Comparative assessment of roof tiles’ environmental performance from cradle to cradle

Abstract

Roof plays an important protective role in a building, and claddings are the first element to collaborate in that function. In Portuguese architecture, ceramic roof tiles are the most common claddings in pitched roofs. Concrete roof tiles are a good alternative because of their technical performance and visual similarity to ceramic ones. Both have been studied in different perspectives, but there is no updated comparison of their environmental performance in the European context. For this research work, the environmental performance of ceramic and concrete roof tiles was studied and compared, based on the Life Cycle Assessment (LCA) methodology and following international standards. A cradle-to-gate LCA was performed for the product stage of concrete roof tiles. The LCA approach applied in the comparison study was cradle-to-cradle, based on plausible and conservative scenarios. They are presented for the product stage for the respective reference flows, based on the LCA performed for concrete roof tiles within this research work, and in another recent LCA performed for ceramic roof tiles in Portugal. A comparison is then performed between the LCA results from cradle to cradle of ceramic and concrete roof tiles when applied in a building for a service life of 50 years. Ceramic roof tiles present lower environmental impacts over their life cycle in five out of seven impact categories: ADP-Elem. (different magnitude), GWP (-16%), POCP (-10%), AP (-5%) and EP (-89%). The exceptions are ADP-ff and ODP for which concrete roof tiles present a better environmental performance (-44% and -64%, respectively). For both roof tiles, it was concluded that the production stage is the most relevant, representing between 63% and 84% of life cycle impacts.