Optimisation of Building Green Performances Using Vertical Greening Systems: A Case Study in Changzhou, China

The benefits of greening systems on buildings have been frequently examined using experimental methods. However, few studies have adopted dynamic monitoring of real operational buildings to quantify the effects of greening systems on multiple building green performance indexes, such as thermal comfort, indoor air quality, and energy consumption. In this study, a type of multi-in-one indoor environmental quality monitoring device was adopted for vertical greening systems in a green-certified building in Changzhou, China, with real-time data collection through an Internet of Things platform. Measurements of the indoor thermal environment and air quality were recorded from four testing points during a 90 day period from spring to summer in 2021. For comparison, the testing points were divided into group A (office zone) and group B (exhibition zone). Our results demonstrated that, in the presence of a vertical greening system, the seasonal average indoor temperatures decreased by up to 0.7 °C. The green facade outperformed the ordinary exterior wall, optimising both indoor thermal comfort and thermal inertia. Furthermore, judicious indoor greening designs significantly reduced the indoor air-pollutant concentrations, such as particulate matter, carbon dioxide, and organic pollutants. The median values for particulate matter 10 and formaldehyde concentration decreased by 20.7% and 33.3%, respectively, thus improving the indoor air quality. Lastly, the annual electricity consumption of the building with vertical greening systems was about 25% lower than that of similar buildings, underlining the potential contribution of vertical greening systems to building energy conservation. Such findings collectively demonstrate that greening systems offer quantifiable benefits for building parameters such as thermal properties, indoor air quality, and energy conservation.