The paper deals with a rehabilitation of the historic building of Carmel Monastery next to the Prague Castle. A structural survey of building was carried out and the historical drainage and ventilation system was identified. Based on structural survey in-situ the reasons of failures were analyzed and remedial works of historic monastery were proposed.

During the detailed moisture survey of the former convent the historical drainage and ventilation systems were found and documented. This paper describes an interesting discovery in the basement of the monastery and presents conceptual design of remediation pointing out, at the same time, the risk factors. Methods using new materials including nanostructures are also mentioned.

The paper deals with the analysis of performed repairs and the current state of drainage and ventilation system of the Plasy convent and their evaluation. The Plasy historic water system is described in detail based on the results of a long-term field and structural survey. At the same time, unsuitable interventions, particular the application of chemical barrier, were analysed. Recommendations for further measures in the framework of the rehabilitation of the whole convent are made.