Micro Climates and Moisture Induced Damage to Paintings

Marion F. Mecklenburg

Because of cold climates and minimal insulation in the walls of many buildings, the inside surfaces of exterior walls reach the dew point. Very high humidity levels and even condensation can occur on these surfaces. On hot summer days these same walls can reach elevated temperatures where the relative humidity near the interior surface can drop to as low as 30%. The zone close to such walls represents micro-climates that can vary widely from the intended “controlled” climates of museums and galleries. As a consequence considerable damage to works of art can occur. This paper discusses some of the mechanisms that cause the damage to canvas paintings.