Stating the necessity of increasing the designers’ awareness of both lightweight and flexible materials and their performances, in a life cycle thinking perspective, this contribute is based on the updated identified needs of the membrane sector (Cost Action TU1303, 2017): Life Cycle Assessment, durability aspects, recyclability, social acceptability, thermal, optical, acoustic comforts. Into the frame of the Tensinet association activity, the Textile Architecture Network of Politecnico di Milano is continuing the search of Eco-design strategies and enlarging the mapping of case studies, by the application ex-post of two eco-efficiency principles in order to verify their validness and their efficacy for the designer’s need, during the desig...