OpenBIM Data – Starting Basics

WeZig Building IFC file visualisation during the Pre-construction Phase of the Global BIM Master from ZIGURAT

Hi Everyone, 

For a long time, we have been trying to find the time to create a series of Posts sharing best practices about exchanging data in OpenBIM format, in between ARCHICAD and other BIM tools. This is a very extensive field and many Articles are going to be necessary to cover this topic in a comprehensive way. So I would like to use this post as an introduction to an OpenBIM series of articles to start discussing this topic in smaller chunks.

Unfortunately for us, in most of the projects, we usually work on, the clients do not require BIM, which is hard to believe, but true… So quite a lot of these notions we do not practice on their daily basis. Still using ARCHICAD is a great advantage as a standard workflow to develop projects as you know, whether or not stakeholders use or require BIM.

Recently we have joined as professors the Zigurat Global BIM Manager Master. The funny thing is that due to this master we have been required to refresh all these workflows that were set aside due to the lack of use. So like re-starting practicing sports after many months without exercising, a lot of training is needed…

Courtesy from GRAPHISOFT: Approach to OpenBIM

In this Master, we are committed to teaching ARCHICAD as an Authoring tool for Design, Preconstruction and As-Built stage. All these workflows applied to the edification domain. It is important to mention this since it requires a different approach than Infrastructures and other civil works.

During different stages it is important to understand how to collaborate in an open BIM format with other stakeholders such as Engineers, Quantity Surveyors, etc… Depending on whom we are sharing the model and depending on “what purpose” the requirements will vary significantly. It is not only theory but It is exactly what happens in real-life projects.

For What, with Whom and When?

For example, Engineers might need our Architectural model as a “reference” only, in order to develop their own disciplines and BIM models. When the model is shared for conducting a “Clash Detection” the way we share the geometry, Classifications, IFC Types, Properties, etc…; must be very different.

Courtesy from GRAPHISOFT: Scopes of Different Disciplines

In the case of Consultants working on Time Planning (4D) the elements of the model should be organized in particular sets of information in order to be connected to a Time Programme. This organization will allow Planners to connect the different sets of information in the model to specific activities organized in a time Schedule.

For Cost Estimation (5D) the model must be arranged also in sets that allow Quantity Surveyors to connect those sets into Detail Cost Estimation charts. We had the chance to learn during the master how to appropriately collaborate with the Professors which are experts in the different areas such as MEP Engineering, Structure calculations and also 4D and 5D processes. 

So basically depending on what task needs to be developed, our models will need different Data and different data structures. Another thing that is important to remember is that all stakeholders perform differently their tasks depending on which stage or the project we are. The work and deliverables of an Architect or engineer, for example, are totally different if we talk about the Concept Design stage or if we refer to the Tender stage or Construction stage.

Model View Definition Explanation. Courtesy from GRAPHISOFT

Like many other ARCHICAD users we are used to extracting our quantities and prepare our cost estimations from our Model in our own particular way. But we must admit that it was great learning to have to deal with real experts in these fields that require from us IFC models that comply with their requirements. Also, it is good to remember that Architects have been doing this work since ever before BIM. Why implement these methodologies and standards then? Well, we need to improve efficiency, profitability, and sustainability in our industry. Therefore we need to implement these methods that improve collaboration between all stakeholders.

The conclusion is that depending on: Who is going to use our data, for What purpose, at What Stage (When) and other particularities of each project, the way we share our data in an OpenBIM format among stakeholders is very different. There is not such a thing as “save as IFC” in case we want to use Open Standards that are internationally accepted and practically useful. We need to work it out to understand how to prepare our data, whether it is geometric or not and then share it.

So OpenBIM standards can be very abstract and vast. I would lie if I wouldn’t admit that I struggle to understand the terminology, the processes involved, the rules, the logic and the regulations themselves. I am not a BIM manager by profession. I am an architect that uses BIM as a standard authoring tool by default in all the projects my team develops. In some circumstances, we have been managing projects using BIM and guiding other stakeholders for a better result. I have friends and peers that are absolute experts, members of Building Smart Organisation that can explain these topics much better than I do probably. 

But as important as all the aforementioned, it is to know “how” to use our tool to participate in these processes. Here is where I would like to focus my attention: on the daily practice of it. Getting back to ARCHICAD then, how does this awesome tool participate in these OpenBIM standards?


Let’s get started. In order to prepare our ARCHICAD model to be “able” to be shared in OpenBIM format, like IFC files, there are several things we need to do. But I think that it can be synthesized into 2 main tasks:

How to Model Correctly for IFC exchange? Depends on what purpose: 4D, 5D, Clash Detection, etc…
  1. Develop our Project “Correctly” for each stage and purpose.

    A model of information that is detailed enough for each stage will be able to be shared in the right way at the right stage with different stakeholders. This means that for each stage our model will be different. Please remember that when we talk about Model we are always talking about Data (Geometric and not geometric).

    We will develop our project progressively changing the level of detail (LOD) depending on the stage. It might sound too general to say “model correctly”. But a correct model will vary a lot depending on the country we are working on, the project itself, the requirements from the client, etc. But also will depend on the BEP that is prepared for the project and the EIR.

    In ARCHICAD as with any other authoring software, we can do the same thing using different tools and processes. But some of them are more correct than others when it comes to sharing our model. This is what means to choose the “right way” of developing our project. If our project is developed in a way that we can provide the Right Data for each stage of the project with different stakeholders, then our model would be successful.

  2. Use the right IFC Translator Settings.

    If our model is perfectly developed but we do not “translate” our native format to IFC or we do not “share” it properly, it might still not be useful for the other stakeholders. So after our model is developed up to the standards that we are contemplating, we need to set the correct translation Settings in ARCHICAD. The same thing applies when we want to insert IFCs from the consultants inside our model. In order to make proper use of IFCs, we need to translate them correctly into ARCHICAD.

In these series of articles, we are going to focus on point number 2: the ARCHICAD IFC Translators. Point number 1 is probably even more important. But as I mentioned before, to manage to have our model correct is something that might vary from project to project. In any case, by talking about the Translators we will also talk about the way the model is developed. So you will see that both topics are actually interlinked.

So the conclusion of this post is: 

  1. For What, with Whom and When do we share our data? 
  2. Once we know the previous, How do we do it?
  3. The 2 basics aspects of interoperability: Develop our Project Correctly and use the right IFC translators settings.

We will go more in detail in the next post where we will talk about how to use IFC translators in ARCHICAD to manage our Data and Geometry for exchange.

Thanks for reading us!