Building energy regulations worldwide are increasingly advocating for better-insulated facades since improved insulation in facades can significantly reduce a building’s heating energy demand. However, research indicates that super-insulated buildings are already at risk of overheating due to high internal heat storage and low heat loss. In addition, over the past decades, the climatic trend demonstrated a significant rise in surface temperatures. As a result, well-insulated commercial buildings have become increasingly dependent on cooling.
On the other hand, approximately 85% of Europe’s glazing comprises single glazing and uncoated double glazing. This prevalence leads to high demand for heating and cooling energy. Therefore, there is an urgent need to enhance the insulation of these buildings’ glazing while maintaining the existing window frames.
A glass unit prototype with switchable insulation has been developed and assessed to address these issues. The findings of this thesis demonstrate that in mixed climate zones, the utilization of switchable insulation can lead to a reduction in total energy demand by as much as 33% compared to the use of present high-performance glazing technologies.
When advantageous, Inflatable Glazing can be activated on-demand or controlled by internal and external sensors. The heat transfer coefficient of the facade, known as the U-value, can be switched from a low insulating value to a high conducting value. During the cooling period, this technology can be employed to increase the heat flux of the glass unit, thereby enhancing heat dissipation. Conversely, Inflatable Glazing can provide excellent insulation and highly effective solar gain during the heating period.
This thesis investigates the potential of a switchable insulating glass unit for buildings in mixed and mild climate zones, where selecting the appropriate U-value can be complex. The focus is set on building and testing a fully transparent glass unit with a switchable U-value. The innovative material, thin glass, serves as the primary dynamic component due to its advantageous bending properties and strength.