Strategies to Face Overheating in Industrial Buildings Located in Mediterranean Climate Area

Most of the Italian industrial buildings are outdated, mainly built in the 70s and 80s and characterized by several energy-related issues during both winter and summer seasons. As for the latter, in most industrial facilities a cooling system is not installed. Consequently, the thermal comfort of employees within the working space might be not guaranteed during the hottest days when the peak indoor air temperature can also reach very high values. Moreover, the value of cooling degree days is constantly increasing (19% more with respect to 1979) following the current climate change. The rise in external air temperature negatively affects both the energy performance of buildings and the internal thermal comfort of users. Considering this context, the research aims to evaluate some strategies to be applied to existing industrial buildings to face summer overheating. The measures proposed are related to the external envelope, passive natural ventilation, and lighting system. The different analyzed alternatives are compared through energy simulations in Design Builder by assessing the internal air temperature value, the energy demand for cooling and the overall energy balance through the external envelope. In general, strategies focusing on the enhancement of the external envelope proved to be more effective in reducing summer overheating than the ones related to natural ventilation. The combination of the reduction of the skylight area and the cool roof strategy results in a peak reduction in the internal air temperature equal to 3°C. Considering the occupancy time the reduction in the average indoor air temperature is instead equal to 2.5°C. Natural ventilation in terms of night cooling is particularly effective during the first hours of working time while the installation of LED lighting affects overheating to a lesser extent.