G.4.1 – Thermal Fracture in Glass

This article has been written by one of our Façade Engineers, following an investigation on some of the cracked glass panes of the insulated-glazed unit (IGU) of a rooflight/skylight installed on a 3-storey building. Due to the health and safety reasons, the building occupier had replaced the failed glazing units prior to an investigation. However, this investigation was carried out for documentation purposes as well as to prevent from future failures. Although the failed IGU’s were not available to review during the visit of our engineer, the probable causes of the glass breakage, failure mode and recommended prevention strategies to mitigate the risk of future failures are discussed in detail within this article.