An Empirical Study on the Use of Water Film in Glazed Buildings to Reduce Solar Radiation Transmittance in the Tropics

Solar radiation is the cause of large heat gain in glazed buildings particularly in the tropics, thus the aim of this study is to investigate the impact of a sustainable water film on glazing transmittance to solar radiation. The experimental investigation measured two parameters, namely, type of glazing and solar radiation intensity, utilizing glazed façades oriented west in two full-scale rooms. It was found that the water film on the glazed façade increases the transmittance of solar radiation behind the glazing by 2% - 6.8% depending on the solar intensity and glass type, while the indoor temperature was reduced. The study concluded that the increment of the solar radiation (300–2500nm) transmittance is an increment in the range of the visible light (daylighting).