During the day plants extract carbon dioxide, carbon monoxide and many other toxins from the air during photosynthesis, resulting in significant reductions in CO2 levels in well vegetated urban areas.
Benefits of Green Walls
Large areas of greenery help to suppress dust particles; improving air quality around construction sites and busy highways. This may lead to a reduction in respiratory illness. There has been much focus in London recently on reducing PM10 particles to meet EU regulations.
Planted surfaces have low noise reflectivity and high absorption properties. Ambient noise is attenuated by ivy screens and living hoarding, improving conditions for building occupants and pedestrians.
Installing green façades and living walls can result in many benefits to the environment, buildings and human welfare. The list below provides more detail on what benefits can be realised with urban greening solutions in general and how these are achieved.
Health & wellbeing
Plants and greenery can provide uplifting and calming effects on people whilst having a positive impact on stress-related illnesses. Studies have shown that simply having a view of greenery increases workplace productivity and patient recovery rates in hospitals.
Urbanised areas have a higher average temperature than surrounding countryside. Increasing vegetation in city hot spots, or urban canyons, provides canopy cooling of trapped air and reduces reflected heat. Tests have shown temperature differences of up to 17⁰C between hard and vegetated surfaces in the same location.
Vegetated surfaces are generally considered aesthetically pleasing; they can provide a visual impact and focus for onlookers or can be used to obscure unsightly structures and spaces.
By using a broad range of plants a green wall can considerably increase the number and variety of insects and birds in a given area, helping to return a more sustainable ecosystem in urban environments.
Increasing the coverage of vegetation can reduce storm water management for a building. This is especially useful in older urban areas where excess storm water is combined with wastewater systems. More advanced solutions can harvest excess rainwater for green wall irrigation, eliminating the need for a fresh water supply.
The introduction of vertical gardening techniques significantly increases available space for growing food in urban environments.
Green walls are visual indicators of sustainable design and can be a means of qualifying for additional eco-credits for sustainability assessment schemes and may help with planning applications.
Green walls help reduce UV damage to surfaces and can protect a building from wind, weather and temperature fluctuations, prolonging the life of the structure. These factors could offset maintenance costs of green walls.