This thesis seeks to assess the environmental impact of two design proposals for a residential project using LCA methodology through the Oneclick LCA tool with BIM integration. The core of the thesis is to optimize a business-as-usual scenario which is a residential project designed by Officina8A Architetti e Associati in Turin, Italy, with the intent of demonstrating how building structure and materials decisions influence global warming potential (GWP). With a background about LCA approach and local material investigation in the area of Turin, the study assess the global warming potential (GWP) between a reference business-as-usual (BAU) scenario and its optimizated version using low-carbon materials locally available.