## 2 Methodology
The procedure to integrate GIS and BIM model files into the same platform (PHASE 2) involves a simple file import through the GIS software's import menus, requiring five key steps (Figure 3). The speed and effectiveness of this integration depend on the GIS software used, which may require specific plugins or programming to handle the BIM files and their attributes. Folders are created on the server to store model-related files (documentary source of the virtual library), and links to access documentation are extracted for inclusion in the GIS browser. Additionally, databases such as BIM attribute tables and Excel sheets must be created, linked to BIM elements, and populated with the collected information that has not been previously integrated in the BIM model. Pop-up windows should be configured within the GIS platform to display model element information. Finally, once the models are integrated into the GIS and BIM platform, they can be applied to multiple applications. This article focuses on their application for building facilities maintenance management (PHASE 3), through a procedure structured in four steps (Figure 4). For step 1, _Define spaces, assets and systems/subsystems_, Figure 5 shows the hierarchical structure of digital elements in a BIM model. These elements are called \"types\", which are different components belonging to a digital family. Variations in parameters within the same type are referred to as \"exemplars\". Systems are collections of types working together to provide a service (e.g., an electrical system or a facade wall system). Some systems consist of subsystems that interact to provide a service (e.g., the pumping subsystem in a boiler system). Model spaces are areas where interrelated types and/or systems are organized (e.g., classrooms or boiler rooms). In step 2, _Link and Configure a Computerized Maintenance Management System (CMMS-3D) and list the stakeholders_, the GIS-3D platform containing the BIM model must be configured to manage its attributes, enabling direct access to the CMMS through GIS pop-ups. This involves adding links to the BIM model's parameters for easy access. To manage building maintenance in 3D, software that allows the BIM model to be integrated into it is necessary, allowing the configuration of maintenance activities without modifying the model's initial geometric parameters. Stakeholders will be listed and registered in the CMMS-3D for efficient task assignment. In step 3, _Develop pre-maintenance activities_, incidents that disrupt or reduce building service quality are detected and recorded in the CMMS-3D model. In addition, prior to executing maintenance, a comprehensive maintenance plan is developed by reviewing all available asset information, including equipment, history, plans, measurements, materials, tests, location, physical barriers, and permits. Relevant stakeholders and resources are identified, and for external maintenance, estimates are obtained and contracts signed. Once the incident is administratively processed, it is configured in the CMMS control panel, allowing personnel assignment and work order setup to begin maintenance and supervision. Finally, in step 4, _Execute and digitally superuse maintenance tasks_, the 3D digital supervision of maintenance can be developed through a CMMS. The selected CMMS should facilitate linking the assets, spaces, and systems/subsystems of the buildings with all existing documentation, to ensure its accessibility by the stakeholders, at any time during the life cycle of the building, allowing the exchange of information, in real time, of the entire maintenance process to be documented during its supervision. Figure 5: Hierarchical structure of the digital elements of the model.