Vertical urban surfaces and building facades remain a largely untapped resource for green infrastructure as they pose specific installation and maintenance challenges. These challenges are being address by Arup, whose Foresight team have developed design solutions for both permanent and temporary green facades.
Vertical Meadow (formerly known as Living Wall Lite) is an innovative and cost effective living wall system for temporary applications such as construction site scaffolding and hoardings. It has been developed by Arup in partnership with Green Fortune, a living wall provider with a track record of over 300 living walls across Europe. Plants and flowers are grown from seed in-situ on a temporary mat that is easily fixed to any scaffolding or hoarding. Within two or three weeks the first shoots start to appear, before growing into a verdant vertical meadow. The species-rich wildflower meadows that grow are a haven for biodiversity, attracting bees with a high pollen flower mix as well as other insects such as ladybirds and spiders. Wild strawberries also help to produce food for other fauna such as local birds.
Like the trees and parkland in cities, the wall’s aesthetics will change with the seasons. In the spring and summer it will be lush and verdant and in the winter it will brown-off and die back a little, only to bounce back the following spring. This seasonality creates ongoing interest - a dynamic visual impact that constantly evolves.
Rainwater can be channelled through the system, both minimising the mains water irrigation for the plants, and reducing pressure on the mains drainage system. When connected to a re-circulation system water usage can be optimised for the whole system.
There are also positive impacts on local air quality and noise. Plants capture dust and particulates, and release them via precipitation into the drains. This can help to reduce dust and pollution by up to 20%. Studies show that people with views of greenery have a lower perception of noise. Moreover, plants help to attenuate street noise by reducing reverberation, and the wall helps minimise noise breakout from the work. Initial tests show a reduction of 13dB - comparable.
The Vertical Meadow system can be applied as a hoarding or scaffolding wrap. The mat arrives to site in rolls for installation by the site team, with Green Fortune overseeing the process and installing the irrigation system. A broad and adaptable seed mix ensures that each Vertical Meadow thrives in a range of varied site conditions. Basic monitoring and maintenance is quick and simple, and the site team can be trained to carry it out themselves. The system uses materials with low embodied energy, and because plants are grown from seed in-situ, there is none of the energy usage associated with growing plants in greenhouses off-site.
The Vertical Meadow System is currently being deployed by Grosvenor over scaffolding at the St Mark’s building, a Grade I listed property in London.
Arup’s permanent green façade, Living Wall, has been designed in partnership with DesignLaw and utilises similar techniques and has all of the ecosystem benefits provided by the Vertical Meadow. The permanent installation is modular system of aluminium foam tiles, backed with a pre-seeded root mat. Water and nutrients are delivered through a hydroponic systems and the tiles can be attached via a standard façade backing cassette.
It is hoped that these innovative systems developed with Arup and partners will promote greening, increase biodiversity and enhance ecosystem services of our current and future cities.