In the proposed Open BIM workflow, the models and design hypothesis each designer has developed remain in their private domain and are not shared in the cloud.
This way, the responsibility limits are guaranteed, as is their supervision on behalf of the specialised agent (in the updating process, for example).
The data introduced and intermediate results, such as the forces or moment resistance of a beam, the design intensity and resistance of a conductor or the assigned weather conditions to calculate thermal loads, are the exclusive responsibility of the person who carried out the corresponding calculations using specific files of the application used for each case, which are not uploaded to the BIM project and have nothing to do with the IFC files that are shared.
For the aforementioned examples, users should upload to the BIM project, in IFC format, the assigned steel section or reinforcement of the beam, the section and type of conductor used or thermal loads that are finally calculated.
Contents of the IFC files
In the proposed Open BIM workflow, the generated IFC files, initially, do not include technical information on the elements included in the BIM project.
Data such as the required electric power, the heating power that is generated, the emitted sound level or performance curve, for HVAC equipment, are not included in the BIM project; only the corresponding brand and model.
It is in specialised applications, which are sensitive to this designation (brand and model), where the specific technical information of the corresponding analysis model is generated and maintained.
This way, the size of the interchange files is drastically reduced, and allows for an implementation that is progressive, specialised, coherent, one hundred percent adapted to the applicable standards, and also, sensitive to the specific design criteria of each manufacturer, for the different element types included in the BIM project.
Contents of the BIM project
The information of the BIM project is, initially, made up of the entities contained in the IFC format files, which are generated by the different applications used in the Open BIM workflow.
However, during the development of the project, and as an additional result of the specialised applications, it may be convenient to include and share complementary information using files annexed to the project, which can be in different formats, not necessarily standard formats.
Some examples of these types of files are: drawings (DXF, DWG, etc.), bills of quantities (BC3, etc.), documents and reports (PDF, RTF, TXT, etc.), photographs and renders, forces obtained from structural analyses, point clouds generated by laser scanners, etc.
This requirement, inherent to the development of projects, is considered in the Open BIM workflow using the standard capacity of files in IFC format to include links to other files. In other words, for these additional files to be able to form part of the BIM project, they must be included in the IFC files that are generated by including the corresponding links. This way, the role of the IFC files as a guide or container of all the information of the project is maintained, without losing the possibility of attaching any type of information or complementary result, and always knowing the origin of the information, and therefore, who is responsible for it.