Critical exposure time for panel paintings due to change in environmental conditions

Balancing the preservation of historical collections with energy consumption related to climate control is vital in museums and historical buildings to reduce carbon footprints. This is especially important for the structural integrity of hygroscopic objects like panel paintings, which are susceptible to damage from environmental changes. To address these challenges, a Finite Element (FE) hygro-mechanical-uncoupled model has been developed to assess the safety of panel paintings under changing environmental conditions, specifically changes in relative humidity (RH%) at a constant temperature (T). The model, similar to a thermal problem, uses material parameters from literature expressed consistently with RH as the driving potential. It evaluates scenarios involving panel paintings with different wood supports (Pine and Poplar) subjected to abrupt environmental changes, with or without moisture exchange through the gesso layer. This simulation approach investigates the environmental effects and their temporal evolution on panel paintings. The main outcome is the evaluation of the critical exposure time for a panel painting to experience new damage, particularly in the gesso layer, due to internal cracks.