External Insulation Systems for Buildings with Complex Façades in Urban Historic Centers

The European cities, and in particular the Italian ones for their historical nature, have to solve the issue of energy retrofitting of the buildings of their historic centers urgently [1]. The interventions to improve in a passive way the energy performance of buildings are mainly based on controlling the amount of thermal energy that the building exchanges with the environment. These interventions are closely linked to the external microclimatic conditions, which vary over time and space; for this reason, especially in temperate climates, where there are significant seasonal and daily temperature variations, it is important to combine heating and cooling needs. This is achieved through the production, collection, and accumulation of heat inside the building and, at the same time, through the reduction of heat losses to the outside. If the first result can be achieved by maximizing the exploitation of solar energy and increasing the free thermal inputs generated inside the building; the second one can be achieved by improving the thermal insulation of windows and walls.