## 4 Discussion
### In Reference to the Structure of the HBIM Model  
As stated in the corresponding section, the structure of the model is subject to decisions on the nature of the entities that comprise it and on the definition of their relationships. These decisions would be endowed with great freedom if the process were to be carried out with a set of open source software applications (a perfectly valid option, and very interesting for future lines of progress). However, if commercial applications are chosen, it is necessary to carry out a prior adaptation process: The conceptual model initially proposed at the theoretical level must be translated into the systematization and hierarchy of entities and relationships established in the internal software code. This adaptation process will be different depending on the BIM platform chosen, but it is considered that it is achievable in any of the currently available platforms, regardless of the initial theoretical model. Thus, the effort to be used in adaptation will become one of the main variables that would be combined to make a suitable choice of software.  
For the generation of the HBIM model described in this research, a specific commercial BIM software was used. It was not been possible to reproduce the methodology proposed in other commercial software due to time issues. That work is pending for future projects. The successful translation of the initial theoretical model into the object structure of BIM application is based on aspects related to categorization of objects and their visualization based on information filtering. These aspects are developed in all BIM software due to the very nature of this technology. Therefore, although there are variations in the implementation of such aspects in different software, it can be said that the proposed methodology is transferable to any commercial BIM application.  
In another order of things, the authors of this work defend the statement that preventive conservation should include complete buildings and not just a part. The general methodological proposal of the authors on the application of BIM in heritage architecture includes not only preventive conservation but also the set of actions that encompasses the concept of guardianship. This refers, in general, to knowledge, management and conservation/intervention in these buildings, including scopes like structural analysis (in the line of works such as those published in [60,61]).  
This work refers to a concrete experience of applying new methodological aspects in the modeling process and information management in an HBIM model, focused on the action of preventive conservation. This experience arises from a collaboration commitment between the research group of which the authors are part and the company dedicated to the preventive conservation of the facades of the Cathedral of Seville. The company provided information on the current state of the building and on the treatments applied, and the authors provided a method for the documentation and management of that information. Additionally, a simplified modeling of the interior spaces and the material elements that surround them was introduced with the objective of establishing metric and trace relations with the facade elements, thus supporting new analyses on the historical evolution of this part of the temple.