Temperatures can be reduced by covering a wall with a layer of vegetation that shades building materials which would otherwise absorb heat.
Evapotranspiration provides cooling effects, as water is evaporated from the growing medium and plants transpire by taking water in through roots and releasing it through leaves. Energy from the sun that would otherwise heat the green wall surface and increase ambient air temperatures is instead used in the evapotranspiration process, resulting in latent heat loss that lowers surrounding air temperatures.
Green walls provide aesthetic variation in an environment in which people carry out their daily activities. Green walls can bring people aesthetic enjoyment fro the following aspects:
Plants with a high foliage density trap small particles and also assist in removing particulate pollution.