ZEMCH 2015 - International Conference Proceedings | Page 863

High definition infra-red images are used as tool for collecting complete data on the wall and on
the leaf surface temperatures (Cameron et al. 2014; Köhler 2008; Theodosiou 2009). Thermal images were recorded for each wall using a thermal infrared camera (mod. B660, FLIR Systems, Burlington, ON, Canada) in order to analyze the surface temperature of the plants and to validate the
surface temperature of the walls measured using the above mentioned thermistors. The camera
was calibrated to an average value of emissivity of 0.95 for both Pandorea jasminoides variegated
and Rhyncospermum jasminoides; the emissivity value set for the white plaster covering the walls
was of 0.96. The average temperature of the leaf surface and of the external plaster of the green
walls were determined by considering the arithmetic mean of a random sample constituted by 20
temperature data points corresponding respectively to the leaves and to the rear back wall (Fig.
3). The average temperature of the external plaster exposed to the solar radiation for the control
wall was determined considering the arithmetic mean of a selected area of points in the thermographic image (Fig. 4).

Figure 3 - Infrared temperature measurement done on the green facade with Pandorea jasminoides
in the mid morning hours in April 2015.

Green walls for a sustainable control of building microclimate

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