Trees on roofs and facades can have a cooling effect on the temperature of the building and the surrounding environment. This is because trees provide shade and transpire water, which helps to reduce the amount of solar radiation that is absorbed by the building's surface and the air around it.
In addition, trees can absorb carbon dioxide and other pollutants from the air, improving the air quality and reducing the amount of heat-trapping greenhouse gases in the atmosphere. This can have a positive impact on the urban heat island effect, which is the phenomenon where cities are significantly warmer than surrounding rural areas due to the concentration of heat-absorbing surfaces like pavement and buildings.
The specific impact of trees on temperature will depend on various factors such as the species and size of the trees, the location and orientation of the building, and the climate and weather conditions in the area. However, in general, trees on roofs and facades can help to mitigate the urban heat island effect and reduce energy consumption by providing natural shade and cooling.