Composite materials for renovation of roofs in existing buildings

The EPBD directive (91/2002/EU) paved the way for the European Union member states to develop and apply a holistic approach on the building’s energy performance. It is documented that buildings’ energy consumption represents 40% of the total energy consumption in Europe, a significant figure when compared to the industry and transportation sector. Respectively the CO2 emissions are calculated to be around 30%.  A series of published data indicates that the uninsulated or poorly insulated roofs account for up to 25% of energy losses. Taking into consideration the significant downturn of new constructions monitored all over Europe after 2008, energy refurbishment of the existing building stock appears as a nodal point towards the mitigation of the energy consumption.  
In particular for retrofitting insulation solutions for the roof we need to apply insulation with regard of the technical parameters of the roof. Thus, a combination of a board of extruded polystyrene with a ceramic tile would provide effective thermal protection. Moreover, a material like this can be characterized as cool material because of its light colour and the high reflectance. Application of this kind of material in existing roofs in Greek buildings indicated a reduction on the energy consumption and an amelioration of the temperature of the apartment below the roof. 
In this paper, the results of the application of the composite material are presented along with its technical characteristics.