a site, which means the same thing as reducing UHI right? : viewtopic.php?f=4&t=52570&start=40 - posted at Wed Mar 21, 2018 7:30 pm.