Hot-box tests for building envelope condensation assessment

A common architectural feature of curtain wall facades is constituted by a transparent double-glazing unit mounted in front of a recessed interior metal panel. It is typically installed in spandrel areas, where its required to provide to the faade not only surface consistency but also depth.To evaluate condensation risk on this type of envelope element, an experimental program has being carried out on a typical facade panel (Shadow-box) provided by Permasteelisa. The specimen performances were investigated using a guarded hot-box and an extensive 3-dimensional temperature monitoring has been carried out under various steady-state winter conditions. The temperature on the glazing and surrounding frames has been compared to the dew-point temperatures. Particular emphasis has been given to the pressure equalization between the outdoor environment and the inner space of shadow-box. Moreover the applicability of the temperature factor, proposed in European Standards, is also investigated as condensation risk indicator on wallinternal surface.