Green walls and roof gardens play a far greater part in improving city living than previously thought, according to a new research study.
Improving City Living
Researchers looked at five cities – Berlin, Hong Kong, Melbourne, London and Los Angeles – and measured the impact on noise, pollution and heat of green infrastructure such as vertical planting and green roofs.
They found greenery on buildings can reduce air pollution by up to 20%. Sound levels were also decreased by up to 10 decibels – effectively making traffic sound half as loud.
The study, carried out by design consultants Arup, also found that increasing greenery in a city can reduce temperatures. The ‘heat island’ effect in urban areas can send temperatures soaring by about 12°C above surrounding countryside, but increasing the number of trees and gardens can reduce that to just 2°C higher than temperatures outside the city. Cladding a building in greenery also slashes the amount of energy it uses by up to 8%.
The Benefits of Urban Gardening
‘Tackling rising air pollution is a priority to help improve people’s health,’ said Arup’s landscape architecture leader Tom Armour. ‘As our cities continue to become built up, ‘grey’ structures such as walls and roofs are a source of untapped potential for adapting into green spaces.’