Energy and environmental performance assessment of reused PET bottles panels for building thermal insulation solutions

Abstract

The construction industry is responsible for several environmental impacts, such as high consumption of raw materials and energy, significant contributions to global CO2 emissions, and waste production. Furthermore, concerns regarding waste and by-products valorization have been growing recently, particularly for plastic waste, whose integration into building materials components is under investigation. Different applications of polyethylene terephthalate (PET) have emerged, particularly for nonstructural purposes, with potential benefits as thermal insulation solutions, showing that further studies should be conducted for a more detailed analysis and characterization of this type of building solutions. In this context, the current study contributes to the thermal and environmental performance characterization of alternative materials composed of PET bottle panels filled with soil, water, and air. An experimental evaluation of the thermal performance and a Life Cycle Assessment (LCA) were conducted considering the horizontal and vertical positions of the bottle panels. The lowest values of the thermal transmission coefficient were observed for the PET bottles filled with soil, achieving 0.46 W/m2°C for the vertical position. Regarding LCA, the panel with empty bottles showed the best environmental performance, which was justified by the fact that no filling process was considered. Considering that filling bottles with air or soil results in similar environmental impacts, it can be concluded that PET bottles filled with soil provide the best thermal and environmental alternative.