Investigation the Role of Green Roof and Walls in the Thermal Performance of Urban Buildings based on Sustainable Architecture (A Case Study in Mashhad-Iran)

Today, in all over the world, due to the problems such as excessive consumption of fossil energy, global warming, climate pollution and major environmental problems, the use of sustainable architecture technologies especially green buildings is important. One of the solutions to bring green spaces in to the buildings is the use of gardens and green walls. The development of green space in roofs, terraces and urban facades improves the performance of green spaces on the regional and urban scale. The building shell is one of the factors that has a significant effect on the energy consumption of buildings and thermal comfort. Creating green walls on the building shell due to insulation, shading and cooling caused by plants' evaporation has a significant impact on energy demand reduction in warm and cold seasons and air conditioning. In the present study, the effect of plant use on roofs and walls, in different views of the building, has been investigated for estimating energy consumption reduction. The results show that by creating green spaces on the roof and walls of the building, the energy consumption decreases. The reduction of energy consumption through the roof is equal to 26/6% and through the south, east, west and north walls, is equal to 6/9%, 8.8%, 8.8% and 6.6%, respectively. Also, the average annual temperature of these levels dropped around 5 °c