Wind Load Assessment of Unitized Double Skin Facades

Load sharing in multiple skin facades depends on several parameters, main of which are the geometry of the units and the permeabilities and stiffnesses of the skins. Experimental and numerical tools exist, which are commonly adopted by the industry in the design and testing of specific products. Code specifications are also available, facing the difficulty of covering a quite broad range of solutions, whose physical behaviour may differ substantially. In this paper, the evolution of Eurocode specification concerning the wind loading of multiple skin facades and roofs is first traced, from ENV 1991–2-4:1995 to the current proposed update prEN 1991–1-4:2020. Then, the mechanism of static and dynamic pressure propagation into the cavity is illustrated, for the case of double skin facades and roofs; a possible approach for future Code development is shown. Finally, the results of numerical simulations and experimental tests are compared for the particular case of unitized double skin facades.