BIM Model Import Troubleshooting Guide

This troubleshooting guide helps you resolve issues that may occur when importing BIM or scan models. It outlines the most common causes and provides steps to help you successfully import your model.

This guide includes the following sections:

• File format not supported
• Imported model is empty
• The file in an invalid format
• Trouble converting your file

File Format not Supported

This message may appear when you try to import a file format that is not supported. Please check that the file you are importing is one of the supported formats:

BIM and Scan Models

Most programs allow you to export your model using the IFC open BIM format (.ifc), which helps ensure compatibility when working with BIM models. 

Below are common unsupported file types and recommended next steps:

SKP (SketchUp)

SKP files are native to SketchUp and are not directly supported. 
To use a SketchUp model in cmBuilder, export it from SketchUp in one of the following supported formats:

• IFC (.ifc) - recommended
• FBX (.fbx)

See Converting from SketchUp for more info.

DWG

cmBuilder does not currently support importing vector-based CAD files.

You can convert to a PDF and import as a Drawing.

OBJ

OBJ files are a common export by drone scanning software.

To bring drone scans into cmBuilder, it is suggested to export as FBX, or convert to FBX using another software like Blender. Learn more here.

NWF

Navisworks File Set (NWF) is a master project file, and does not contain any files itself. To bring in the files you need, you must find the file that the NWF is referring to (like NWC, RVT, etc.).

Imported Model is Empty

This error usually means the system could not find valid 3D geometry in the file. Follow the steps below to confirm the model contains solids and was exported correctly.

• Open the model in its native software or another model viewer and confirm that the file loads correctly and that it contains solid geometry, not just lines or surfaces.
• For IFC files, use a viewer such as BIMvision to verify that the file opens and includes solids.
• For Revit cloud models, check whether the correct views have been set up and published, as missing published views can affect exports.
• For IFC files received from external companies that result in this error, try converting the IFC to FBX using Navisworks, then import the FBX instead. This can resolve issues caused by incomplete or incompatible IFC geometry.

The File is an Invalid Format

Make sure the file is actually a supported BIM format and not just a renamed file extension. For example, a file renamed to .ifc without being properly exported as an IFC file will fail to import. Re-export the file from the original software using the proper export settings.

Trouble Converting your File

Most models convert in 5 minutes or less. If the conversion takes much longer, there may be an issue with the model, internet connection, or our model conversion service.

The problem may occur due to the complexity of the model.

Check the following:

• Has the model already been split (architecture vs. structure)? See our tutorial: Preparing BIM Models for Import
• Refer to the export guides for common BIM software in this section
• If your model is in .nwd, .nwc, or .rvt format and you experience issues during import, we recommend exporting it to .ifc, filtering the model to include only the relevant elements, and then attempting the import again.

Still Having Issues? 

Please contact us via our chat.

To help us investigate the issue faster, please provide the following:

• File type being imported (.ifc, .rvt, .nwc/.nwd, .fbx, .stp)
• Software the file was exported from (Revit, Navisworks, Recap, Blender, etc.)
• File size