IFC for the Win?
In short, no, not for what we need. Before you start cursing me up and down, I will explain below. Now I want to welcome you to 2025, the Year of the Snake according to the Chinese calendar. I hope you had a wonderful holiday with your family and friends and were able to take that much-needed vacation from work to unwind, I know I did (two weeks’ worth). As I inch one year closer to that 50-year mark (this time next year), I am definitely feeling it in my bones.
What is IFC
I am going to explain why IFC doesn't work for our purposes, let me define what IFC is.
The “textbook” definition of IFC is as follows. In the AEC (Architecture, Engineering, and Construction) industry, IFC, or Industry Foundation Classes, is an open, neutral file format that plays a crucial role in facilitating interoperability and collaboration among different software applications within Building Information Modeling (BIM). Developed by buildingSMART International, IFC ensures seamless communication between project stakeholders and reduces the risk of data loss during software exchanges.
As an open standard, IFC is not tied to any proprietary software, allowing it to be implemented freely across platforms. This openness makes it a cornerstone for fostering collaboration in BIM workflows, as it provides a common language for representing building elements, spatial relationships, materials, and their associated properties. By standardizing these aspects, IFC ensures that detailed project information can be exchanged consistently and comprehensively.
IFC files come in various formats, such as .ifc,. ifcXML, and .ifcZIP, and are used for a wide range of applications in the AEC industry. For example, they enable architects, engineers, and contractors to coordinate more effectively, support clash detection, and perform quantity takeoffs and project analyses. Furthermore, IFC is critical for adhering to BIM Level 2 and ISO 19650 standards, ensuring compliance with industry’s best practices.
The format has evolved over time, with widely adopted versions including IFC2x3 and IFC4. The latter offers improved capabilities for geometry representation, performance optimization, and metadata integration, making it a preferred choice for advanced BIM workflows. In April 2024, IFC 4.3 was released and is supported by Revit 2025.
By serving as a universal bridge for information exchange, IFC has become indispensable in creating collaborative, efficient, and standardized processes within the AEC industry.
Now on “paper” that sounds like an amazing thing but here is where things take a turn.
IFC and Revit
Revit 2013 was the first version to support the import/export of IFC files natively. This version included built-in IFC import/export functionality, enabling users to integrate IFC workflows more effectively into their Revit projects. Before this release, IFC compatibility in Revit was managed through external plugins or extensions. With the introduction of Revit 2013, IFC functionality became integrated directly into the software, enhancing interoperability for BIM workflows.
Revit's IFC capabilities now include support for newer IFC schema versions, advanced mapping tools, and enhanced performance for handling large models. This ongoing development ensures that Revit remains a key tool for collaborative BIM processes.
Fast forward 10 years to Revit 2023 and this is where IFC starts breaking down and not working for our needs. Revit, as of version 2018, lets you link an IFC file into your Revit model. This method is most effective with IFC4; however, Revit 2023 does not fully support IFC4.
You see, we have a client who only uses ArchiCAD and prior to ArchiCAD v27, they would send us IFC files. When I first started at Garver, the projects with this client had a lot of complications and I was asked to work out a better way. In my extensive testing I tried several different options with varying results. Let’s look at those outcomes.
Link IFC
When linking the IFC file to Revit, the translation to Revit was less than stellar. Everything in the linked model was categorized as Generic Models but they were also Model in Place Components. The only control you have of the IFC models’ phase is by using the Phase Mapping on the link. This does not always put things in the correct phase. All of this completely negated any view templates that were being used. If a user did not want to see something in the model, they had to right-click, hide in view separately for each element and in every one of our views. If the project scope was full MEPF, we had dozens of views, and I am sure you can imagine how time-consuming and frustrating that was. When linking an IFC, Revit also created a couple of extra files, a . ifc.rvt and .ifc.sharedparameters.txt.
Open IFC
Using Revit’s open IFC converts the IFC file into a Revit file. This method also proved to be painful with all elements still being Model in Place Generic Models. Other random things would occur like all the walls being individual sections, walls completely missing or random boxes everywhere for openings. With each file we received, I never knew what I would get. We at least had more control of the file, could make it work shared and edit an element to change its category if we had the time.
