Common Problems

This post describes some common issues that may arise in paintings and treatment approaches that may be used to correct them.

Flaking, Cleavage, Tenting, Powdering, Interlayer Separation, Bond Failure

These are all terms that describe loss of cohesion or adhesion that may lead to paint loss. The nature and cause must be determined by the conservator in order to effectively address the problem through consolidation treatment. Typically the paint is softened (usually with moisture) before a consolidant is carefully introduced at the correct interface.

Detail showing severe interlayer separation on a polychrome sculpture.


Not all cracks are created equal, or rather, not all cracks look the same because the mechanism of their formation varies. Different types of cracks include “alligator” or traction cracks, cracks due to impact or pressure (spiral, concentric, feather), ageing cracks (craquelure), “cupped” cracks where the paint lifts upward at the crack edges. Cracks do not necessarily require treatment unless there is associated instability.