Survey and restoration of outdoor glass reinforced polyester sculptures

The beginning of the use of polyester resins for artistic work date back to the late 1950s. Initially, resins were supposed to temporarily replace and imitate traditional but more expensive sculptural materials (stone, bronze). Later, original, especially fiberglass works were created, where the laminate formed a shell connected to the internal supporting steel structure. Until now, only part of the exterior works of art made of polyester resins have been survived. Although polyester resins are considered to have good weather resistance, most exterior sculptures exhibit more or less severe defects, often resulting from neglected maintenance. The main types of defects occurring in polyester fiberglass works are presented. The most serious damage is cracks in the entire thickness of the shell, because water can easily penetrate to the internal steel structure. In the case of prolonged water penetration, the statue may collapse due to corrosion. The article presents the procedure of exploring the fiberglass sculpture from the 1950s with the introduction of suitable methods for the documentation of the state of the work. Finally, suitable restoration interventions to maximize the life of the statues are discussed.