Aluminium Alloy Roofing Systems for Sustainable Architecture

The present paper intends to advice readers about the potentialities of aluminium roofing systems in terms of general sustainability, recyclability, and achievement of energy requirements. The use of metal sheet panels for buildings roofing and cladding has been progressively increasing since the very beginning of the last century. Nowadays, several different products are available on the market, either basic or even highly engineered, in different materials, shapes, colours and, of course, prices. Among these, aluminium alloy systems play a major role thanks to the material’s inherent characteristics. For what concerns sustainability, aluminium production allows to use high contents of recycled material resulting in a reduction even over the 95% of the energy required in the process compared to the bauxite ore extraction and raw metal production. The total and theoretical infinite and degradation-less reciclability of aluminium when compared to other metals used in the roofing systems industry makes it easily preferable overall. Such solutions can either concern new roofs covering or refurbishment of existing ones. In the latter case, lots of construction waste is usually generated and eventually ends up in landfills. Instead, aluminium alloy roofing systems allow to be fully recycled and reused at the end of the service life, which is already longer than other non-metallic products, eventually reducing waste transferred to landfills. In fact, the higher cost of such material is largely compensated by its service life expectancy, which is among the longest lasting roofing materials and can reach up, in certain conditions, even to a hundred years. For this reason, complete replacement interventions are still quite uncommon, which favourably contributes on the final environmental impact of the roofing system. In this respect, aluminium alloy systems are particularly suitable, especially when compared with other different solutions, towards design for reciclability. Furthermore, aluminium systems are also indicated for rainwater harvesting purposes, as their surface retains less pollutants than other traditional porous materials and is less likely to give place to mold or concentrated collection of polluting particulates.