Glass is one of the oldest artificial building materials. Recent developments and research works in the last decades made glass to one of the most advanced building materials. Glass is playing a central role in the energy performances of a building. Since ever architects are using glass also for design reasons to give the building an individual look. Renovating a building to improve its performance is often done at the expense of the building’s identity. The aesthetics of the building cannot be preserved because standard solutions cannot offer the same look as old products. This paper should show how to preserve the aesthetics of the building while drastically improving its energy performances by using customized coated glass.