Increased thermal induced climatic load in insulated glass units

Abstract

In the mid-1990s the climatic loading of double-glazed units (DGU's) was investigated and design rules were developed for use in practice. Even though at the time those rules were developed for DGU's, they have recently also been used for the design of modern triple-glazed units (TGU's) and multilayer facade systems. So far, no research has addressed the question whether this design process, and in particular the temperature differences that have been determined for DGU's, can be applied to other systems. It is therefore the aim of this paper to determine the governing temperatures in insulated glass units (IGU's) under up-to-date boundary conditions. To do this, the thermal behaviour of TGU's, multilayer facade systems and solar shading is investigated in detail. A simple calculation model is developed, which can be used to determine the gas temperatures in various facade configurations in accordance with the relevant standards. The results show that while parts of the existing requirements are still valid, there are distinct differences in the requirements for more contemporary applications. The gas temperatures affect the climatic load and therefore also influence the structural design of IGU's.