Life cycle sustainability assessment of window renovations in schools against noise pollution in tropical climates

Because of the significant increase in the number of noise complaints, reducing and limiting noise pollution have become prevalent subjects related to the retrofitting of school buildings. The present case study considers a multi-apartment school building in the city of Johor, Malaysia. The life cycle criteria evaluated in this study are carbon dioxide (CO2) emissions and the cost and social impacts of each window type. The preliminary assessment showed that the school's current noise level is 74.31 dB (A), which exceeds the acceptable threshold of 55 dB (A). In the next step, three more windows were applied and reevaluated, with the triple glazing window performing the best (48.66 dB (A)), followed by the double glazing window (51.3 dB (A)). In terms of carbon emissions and cost, the preference window had the best performance. Meanwhile, considering the social aspect, the double glazing window performed the best. Because three different windows were deemed the best choice depending on which of the four criteria was considered, multi-criteria decision making (MCDM) was applied by TOPSIS to weigh and estimate each alternative. The final decision was made by giving priority to the four criteria as follows: noise (0.322), cost (0.257), CO2 emissions (0.227), and SLCA (0.194). The MCDM process revealed that the double glazing window is the most sustainable choice for school buildings. Furthermore, two sensitivity analyses were performed to eliminate human subjectivity involved in AHP.