Green façades and in situ measurements of outdoor building thermal behaviour

Abstract

Using green façades in large cities with hot climates has been introduced in the search for more sustainable solutions for urban development. This paper presents the data collected in situ and quantifies the thermal external behaviour of a green wall and a bare one in the same surrounding environment in the city centre of Madrid, Spain. The methodological approach helps to assess the impacts of both walls on the variation of the urban temperature range at the microclimate scale in accordance with environmental physical data at different seasons and times of the day. In the summer campaign, the maximum values of air temperature reduction as measured in situ range between 2.5 C and 2.9 C which confirmed the values of various other studies using similar measurements. In the autumn campaign, the maximum values were half of the ones obtained for the summer, not exceeding 1.5 C. However, these values increased after calculating similar conditions of sunlight in both façades. This comparative analysis of the experimental results on a green wall and a bare wall demonstrates that green façades can have a significant temperature reduction potential in the surrounding microclimate.

Living walls in indoor environments

“…The studies ranging from observational studies to modelling simulations suggest that the immediate air temperature modifications of vertical greening including direct, indirect, or living wall approaches to range between 0 and 3 K at most, while the effective range seldom exceeds 1 m from the wall surface [e.g. 8, [11][12][13][14][15][16]. Higher performance has been demonstrated when conditions are drier and warmer (summer), relative to colder (autumn and winter) conditions [e.g.…”

Progress in Urban Greenery Mitigation Science – Assessment Methodologies Advanced Technologies and Impact on Cities

“…Vertical greening, also referred to as green wall or facade greening, is likewise helping cities adapt to climate change by reducing air and facade surface temperatures and peak energy demand (Cheng et al 2010;De Jesus et al 2017;Kalani et al 2016). However, location, placement, and plant configuration determine their effectiveness in terms of surface and air temperature reduction and energy saving.…”

Green Façade Effects on Thermal Environment in Transitional Space: Field Measurement Studies and Computational Fluid Dynamics Simulations

“…Perini et al found that the average temperature of the air cavity, inner leaf, and 0.1 m in front of a GF was reduced by 0.34 • C, 0.17 • C, and 0.13 • C, respectively, compared to the point in front of a bare wall, and there was no difference found at a distance higher than 1.0 m in front of the GF [17]. De Jesus et al investigated two LWSs in situ and found a maximum outdoor temperature difference of 1.5 • C compared at distances of 0.5 and 4.5 m [3]. Koyama et al showed that room temperature was reduced by 0.15 • C and 4.0 • C due to transpiration and shading cooling effects, respectively [18].…”

“…In response to the lack of land in some densely built-up areas, the vertical green strategy has been introduced to provide more green space and dissipate the thermal stress under the extreme artificial environment. As one of the vertical greenery systems (VGSs), the application of green walls (GWs) has the potential to optimize the energy consumption of buildings [2] and increase outdoor thermal comfort [3].…”