By Garry Stockton
Revit to Navisworks conversion can be done in two ways, either exporting from Revit, where you will create and save a NWC file from your Revit Model, or by opening the Revit file with Navisworks, which will also create and save the NWC in the same location as the Revit file and then will add it to the NWF model. Either way, it is important to prepare the model before converting to Navisworks.
Preparing the model for conversion
If you are intending to use 4D planning as a BIM use in Navis, model elements must be subdivided in relation to the construction planning tasks.
”Parts” tool in Revit can be of help to segment an element in smaller pieces. For instance, you can model a retaining wall in Revit for all its length, but for construction purposes and planning, it must be broken down in smaller pieces that can be assigned, for example, to different days or construction periods.
Ensure that the coordinates of the model are correct. Navisworks allows the assembly of several models, to do so it is imperative that the shared coordinates are properly set. Relocating models once loaded in Navisworks is possible, but not a great idea.
Prepare a dedicated view for model export and name according to your BIM plan. If the view name contains the string “navis” then the translator can use it as the default Navisworks view and you can save a lot of time as Navis can locate the view for you automatically and there is no need to make the export manually from Revit.
Model export is made from a view. The translator converts only what appears in that view. Categories that are not relevant to the use of the model in Navis should not be exported. We also recommend you hide the links in the Navis view as those should be exported independently and assembled later.
Note: Make sure the right level of detail is chosen.
Creating the NWC from Revit
With the Naviswork installation, a new plugin will show up in your tools ribbon. Go to Add-ins - External Tools -Navisworks.
A new window will show up asking for the destination folder of the file. In the bottom part of this window, you can access the Navisworks settings.
- Convert construction parts to export the parts instead of the original element.
- Convert element properties should most of the times be checked unless you’re not interested in accessing the parameters of each object in Navisworks.
- Convert linked files should, most of the time, be unchecked, as we recommend exporting each link separately and assembling them in Navisworks.
- Convert room as attribute to include the room properties in doors, windows, fixtures and other items.
- Divide file into levels will assign objects to levels, most of the time in the right way, but sometimes we might encounter elements assigned to the wrong level (roofs, staircases, beams) or hard to assign to one unique level (multi-level walls).
- Export from Revit will make the most sense from the Current View so make sure you’re in a 3D view with the information and level of detail you want.
- Export room geometry will create solids with properties for each room. Must have Export Entire Project in order to work.
- Faceting factor tells how many triangles we want, 1 being the default value. Keep the faceting as low as possible for your purposes.
Part 2 to follow