The Supergreen Workplace is a prototype working environment designed to net-zero carbon standards, minimising energy use while providing improved quality internal spaces designed according to biophilic design principles. It features an optimised passive natural ventilation strategy combined with extensive external and internal planting used to naturally control air quality and enhance users’ well-being by increasing connection with nature. Although this particular building is finely tuned to its specific site conditions and climate, it is a prototype where the design principles can be easily applied to many different urban sites or climates.

As well as further reducing the urban heat island effect, providing reduced rainwater discharge and increasing biodiversity, green facades can significantly improve air quality which is very important for a successful natural ventilation strategy. Planting can result in significant local reductions in the concentration of airborne particulate matter both when the plants are internal and when external on green facades.

There is extensive research into the use of plants to improve indoor air quality and maintain a healthy indoor eco-system, but recent studies have also shown how the use of green facades can result in significant local reductions in external concentrations of particulate matter as the leaf surfaces of plants capture and remove particles from the atmosphere. Green facades are most effective when planted over the whole height of the building using planting with a high density of leaves. Vegetation on the lower storeys is effective in removing locally generated pollution eg from traffic and can clean air prior to it entering the building. High-level façade planting is most effective at removing wind-driven pollution generated from further away and helps combat the ‘street canyon’ concentrating effect which can be exacerbated by tree canopies. The vegetation is specified to relate to the orientation of each elevation and extensive internal planting is also used to provide internal humidification and improve general well-being.