Nanotech materials for the maintenance of the outer surfaces

The outer surfaces of built environments have a key role in the perception of their aesthetic value as well as in the protection from aggressions of external environment. For these reasons, they are the skin of the construction and they should be preserved through maintenance works. The choice of materials to be used for their preservation depends on the forms of degradation that characterize the environment in which the construction is located. In this paper, we propose the use of a nanotechnology material based on lime and graphene for the restoration of the external surfaces of the Opera Palace of the monumental complex called "City of Sciences and Arts"of Valencia (Spain). The palace, built in the early years of the millennium on a peripheral area and degraded the city along the ancient bed of the river Turia, has a complex geometry that reminds of the shape of a boat oriented along the direction of the old river flow. The curved outer surfaces are made of steel coated with a ceramic mosaic of white color put in place according to the trencadís technique. The high temperatures of the city’s weather and the different behavior to the thermal expansion of the two materials in direct contact each other caused the detachment of trencadís by the metal surfaces, which seriously compromised the aesthetic and functional usability of the building.