Ifc export in 2027 - mapping parameters severely lacking

TSwayze · ‎08-11-2026

One of the best things about Revit has been how easy it is to add or modify custom psets and parameters in IFC exports. (Especially compared to other BIM software I use which shall not be named) I can modify or add a parameter in a few seconds by changing a line in a text file without even having to open Revit, and everyone at my company refers to this text file so deployment is instant.

However this has changed in Revit 2027, replaced by a cumbersome menu with many sub menus, requiring 20 clicks to do what could previously be done in 2. Now wasting my time is one thing, but this menu is also severely lacking as far as I can tell.

Many parameters are missing from the export menu.
You can't export two different parameters, from two different element types, to the same ifc parameter

See my screenshots. You can't type in the "Revit Property" box, you must select from a list. If I select IfcPile I can see parameters from "Generic Model" only. If I select IfcBeam I don't get any parameters at all. If I select a category like "Structural Framing" I get very few parameters, where is Length and Cut Length??

If I attempt to export two parameters to the same one, like "Comments" to "Commentz" for Walls, and "Comments 2" to "Commentz" for Floors, it won't work. Only the first line is included and they both export "Comments".

It's not possible to have two property sets with the same name. I always had this in the past. Like I mentioned not all parameters are the same across different categories, I also don't want to export all parameters for all model elements.

Why is it so lacking and cumbersome am I missing something? Is there any way to export using the pset.txt files instead?

Pavankumar_H · ‎08-14-2026

Hello @TSwayze,

Thanks for reaching out to us on Forums.

I understand that you are looking for a way to export custom parameters to IFC in Revit 2027 without relying entirely on the updated, more menu-driven IFC export interface.

It is still possible to export user-defined/custom properties using the traditional PSet.txt file approach. This can be useful when you need the flexibility to define or modify custom IFC property sets through a text-based configuration.

Please refer to the Revit 2027 Help documentation for “Export User Defined Properties to IFC.” Click on the link to know more. The workflow describes how to define user-defined property sets and map the required Revit parameters for IFC export.

You can generally proceed by:

Configure the required custom/user-defined property sets using the PSet.txt file.
Ensure the Revit parameter names and applicable IFC entities are mapped correctly.
Enable the appropriate user-defined property set option in the IFC export configuration.
Export a test IFC file and verify the resulting properties in an IFC viewer.
If a parameter is missing, confirm that the parameter contains a value and that the PSet definition and IFC entity mapping are correct.

If you are seeing different behavior compared with an earlier Revit version, please share the specific Revit 2027 build, a sample of the PSet.txt definition, and the expected versus actual IFC output. Please avoid posting any project or account information that may be confidential.

For further investigation, you may also create a support case with Autodesk Support and attach the relevant files, logs, and screenshots for deeper analysis.

Kindly, click on 'Like' or 'Accept Solution' if this has led you to direction in order to resolve the raised issue.

Thank you!

TSwayze · ‎08-17-2026

I know how to make pset.txt files, that's all the solution tells me how to do.

3. Enable the appropriate user-defined property set option in the IFC export configuration.

How do you do this in Revit 2027? This option has been removed and replaced with the menu based export. I am on Revit 2027.2.

navya_gelli · ‎08-23-2026

Tagging in @Pavankumar_H to see if some additional help can be provided.

Navya | Community Manager

Pavankumar_H · ‎08-24-2026

Hello @TSwayze ,
Thanks for the response.
I sincerely apologize for the length of time it took for us to respond.
Can you please try enabling the option from here? PFA image FYR.

Please let me know if this is helpful.

I look forward to hearing from you soon!

Kindly, click on 'Like' or 'Accept Solution' if this has led you to direction in order to resolve the raised issue.

Thank you!

TSwayze · ‎08-25-2026

Pressing that button brings up the menu I screenshotted in my first post. It is not possible to define a custom pset.txt-file in that menu and the the options in the menu are very limited compared to using a custom pset.txt in the past.

Can also mention that I usually use a dynamo graph to export IFC files. It is possible to override the psets here in previous Revit versions using the following code, but this section is ignored for Revit 2027. (It is in PythonNet3 and everything else about the script works in 2027)

    if file_exists(custom_pset_path):
        set_prop(ifc_config, "ExportUserDefinedPsets", True)
        set_prop(
            ifc_config,
            "ExportUserDefinedPsetsFileName",
            safe_str(custom_pset_path)
        )

        messages.append(
            "Custom pset file set: {}".format(
                safe_str(custom_pset_path)
            )
        )
    elif safe_str(custom_pset_path).strip() != "":
        messages.append(
            "Custom pset file not found: {}".format(
                safe_str(custom_pset_path)
            )
        )

Using Revit 2027 is not an option at my company until this has been fixed.

Pavankumar_H · ‎08-25-2026

Hello @TSwayze ,

Thanks for reaching out to us on Forums.

Thank you for the additional details and for sharing the Dynamo/Python workflow. I understand that the custom PSet.txt configuration that worked in previous Revit versions is no longer being honored in Revit 2027.

Since this requires a closer investigation of the Revit 2027 IFC export behavior and your specific workflow, I recommend creating a support case with Autodesk Support. Please include the Dynamo script, sample PSet.txt file, a sample Revit model if possible, and the expected versus actual IFC output. This will allow the support team to reproduce and investigate the behavior further.

Kindly, click on 'Like' or 'Accept Solution' if this has led you to direction for the raised issue.

Thank you!

Pavankumar_H · ‎08-26-2026

Hello @TSwayze ,
I would like to inform you that, I did some research with our internal engineering team on the issue you have raised with us here.

Here is the detailed explanation what I got for you on the issue raised.

"The new IFC Parameter Mapping UI in Revit 2027 is an intentional change. It replaces the previous text-file-based workflow (pset.txt) with a graphical interface accessible via Export IFC > Modify Setup > Parameter Mapping. The goal is to give users a more integrated way to map Revit parameters to IFC property sets and create user-defined property sets — without needing to maintain external text files.

You can find more details in the official documentation here:

Regarding the specific issues you raised:

Empty property lists (e.g., IfcBeam showing no parameters, IfcPile showing only Generic Model): This is a known issue that the development team is aware of and has been addressed in an upcoming update. We do not and ETA for the release as of now.

Mapping two different Revit parameters to the same IFC property name across different categories / Duplicate property set names: We appreciate you flagging these limitations. Your feedback has been noted and passed along to the development team for consideration in future improvements.

We understand this is a significant workflow change, especially for users who were efficient with the text-file approach. Your input helps us prioritize improvements to make this new interface as flexible and powerful as the previous method."

I hope this helps you.

Thank you for taking the time to share this with Autodesk.

navya_gelli · ‎08-31-2026

Hello @TSwayze,

Have you had a chance to review Pavankumar_H reply? Did it help resolve your question?
If it did, please consider marking it as the accepted solution so others can easily find it. If not, feel free to share an update and the community will be happy to assist further.

Navya | Community Manager

filip.kabelis · ‎09-09-2026

I see this is quite fresh, still, when are you planning on fixing the possibility to map multiple Revit parameters to one IFC parameter?

It's quite infuriating since it worked for many past years.