Further causes of collapse under heavy snow loads
In the January 2026 issue of the Dutch journal De Ingenieur, Rob Nijsse, emeritus professor of structural design, identifies snow load as a major factor in the collapse of roofs and other structures. He also mentions other possible causes, such as local snow drifts and the extra load from building services and solar panels.
What is striking, however, is what this analysis leaves out: the role of thermal stresses. At low temperatures, construction materials contract, but in practice this natural movement is often restrained by detailing, fixings or later alterations. The result is internal stresses that can build up invisibly.
Particularly in combination with heavy snow loads, such thermal stresses can significantly reduce safety margins and so increase the risk of collapse. That makes them not a theoretical detail but a real risk that should be explicitly considered in the design, assessment and management of structures – especially now that roofs are increasingly covered with additional equipment.