Climate impact and innovative materials for the preservation of Built Heritage : the EC NANOMATCH project

The impact of climate change on built heritage and the development of new preventive conservation methods are nowadays topics seen as priorities by the scientifi c community involved in cultural heritage preservation. However, damage processes due to the environment-materials interaction are irreversible and often inevitable for outdoor built heritage. Research has therefore recently been focusing on the development of new materials specifi cally geared towards conservation use, such as consolidating and protective treatments, which meet the criteria of compatibility and durability. The ongoing European Project NANOMATCH has as one of the main objectives the development of an innovative nanostructured material for the consolidation of carbonate stones. An alkaline earth alkoxide as precursor of calcium carbonate has been synthesized to overcome the limits that traditional consolidating agents exhibit. As part of the research work, fi eld exposure tests are planned for the evaluation of the performance of the innovative consolidating agent in terms of effi cacy, compatibility and durability. Environmental parameters selected for their relevance to climate change are also taken into account for an exhaustive evaluation. Quarried carbonate stone samples as well as historical substrates, treated both with the innovative nanomaterial and with a commercial consolidating product, are currently being exposed outdoors to the environmental impact in four different sites: Santa Croce Basilica in Florence (Italy), Cologne Cathedral (Germany), Oviedo Cathedral (Spain) and Stavropoleos Monastery in Bucharest (Romania). In particular, Carrara marble, Savonnières limestone, Laspra dolostone and Albeşti limestone have been selected as representative lithotypes of each site. Comparisons between treatments with commercial and innovative products before/after exposure will be carried out in order to evaluate their consolidating effects on deteriorated substrates.The methodological approach and the preliminary results concerning principally the main damage processes affecting real substrates are presented and discussed.