BIM therefore seems to offer the potential to enable those using it to better organise themselves and to anticipate problems before they occur. But what is the reality of the situation?
An innovative new method of working, BIM is shaking up the world of construction. Design offices in the electricity industry, which use BIM at the conception stage, expect this way of working to save time, and also envisage improved preparation of the project execution stage. BIM therefore seems to offer the potential to enable those using it to better organise themselves and to anticipate problems before they occur. But what is the reality of the situation? Real-world feedback and an exchange of views with experts from ENGIE Ineo, Legrand, Trace Software International and BIM&CO.
When it comes to using BIM in their projects, electricity industry professionals are faced with real and palpable problems
BIM is useful to the electricity industry because it makes it possible to anticipate and deal with problems before they occur. In practice, however, things don't always work like this. In fact, and as Trace Software's calculation and simulation manager Philippe Aupetit underlines, "BIM is still little used in the electricity industry, the reason generally being that many things are still done away from the digital model, such as load calculation, cabling, coordination with fluid systems, etc. Additionally, the detailed study work is carried out by the installers and thus not done beforehand using the BIM design model. Any clashes that occur are today still too often dealt with on the ground instead of being anticipated at the start of the project".
In order to anticipate potential problems before they occur, there needs to be better use of BIM at the preliminary design stage, using generic objects, followed by the use of manufacturer objects at the detailed design phase. Additionally, and on the topic of generic objects, Patrick Valton, Corporate BIM Manager at Legrand, observes that "generic objects currently only come in the form of entire equipment units, and it is important to be able to move to a system that allows you to include the interactions between each individual element".
Another problem associated with the use of BIM design software is that the currently available solutions cannot handle the concept of the cable, the most important element in an electrical installation. This makes the use of industry specific specialised software necessary. In fact, for cable routing purposes in Revit, for example, you have to use the piping feature.
Design offices are also faced with the lack of harmonisation that exists across BIM object properties: each different trade and each manufacturer has its own specific conventions. Wattage and number of phases are, for example, two pieces of data that electrical industry design offices need and require but for which the BIM object terminology varies from one manufacturer to the next. This lack of standardisation makes using BIM objects a tricky process, yet they are a necessary requirement at the design stage. Though the PTNB ("Plan Transition Numérique dans le Bâtiment" – the French building industry digital transition plan) and trade federations are working hard to achieve BIM object standardisation, the process remains long and painstaking; it represents a hindering factor for projects.
And finally, Damien Sellet, BIM Manager at ENGIE Ineo, reminds us that "in France, digital models are not yet contractually binding. The "paper" contract takes precedence over the digital model, especially where there are differences, such as with the power requirement, for example". For reasons of practicality and convenience, therefore, it is predominantly generic objects that are used at the moment. In some countries, such as the United Kingdom and Singapore, digital models are contractually binding and the objects used are the manufacturer ones. There is still a need to prepare ourselves for the future.
Despite its relative newness, BIM is gaining popularity with teams due to the fact that it is already proving useful. "You get better organisation in the design of the control/plant rooms, and you save significant time when modelling complex installations, thanks, for example, to the modelling of the staircases," underlines Sellet. BIM is also of valuable help when the building is in actual use, making it easier to replace a product installed in the building, consult its maintenance guide or carry out a compliance upgrade.
We have seen that the issue of data harmonisation is a hindering factor for companies, due to the present lack of consistency and conformity displayed by the information provided by manufacturers. This stems from the various different and constantly evolving norms and standards that exist. Fortunately, innovative solutions such as Onfly, which is used by ENGIE, provide a way of brilliantly addressing these issues, making it possible to obtain a referencing system for all BIM objects that is specifically adapted to the company's requirements. BIM&CO has actually compiled a special dictionary of linked properties that can be used to transcribe the data associated with a BIM object to a company's own referencing system, or to that of a specific software package or standard.
To address the problem of file size, BIM&CO has developed Smart Download, a technology that enables the user to select only the data they specifically require when downloading. Once the model has been sent to another participant in the BIM process, that third party can then in turn update the object with the data they are interested in, which thus keeps file sizes to an optimal minimum. These features are very useful in the context of electricity and fluid coordination, providing a library of common objects for use in these two specialist areas, complete with the data required by both disciplines.
When modelling their products, manufacturers have to take formats and standards into consideration in order to be able to assure their users that their objects are both suitable and of a high quality. As the first stage of work it is currently doing on security lighting, leading electrical solution provider Legrand has chosen to seek the involvement of its users in France, Belgium, the Netherlands and Spain in order to obtain real, tangible feedback. It is in this same context that BIM&CO has put together a select group of experts from amongst the company's users. The idea behind the group is to provide the manufacturer with advanced access to real-world feedback and specific usage cases that can be used to develop genuinely useful and relevant BIM objects.
This same methodological approach is also being applied within the research group set up by the Gemelec and Ignes trade federations for the purpose of providing high quality generic objects for use in the electrical sector.
Things are also moving forward with respect to the carrying out of calculations using digital models. Software publishers are keeping a close eye on the way the use of BIM is developing and evolving in practice. The elec calc™ BIM solution actually makes it possible to import digital models from Revit, ArchiCAD, etc.. using IFC4. The user can thus view the model and retrieve all the electrical terminals in elec calc™ BIM in order to use them for their calculations. In fact the user connects to BIM&CO anyway to access supplementary manufacturer data.
Electricity is thus another sector that is also facing numerous challenges linked to the digitalisation of the world of construction. However, manufacturers and industry professionals are already working hand-in-hand to try to respond to these challenges via various different solutions, thus laying the foundation for a promising future for BIM in this field…
Comments gathered during the BIM&Electricité – BIMWorld Paris 2018 workshop.