15 th Quantitative InfraRed Thermography Conference 1 License: https://creativecommons.org/licenses/by/4.0/deed.en Monitoring the Scrovegni Chapel crypt by IR thermography by Paolo Bison§, Alessandro Bortolin¨, Gianluca Cadelano¨, Giovanni Ferrarini§, Fabio Peron©, Piercarlo Romagnoni© and Antonio Stevanª § CNR-ITC, C.so Stati Uniti 4, 35127 Padova, Italy, paolo.bison@itc.cnr.it ¨CNR-ISAC, C.so Stati Uniti 4, 35127 Padova, Italy ©University IUAV of Venezia, S. Croce 191 – 30100 Venezia, Italy ªSYNCRO srl, via Portello, 91 - 35129 Padova, Italy Abstract The Scrovegni Chapel in Padova (Italy) is worldwide renowned for the fresco cycle due to Giotto. The outstanding value of this work of art requires a continuous monitoring of its state of conservation. Starting from 1995 a Scientific- technical Board coordinates the many initiatives and, among them, several measurement campaigns by IR thermography had been carried out. More recently, the hypogeal environments under the Chapel has been considered due to the presence of water which frequently submerges the floor and part of the vertical structures of the crypt. The present work reports on the activities and the results of those surveys. 1. Introduction On 1300 AD, Enrico Scrovegni, who became rich by lending money, commissioned the building of a new chapel, presumably to atone for the sin of usury. He hired Giotto, the most recognized painter of the time, to decorate the inner walls of the chapel. Very little is known of the Chapel from the time when it was built and decorated, until 1881 when the municipality of Padova bought it in a state of decaying. Large restoration was done at the end of the XIX century and in the sixties of the last century. In 1995 a Scientific-technical Board settled down to coordinate the surveys of the conservation of the building structure and the preservation of frescos [1,2,3]. In the same year a systematic monitoring of the microclimatic variables began, together with the installation of a HVAC system to maintain temperature and humidity within acceptable ranges [4]. That was necessary to minimize the effects of the new dangerous appearance of the air pollution that appeared to be so harmful for the colours of the frescos. In 2002 the Chapel was reopened after being submitted to a new round of restoration and cleaning of the Giotto cycle by Istituto Centrale del Restauro. In 2016 a new plan was presented, focused on the Chapel Crypt (see Figure 1), whose floor is often affected by water sourcing from the ground. The new measurements campaign started in November 2017 and is still ongoing. In and around the time of the last restoration, IR thermography was utilized successfully in the Chapel as a Non- Destructive-Testing – Non-Contact technique, capable of revealing hidden structures, fresco detachment, cracks and humidity [5]. The results gave useful information to the restoration activities. It has been considered again in the frame of the new monitoring campaign of the Chapel Crypt, to identify the humidity rising on the walls and to evaluate if such humidity can reach the upper floor and affect the Giotto painting [6]. Fig. 1. The Scrovegni Chapel with the Crypt underneath. 10.21611/qirt.2020.072