What I did not know when I first started looking into a better workflow for working with IFC was that importing and opening of an IFC file looked at the Import IFC options dialogue found under File à Open à IFC Options. I guess Autodesk is saying “Open” and “Import” are the same thing. This dialogue allows the user to specify which IFC Class Names and their IFC Type are mapped to which Revit Category and Sub-Category. As you can see from the screenshot, some of these IFC Class Names are already mapped. I did go through the entire list and added some additional IFC Class Names and Types. Then I mapped those IFC Class Names to the appropriate Revit Categories for the categories that matter for MEP. You also need to specify a template. This can be a custom template or one of the Autodesk provided templates, which is what I am doing.
Figure 1 - Import IFC Options
What is not clearly identified is the exporting of the IFC file. When exporting to IFC from ArchiCAD, those using ArchiCAD need to properly map the ArchiCAD elements to the correct IFC Class Name. I don’t know what that looks like since I do not have ArchiCAD but from what I can tell it should be one of those who set it and forget it things. This step is crucial in the process. At first almost every element exported from ArchiCAD was exported as IfcBuildingElementProxy, which is the IFC equivalent to generic elements. Per the Import IFC Options settings, this was set to Generic Models by default. This explains why everything was categorized as generic models. Some of things we were dealing with for quite a while were Plumbing Fixtures were categorized as Air Terminals or Generic Models or Ceilings were categorized as Floors. Once we identified the issues, it required several iterations and discussions with the client to achieve a satisfactory export format.
Now, while we worked out most of the kinks when importing the IFC into Revit, there are still a few things that are a pain point. The elements are mostly categorized correctly but everything is still a Model in Place component. When importing the next updated IFC model, Revit gives everything a new GUID, so if any of our Revit families are hosted to the walls or ceilings (which most of our Electrical content is), they now become orphaned or shoot off into space. If our Electrical team does not want to deal with that, they will draw reference planes everywhere and host our Electrical content to them, but they do not move if a wall or ceiling moves.
Earlier I mentioned that prior to ArchiCAD v27, they would send us IFC files. In ArchiCAD v27, the ability to export directly to a .rvt file was added. While this may be viable for some, I have found that despite that ability, the importation of the IFC file (IFC2x3) works best in Revit 2023, which is our current standard version. I know in Revit 2024 and 2025 IFC interoperability has been improved and IFC4.3 is supported, but we are not using either of those versions for these projects. Hopefully in the next few months we will make the switch to Revit 2025.
Lastly, I am not using the standard Open IFC within Revit anymore but rather the IFC Exchange with ArchiCAD Revit add-in. This add-in still utilizes the Revit Import IFC Options but does something different on the back end and I have found that this is the best method for our needs in lieu of the Link IFC not working that well in Revit 2023. I will say that even though the initial process was rather painful, the client and I have since worked out a process that works for us on the many projects we have together. We anticipate transitioning to Revit 2024 or 2025 as our standard version, which will enable me to explore additional options such as utilizing IFC4 or IFC4.3 for integrating into our model and streamlining our project coordination.
Figure 2 - ArchiCAD Revit Add-In
IFC and Newforma Konekt
What is Newforma Konekt you ask? Well, Newforma Konekt is a cloud-based project information management (PIM) platform designed for the AEC industry, facilitating seamless collaboration, document management, and communication across project teams. It streamlines workflows by integrating with popular design tools, like Revit or Navisworks and offers real-time access to critical project data, ensuring teams stay connected, organized, and efficient throughout the project lifecycle.
Figure 3 - Newforma Konekt Logo
We recently rolled out Newforma Konekt on a couple of pilot projects as well as provided those project teams with training on how to use Newforma Konekt. For these projects we are primarily using it for Issue Management during our design and development for Revit and Non-Revit project team members.
Currently, Newforma Konekt does not access Revit models through the Autodesk Construction Cloud unlike similar tools. This has been part of the frustration I have been experiencing because we need to export IFC files from the Newforma Konekt Revit add-in. manually doing this for each model can take 30-60 minutes or more depending on how many elements are being exported.
Newforma Konekt Add-in
There are basically two main components of the Newforma Konekt add-in, the issues dialogue and publish (export). The add-in does not automatically detect which project you are working on, so you must manually select your project hub as well as the Newforma Konekt project from the drop-down list. This project you create in the Newforma Konekt project hub is also independent from the ACC project you have. You must select the hub and project before you can access the Publish portion of the add-in.
