CHAPTER 10
Wall Paintings: Aspects of
Deterioration and Restoration
KARIN PETERSEN
University of Applied Science and Art, Hildesheim/Holzminden/Göttingen, Institute of
Restoration and Conservation, Bismarckplatz 10-11, D 31134 Hildesheim, Germany
1 INTRODUCTION
Wall paintings are different from “mobile” paintings executed on canvas or
panels, because they represent an integrated part of the building that cannot be
moved except by strappo or stacco in times of extreme danger. By suchinter-
ventions, however, the integral connection is irrevocably lost and cannot be
restored. In order to understand the different destructive processes occurring
in wall paintings, and any interventions of conservation and restoration required,
we have to understand the interactions between the building itself and the
wall painting concerned.
This chapter is presented from the point of view of a microbiologist but it
will not be confined to the known facts of deterioration by soluble salts and
biodeterioration. It will necessarily focus on the interactions between the dif-
ferent causes of damage and the effects of interventions, which may exacer-
bate the deterioration processes.
2 Wall Paintings as an Integral Part of Buildings
Wall paintings may be situated in completely different locations, which affect
the deterioration process to a large extent. Facade paintings are, for example,
subject to direct weathering and the extent to which they are affected by rain, hail,
snow or wind depends on the specific construction of the building. Additionally,
environmental and air pollution will endanger these paintings in a different