A COMPARATIVE STUDY OF RETRO-REFLECTIVE FILM IN THE TROPICS

Abstract

Retro-Reflecting Film (RRF) is a new revolutionary product which benefits includes mitigation of UHI effect and enhancement of outdoor thermal comfort, while improving the energy-saving performance and comfort of the indoor environment within the built environment. The study of the performance of RRF was conducted by Inoue et al. (2013), and result from his study has confirmed that the product functions effectively in temperate conditions. However, thus far, no study has been done to determine if the benefits of RRF could be experienced in the tropical climate. A comparative study is proposed to determine the effectiveness of RRF in the tropics. The film is incorporated into a clear glass (RRFG), and this specimen is benchmarked against two other glass types, Clear Glass and Privacy Glass. Initially, a laboratory spectrophotometric study is conducted to have a preliminary understanding on the characteristics of the three glass specimens. Subsequently, a comparative field study is conducted to study the characteristics of RRFG in the tropical climate. From the preliminary study, there is indication that the RRFG has the best ‘balance’ in daylight-thermal trade-offs relatively. Moreover, according to the field study, the result shows that RRFG does have a comparative positive impact on the UHI effect in Singapore. Further, there is also indication that RRFG does provide better outdoor thermal comfort as compared to Privacy Glass. Finally, though a Sun-path simulation study, the most effective period for the RRFG in alleviating the UHI effect is determined to be from 15:40hrs to 16:00hrs, when the Sun’s angle and position is approximately 51° to 45°, to the West of Singapore.