Figure 4 - Newforma Konekt Add-in for Revit
Figure 5 - Newforma Konekt Add-In tab in Revit
Publishing
When publishing from the add-in, you need to select the 3D view you want to export. You will need to make sure that the view has everything visible you want to see. You will also need to give the file a name. We are just using the discipline as the name, e.g. Architectural, Structural or MEPF. Under Discipline, you can select the discipline(s) that apply to the model being exported. This is pulled in from the Project Settings of the Newforma Konekt project you created and can be established in a template. If a model with the same name already exists in the project, you can specify that in the “append a new version” tab. Once the model is published and processed in the project, the file will now show a new version. Next you will want to select all of your sheets to also get published with the 3D model. Not to get off track, but you can turn those sheets on and have them overlayed on the 3D view in the Newforma Konekt Viewer. This is similar to how Model Coordination does it BTW.
Figure 6 - Publish Dialogue
Before you hit the Publish All button, you are going to want to modify your setup. Another annoying thing about the process is that you must modify your setup each and every time you manually publish. There are a couple of things I always change though. First, I change the IFC version to IFC4 Reference View. This has given me the best results when viewing the model. Secondly, under the Level of Detail tab, I change it from Low to High. For the rest of the settings found therein, I left them as their default.
Once that is done, just hit Publish All and sit back and wait. Be warned though, you cannot use that instance of Revit while the export is happening either so you will have to find something else to do while it goes through the 1000s of elements in your model.
There is an option to Schedule a publish as well. I highly recommend that you do this from a remote workstation and not your daily driver of a computer. The computer where the scheduled publish was created needs to be powered on. I found out the hard way several weeks after I scheduled a publish as to why the file had never updated from the initial publish. I did it from my work computer and I always shutdown when I am done for the day and the scheduled time was for a Friday afternoon. This process also utilizes the computer's Task Scheduler. When the scheduled publish begins, it initiates an instance of Revit. However, even if Revit is already running, you will not be able to interact with the newly opened instance.
Figure 7 - Schedule a Publish
Once I figured out that the scheduled publishes were not happening, I created the publishes from a remote workstation I was given access to. I quickly ran into other issues though. Over the course of a few weeks, some of the weekly publishes did not happen and some of them happened but failed to process. Our Design Software Manager and I had numerous conversations via email and a couple of conference calls with Newforma Support to figure out what was going on. We eventually did figure it out.
In the instances where the models failed to publish, somehow the Shared Coordinates of the models were different. I am not sure how that happened, the projects were set up using Shared Coordinate. Once that was corrected, those models began to work as scheduled. The instances where the publishes happened but failed to process was an issue on the Newforma Konekt side of things that is. They are not sure what caused them to fail, but as of the time of this writing, this issue persists. If we are going to have to manually publish our models to Newforma Konekt, that workflow will consume us, and we will quickly abandon its use and not move forward. Now if Newforma Konekt can connect directly to the Autodeck Construction Cloud and pull the Revit models directly into their system, that would be the best option moving forward and exporting would not need to happen. I think they could just grab a copy of the latest model published from Autodesk Docs.
Conclusion
In conclusion, while the concept of Industry Foundation Classes (IFC) holds great promises for enhancing interoperability and collaboration within the Architecture, Engineering, and Construction (AEC) industry, it falls short of meeting our specific needs currently. Despite the advancements in IFC standards and the integration of IFC capabilities in software like Revit, the practical challenges we face—such as inconsistent categorization, cumbersome workflows, and the limitations of current software versions—hinder its effectiveness for our projects.
Our experiences with linking and importing IFC files into Revit have revealed significant inefficiencies and frustrations, particularly when dealing with complex models and maintaining accurate data throughout the project lifecycle. The introduction of tools like the ArchiCAD Revit add-in and Newforma Konekt offers some relief, but they also come with their own set of challenges and limitations.
As we look towards the future, the potential for improved IFC interoperability and more seamless integration with tools like Autodesk Construction Cloud remains promising. However, until these solutions can fully address the pain points, we've encountered, IFC will not be the win we hoped for. We remain committed to exploring and adopting the best practices and technologies that will enable us to deliver high-quality, efficient, and collaborative project outcomes.
