Electrical tomography for the monitoring of water moisture in painted walls and ceilings

Painted walls represent a great heritage of cultural and artistic value. Unfortunately, these works of art, especially the frescos, are constantly attacked by moisture and salt content in the wall plaster, thus, particular attention has to be paid on their conservation state. Nevertheless, there are no many instruments that permit to detect the wall state without causing damages to the paintings. For these reasons, a non-invasive measuring system, which is based on resistivity measurements, is proposed to investigate the moisture content in painted walls and ceilings. The method is able to provide information not only at the wall surface but also at few centimeters beneath the painting, thus allowing one to detect dangerous situations before the deteriorating effects take place. Despite the attention has been focused on the conservation of work of arts, the proposed system can be employed in many other fields including the building sector in general.