The Energy Upgrading of Existing Buildings: Window and Shading Device Typologies for Energy Efficiency Refurbishment

Residential buildings built after the Second World War have high energy consumption and inadequate thermal comfort, especially in summer conditions, largely attributable to the high transmittance of windows and lack of effective shading devices. Performance improvement of these components is essential for energy upgrading of existing buildings. This paper shows the results of the research, which aims to evaluate effects on energy consumption and environmental comfort of combined solutions of windows and shading devices applied to a case study representing a typical post World War II Italian building. In this paper, the main typologies of solar control systems are described and evaluated on the basis of a case study in different climatic locations (Berlin, Milan, Florence and Athens). Thermal behavior has been assessed through the EnergyPlus dynamic calculation code, by using appropriate performance indicators for energy and thermal sensation. Starting from performance evaluation of the existing building, different strategies have been assessed: replacement of existing windows with high-energy performance ones and introduction of shading devices and solar control glasses. Finally, a global comparative analysis has been carried out based on energy, acoustic and lighting performances, technical feasibility and management problems. Results of the different solar shading devices assessment are reported in the form of a data sheet.