Comparison of environmental impact of similar prefabricated industrial structures made of precast concrete or steel

Environmental sustainability is assuming a growing role in the strategic plans of several countries worldwide. In order to switch to more sustainable solutions in the construction field, many researchers and efforts are focusing on the material level, mainly concerning solutions aimed at partially or fully replacing the most impacting components with alternative or recycled solutions characterised by a lower carbon footprint or a higher durability, in view of a life-cycle assessment. Alongside these positive efforts, another instrument to reduce the environmental impact of construction materials, often less tackled by researchers, is reduction of environmental impact by smart structural design. This concept is analysed in the present paper by comparing the environmental impact of similar single-storey supermarket industrial facilities, designed under the same conditions though with different prefabrication technologies: precast concrete and steel. Having at disposal the global bill of materials employed for the superstructure of the precast concrete buildings without cladding and finishes, and after simulated design of a similar steel carpentry building under the same geometric and load conditions, the comparison was carried out based on several environmental impact indicators certified by material producers through Environmental Product Declarations (EPDs). The results allow to evaluate and compare the impact of the structural solutions in the stages of material supply and manufacturing (A1-A3). The analysis demonstrates that, despite using materials with high footprint, the precast solution allows a relevant global reduction of all the environmental indicators, thanks to the structural optimisation allowed by the use of such materials in combination with advanced batching and moulding technologies, and the steel solution turns out being significantly more impacting