Vertical Greenery Systems as a Strategy in Urban Heat Island Mitigation

Abstract

Integrating vegetation into architecture has become widely recognized as a multi-beneficial practice in architecture and engineering design to combat an array of environmental issues. Urban areas have microclimates that are different than the climates of their surrounding rural areas. Patterns in these differences over the years have shown that urban microclimates tend to be significantly warmer in comparison. This phenomenon is now recognized as the urban Bheat island^effect. While the associated consequences of this urban heating are far reaching, excess energy expenditure, air pollution emissions, and threats to human health are among the most critical for evaluation. The integration of vegetative green space in urban planning, coupled with highly reflective materials in place of conventional paved surfaces on roads and rooftops have proven to be effective methods of urban heat island mitigation. While as separate entities these methods are effective, innovative technology has brought forth greening roofs which allows vegetation to compensate where other roof-cooling strategies fall short. Substantially, vertical greenery systems compensate where greening roofs fall short. This paper explores both integrated vegetation as an optimal mitigation strategy for urban heat islands and vertical plant walls as an optimal design.

A novel vertical greenery module system for building envelopes: The results and outcomes of a multidisciplinary research project

“…This kind of technological solution is able to provide different beneficial effects: during the cooling season, thanks to the shading effect of the leaves and the evapotranspiration of the plants, the entering loads are lowered [10], while, during the heating season, it can contribute to reducing heat losses and improving surface thermal resistance, because of the wind reduction in the vicinity of the wall [11,12], to increasing the sound insulation of the wall [13,14] and reducing the environmental impact of the buildings [15][16][17]. At an urban level, VGSs are able to filter pollution [18], to sequester CO2 [19], to reduce urban sound propagation [20][21][22], to give a pleasant aesthetical aspect to a building, to improve the bio-diversity [23] and to mitigate the urban heat island effect (UHI) [24,25]. The species used in outdoor living walls vary to a great extent, depending on the location, on the exposure to the sun and wind and on the height of the building [26].…”

The Inclusion of Natural Elements in Building Design: the Role of Green Rating Systems

“…This phenomenon, recognized as the urban heat island effect, can be mitigated by green areas on land, green roof and green in façade [14].…”

Spatial characteristics of open park spaces and perceived warmness in a tropical city

“…According to [25], parks incorporated with greeneries provide higher levels of thermal comfort, with approximately 0.94 °C of reduced daytime temperatures. It should be noted that existing literature on the potential of parks to combat urban heat mainly centered on urban parks [26], urban gardens [27], green roofs [28], vertical greenery [29], urban trees [30] and pocket parks [31] in accordance with the size and shape. Nonetheless, the potential of OPS as a viable mean for UHI reduction is still subjected to further investigation in the tropical context.…”