With Autodesk® Navisworks® being utilized more and more often in the AEC community, the various file formats associated with Navisworks® generate questions as to the usage of each format.
Navisworks® file formats are:
NWF
This is considered the project file and is the file that you will open each time when you want to perform analysis, 4D scheduling, animations, etc. No actual model geometry is saved with this file, but it does contain Navisworks® information such as review markups, saved viewpoints, and materials. It also points to the original files that are appended (loaded/linked) into Navisworks® and reloads each of the referenced files when the NWF is opened. Any changes to the referenced original appended files will automatically be displayed in the NWF file.
This file will typically be small in file size.
NWD
This file is basically a photograph of the NWF at a specific point in time. You publish the NWF file to NWD format and all of the appended (linked) files are “bound” into the NWD file. Besides the “bound” information of 3D model geometry, it also contains all the Navisworks®-specific information that was included in the NWF. The NWD allows you to share the information with someone else without being required to send all of the referenced files. Creating an NWD file is somewhat similar to creating a 3D DWF file to share in a static format.
A person only needs the free Navisworks® Freedom software to view the NWD file, although the file can be opened with any of the Navisworks® products.
The NWD file size is not as large as might be expected, as the data is compressed during the process of creating the NWD. It will be a larger file size than the associated NWF file.
NWC
These are considered cache files and will speed up access to commonly used files. When you open or append a native CAD file to Navisworks®, a cache file with the .nwc extension is created in the same folder with the same name as the original CAD file. NWC files are to be considered reference files and not working files.
NWC files are also created through exporting from Revit® and AutoCAD® so that you can share a copy of the original file without sending the actual file to the recipient. This file can then be opened or appended into Navisworks®.
See a related blog post about Navisworks Exporter for BIM Models.
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