Climatic Loads on Triple-Glazed Insulating Glass Units Used as an External Horizontal Building Envelope

Insulating glass units (IGUs) have tight cavities filled with gas in their structure, which results in a specific manner of transferring climatic loads. Under the influence of these loads, the gas in the cavities changes its parameters, which affects the resultant load on each of the glass panes in the unit. In the computational models described in the literature concerning this phenomenon, vertical location of IGUs is usually assumed. However, nowadays glass roof-ceilings and rooflights with triple-glazed IGUs located diagonally or horizontally are more and more often implemented. In this case, an additional factor influencing the static quantities in IGUs is the own weight of glass. The aim of the article is to analyze the influence of the horizontal location of triple-glazed IGUs on their deflection and stress under climatic load. The analysis was carried out using own analytical model. Based on the presented examples, conclusions were drawn about the resultant loading, deflection and stress in IGUs of various structure and dimensions with climatic factors. It was shown that extreme annual temperature changes and a large increase in atmospheric pressure are the most dangerous in the context of the possibility of excessive deflections. The horizontal location, on the other hand, mitigates the effects of atmospheric pressure drop and wind suction.