An NWF file is an Autodesk Navisworks File Set, commonly used in construction, architecture, engineering, and BIM coordination. It works more like a project setup or coordination workspace rather than a complete 3D model file. An NWF file usually does not contain all the actual model geometry inside it. Instead, it references or links to other source files such as Revit files, DWG drawings, IFC files, or NWC cache files. This means the NWF file tells Navisworks which model files to load and how they should be organized in the project.

The NWF file can store important project information such as saved viewpoints, section cuts, clash detection settings, markups, comments, appearance overrides, and review settings. For example, if a project includes separate architecture, structure, and MEP files, the NWF file can bring them together in one Navisworks workspace. However, the actual model data usually remains in the original linked files. Because of this, if someone sends only the NWF file without the linked source files, the model may not open correctly, or Navisworks may show missing file errors.

This is different from an NWD file, which is a published or packaged Navisworks file. An NWD is more like a snapshot of the model at the time it was created. It contains the model data needed for viewing, so it is much better for sharing with clients, contractors, or reviewers. A simple way to understand the difference is that an NWF is the working coordination file, while an NWD is the finished shareable file. The NWF is useful while the project is still being updated and coordinated, while the NWD is better when you want to send someone a stable version of the model for review.

An NWF file usually contains the coordination information that tells Autodesk Navisworks how to assemble and display a project model. It does not normally store the full 3D model geometry inside the file. Instead, NWF file opener keeps references to the original source files, such as Revit, AutoCAD DWG, IFC, or NWC files. In other words, the NWF file remembers which files were added to the Navisworks project and where those files are located, so Navisworks can reload them when the project is opened again.

The NWF can also contain saved viewpoints, which are specific camera angles or model views that users can return to later. These are useful when reviewing certain areas of a building, such as a mechanical room, ceiling space, lobby, or structural connection. It may also store section cuts, which allow users to slice through the model visually and inspect the inside of walls, floors, ceilings, or equipment spaces without changing the original model files.

Another important thing an NWF file can store is clash detection setup. For example, it can remember tests between ductwork and structural beams, plumbing and walls, or electrical conduits and ceiling systems. It can keep the clash rules, saved clash results, grouping, comments, and review status, depending on how the Navisworks project is managed. This is one of the main reasons NWF files are heavily used in BIM coordination, because project teams can keep checking for conflicts as the linked design files are updated.

An NWF file may also include markups, redlines, comments, and review notes added during coordination meetings. These notes help team members identify issues, assign corrections, or explain design concerns. It can also remember appearance overrides, such as coloring specific pipes red, hiding certain layers, making some objects transparent, or changing how different trades appear in the combined model. These display settings help make the model easier to review without modifying the original Revit, DWG, or IFC files.

In simple terms, the NWF file contains the instructions, saved views, review data, coordination settings, and links that make up the Navisworks working environment. The actual building model usually remains in the linked source files. That is why an NWF file is powerful for ongoing project coordination, but it is not always enough by itself when sharing the project with someone else.