The Monument Diagnosis and Conservation System (MDCS) damage atlas ontology (MDCS-O) is derived from the original MDCS damage atlas web application (https://mdcs.monumentenkennis.nl/damageatlas) hosted by TNO, TU Delft and the Dutch Rijksdienst voor het Cultureel Erfgoed. While the web application is designed as an interactive support tool, this web ontology makes it possible to use the uniform MDCS damage atlas terminology to classify construction damage cases defined in an RDF dataset. It is defined as an extension of the generic Damage Topology Ontology (DOT, available at https://w3id.org/dot#). The web ontology version of the MDCS damage atlas was created by Mathias Bonduel (KU Leuven) during his PhD research (2017-2020) funded by the Research Foundation Flanders in the form of a Strategic Basic Research grant (grant agreement 1S65917N).- Version 1.0.0: initial public version