Understanding the performance of vertical gardens by using building simulation and its influences on urban landscape

Urban development can have a profound impact on the health and well-being of people, sustainability of cities, increasing energy consumption because of increasing urban heat island (UHI), and CO2 which is one of the environmental and social concerns. The vertical garden as a second skin on the façade has been analyzed in this paper, are compared using several constructive alternatives in a natural and sustainable way. The main proposal of this study is a second skin (green façade) in an office building in Barcelona, Spain, that is in southwest orientation, which aims to reduce energy consumption as much as possible and improve the urban landscape, and pedestrian comfort. Vertical gardens as a second skin are implemented on the building's exterior walls to intercept a quantity of solar radiation towards the vertical building envelope. The methodology is based on the evaluation of various green facade options through simulation of the different sizes of the cavity's depth with a specific orientation. According to the result of the simulation obtained from Autodesk Green Building Studio, the cavity's depth, and the density of plants (R-Value) are very effective in the performance of the green facade which must be calculated as specified by the building main facade's material and structure, building orientation, the height of the building, and climate. This paper presents a case study that applies this approach in an office building located in Passeig de Gràcia, L'Eixample area in Barcelona.