Air temperatures during (a) coolest 5-day period (DOY 100–105) and (b) warmest 5-day period (DOY 145–150) illustrate the range of temperature conditions forgreen roof simulations. The difference between air and surface temperatures (T = Tsurf− Tair) for the different roof types during the coolest period (c) and the warmest period(d) show heating of the traditional roof surface, cooling of the cool roof surface, and maintenance of green roof temperature close to air temperature. The difference betweenroof bottom temperature and desired interior temperature of 21◦C (T = Tb− 21) for the coolest (e) period shows that traditional roofs require cooling during the day andheating at night, and cool roofs always require heating. During the warmest period (f), the traditional roof is always warmer than desired indoor temperature.