Green Roofs in the Heat: Do They Really Help in Yazd?

In the scorching heat of Yazd, Iran, the idea of green roofs sounds appealing. These roofs, covered in plants, are supposed to make the air cooler and more pleasant. But do they really work in such a hot and dry place? To find out, a detailed study was carried out. The study focused on three types of roofs: intensive green roofs, extensive green roofs, and plain roofs with no plants. The simulation ran from early morning to late afternoon during the hottest time of the year. The goal was to see how these different roofs affect the temperature, humidity, and overall comfort. Intensive green roofs, packed with plants adapted to desert conditions, showed the most promise. They lowered the air temperature and made the surroundings feel cooler. These roofs also increased wind speed and humidity, which can make a big difference in how comfortable a place feels. Extensive green roofs and plain roofs, however, did not show much difference in their effects. Both types had similar impacts on the microclimate and thermal comfort. The study found that intensive green roofs performed best in improving comfort. However, even with these roofs, the conditions were still very hot and uncomfortable during the peak hours of the day. The improvements were most noticeable in the early morning, but as the day went on, the heat became intense. The surrounding environment did not see significant benefits from these green roofs. This raises questions about their practicality in such a harsh climate. Yazd faces extreme heat, intense sunlight, and severe water shortages. These conditions make it challenging for green roofs to be effective. While green roofs aim to improve the microclimate and comfort during hot periods, their benefits in Yazd are limited. The study suggests that building green roofs in such a harsh environment may not be the best idea. The severe conditions of Yazd make it difficult for green roofs to make a real difference. It is crucial to consider the local climate and resources when deciding to implement green roofs.