Study on Environmental Control Methods of the Anterior Room During the Limited Opening to the Public of Burnt Wall Paintings in the Main Hall of the Treasure House at Horyu-ji Temple

The Main Hall of Horyuji Temple was damaged by fire in 1949, not only in the building but also in the preserved wall paintings. The wall paintings that survived the fire damage are national important cultural properties and, because of concerns about deterioration, are stored together with the burnt parts in a non-air-conditioned treasure house in the precincts of the temple, which is not open to the public at present as a general rule. In the previous report, a research study was initiated to open the treasure house to the public, and the effects of heat and humidity on the stored items have been studied through annual temperature and humidity measurements and numerical simulations. Based on these findings, an anterior room was constructed in the treasure house and a heat pump desiccant dehumidifier was installed as a dehumidifier to reduce the effects of the outside air and prevent the introduction of moisture into the treasure house. This study reports the control performance of the anterior room and discusses future issues, with the aim of identifying appropriate environmental control measures and operational strategies for the anterior room during periods of limited opening to the public.