In the field of built heritage, a huge amount of data describes the state of monuments: documentary data (texts, sounds, images) as well as analytic data from sensors, provides historical, archeological and constructive information. These data, produced by experts coming from several fields, are the foundation for the creation of new information through scientific observations. The problem is that these data are not related nor spatialized. Nowadays we are able to generate extreme accurate 3D model with throughout images-based or laser scanner acquisition. However these 3D models do not carry information regarding their morphological complexities. The design of an ontology for the conservation domain seems to be the best solution in order to obtain understandable entities thanks to their own data related between them. This article present the first attempt of a development of a web information system based on spatialized images semantic annotations tool, related to a domain ontology describing knowledge regarding stone degradation phenomena. Our approach is to produce a domain ontology able to document and therefore provide a framework able to help the decision-making process of experts in the cultural heritage conservation domain. The information annotated with the use of this ontology can enrich not only the scientific observations, but also to help to create new knowledge. In this way, it is possible to link and gather quantitative and qualitative aspect into only one information system. We will propose several example and queries able to exploit the reasoning power of the above information system.