Simulation-based performance comparison of façade constructions: vacuum glazing versus common insulation glass

The incorporation of vacuum glazing (VG) products in different window and facade constructions is becoming more viable. The characteristics of the VG products can be summarized as follows: (i) Due to the reduction of conductive and convective heat transfer mechanisms, VG products provide high thermal insulation; (ii) VG products feature low weight and small thickness in comparison to commonly used double and triple-glazing products; (iii) VG is constituted by two parallel glass panes, which are sealed by an airtight edge seal; (iv) The interstitial space between the panes is evacuated; (v) To maintain the parallel positioning of the glass panes, distance pillars are situated within the interstitial space. These characteristics must be taken into consideration when contemplating window and facade construction paradigms that employ VG products. This contribution compares commonly used glass facade constructions (generic post-and-beam constructions with – non-operable – fixed glazing) utilizing insulation glazing with respective facade variations that incorporate VGproducts. Thereby, in a first step, the thermal performance of default facade constructions (equipped with double or triple-glazing) was assessed via numeric thermal bridge simulation. Subsequently, we replaced the insulation glass with a VG product. Thereby the load-bearing post-and-beam details were kept essentially the same. Finally, we slightly modified the facade constructions based on the necessities of VG integration. In this contribution we present the construction paradigms for VG-based facades, the adopted methodology, and the main results of the investigations.