1. IntroductionThe emergence of highly urbanized landscapes has led to aplethora of environmental problems such as increased stormrunoff, degraded water and air quality, high building energy use,and the urban heat island (UHI) effect. Green building standardsincentivize passive technologies that reduce the energy andenvironmental footprint of structures and mitigate many of these problems. One simple strategyto improve building energy efficiency is to increase roof thermalinsulation. Cool roofs and green roofs are alternative methods thatalso promote the natural reduction of air temperatures duringthe summer months. Cool roofs involve a highly reflective layer