Since no other company except ALUMIL (with an even better proposal of Uw = 0,55 W/m2K), failed to present a proposal in accordance with these standards, the architectural office raised the thermal insulation coefficient to Uw = 1,14 W/m2K, so as to receive more offers. ALUMIL, which operates in the US for a decade now, presented quickly its second proposal, based on the new requirements. Moreover, ALUMIL proceeded also to the construction of a prototype, which included additional external shading blinds with aerodynamic design and internal high functionality shading curtains. The casement window was installed in the agreed time for evaluation, with ALUMIL responding critically faster than its competitors. For the confirmation of the final design, performance tests took place in the advanced testing chambers of ALUMIL in Greece and later on in the US, with measurements in air tightness, water tightness, wind pressure and finally load resistance. Specifically, the innovative R&D department of the company developed a customized version of the outstanding window system SUPREME S91.