Model Efficiently

Minimize unnecessary geometry, views, and elements when designing your model.

The size of a Revit file can often be affected by a number of attributes that are likely unnecessary to your model. The following considerations will help trim the size of your model.

• Always leverage the team understanding of typical 2D drawing conventions to invest the correct level of model complexity. For example, minimize geometric detail that cannot be seen at the chosen output scale. The necessary level of detail can be conveyed in terms of a commonly understood drawing scale. Balance this with the need to allow the model to provide design intent without explanation. Also, consider the appearance in renderings and video. 

• Use generic versions of elements until the type construction is determined. Unless material use or other types of analysis will be applied to the model, generic models incorporate less geometry and are sufficient for many projects.

• In large-scale projects, break up the model into multiple files of about 200 - 500 MB and link together the resulting project files. This works best if you can work on one file while the other links are unloaded for a majority of the time. However, engineering consumers of architectural models may have to maintain one or more constantly loaded links, which may affect model size estimation and thresholds for those disciplines.

• When creating detail views, model hatches with filled regions, not lines.

• Limit joined geometry to necessities.

• Avoid maintaining unnecessary groups. Delete unused groups from the Project Browser.

• Regularly review and fix warnings.

• Use arrays to copy and associate objects together. After an array deploys, ungroup the arrayed objects to remove their parametric associations. Alternatively, you can deselect Group And Associate in the Options bar when you create the array.

Performance Considerations when Importing and Linking Files

Use linked or imported files sparingly.

Consider the following best practices when linking or importing files into your design:

• Unload links of all types if not used. Temporarily unload links if not needed in the view and reload them as required. This strategy limits the memory resources necessary to open the file.

• Importing a file on a network may improve performance rather than linking to the file.

• Revit links must be in same version.

• Large projects may benefit from breaking a model into separate project files, assigning them to a workset, and linking them into a single central file. 

• When importing DWG files:

  • Minimize the number linked or imported DWG files in your model.

  • Avoid importing unnecessary data like hatching or AutoCAD-specific linework such as construction lines. Delete unnecessary parts and layers of the DWG file in AutoCAD and import a much smaller file.

  • Avoid exploding imported geometry which changes a DWG from a single managed element to hundreds or thousands of additional elements, depending on the number of items in the file. Increasing the numbers of elements affects regeneration, manipulation, and view refresh time.

  • Only link essential DWG files into views. Unlink files that are not necessary.

  • Switch off the visibility of 2D AutoCAD DWGs in perpendicular views. 2D AutoCAD files linked into a plan view show as collinear lines in elevation and lead to performance degradation.

• Raster Images:

  • Remove unneeded raster images and renderings because they represent a performance and file size cost.

  • Save black and white raster images as 1 bit per pixel format instead of JPG or TIF. MS Paint refers to this format as Monochrome Bitmap.

  • Large raster images, such as logos scaled down to fit into title blocks, will still retain the original file size. Consider creating a smaller, simplified image for import into Revit.

Project Views and Performance

Configure project views to optimize revit performance.

Consider the following best practices for managing views in your project.

• To improve performance when opening the project, set a drafting view with few if any elements as the starting view.

• Minimize view depth where possible in elevation, plan, and section views so that geometry hidden by other elements in the view does not affect the view drawing performance. 

• Consider back-clipping views to reduce the quantity of geometry maintained in a view. Often the overhead associated with additional object cutting due to back clipping is more than offset by the resulting reduced geometry maintenance.

• Use section boxes to limit visible geometry when working in a 3D view. 

• Minimize the number of views in a project to reduce model size. Likewise, consider deleting as many views as possible from static models linked into the model.

• Use Wireframe or Shading display styles when working in a linked file environment.

• Avoid hiding large quantities of individual elements in views.

• Turn off unnecessary categories in Visibility/Graphics and templates. 

• Close unnecessary views.

  • When working in a 3D view, most of the file is placed into RAM. These views should be closed when saving to central, because Revit will update this complex view as part of the save process.

  • Although Revit is optimized to update only views that are visible or become visible to the user, you can close inactive views to recover memory allocated to those views.

• Assign the proper level of visual detail to a given view. In a 1/8" plan view, assigning a Fine level of display detail may be unnecessary. Plan views with fine and medium detail level are slow to open if there are many wall join layers to route. Use a Coarse view setting unless you need to show greater detail. 

• Unless necessary, turn off shadows in views and before printing. 

• Use the Draw visible elements only graphics setting to reduce the amount of information drawn during view navigation. This will also optimize the speed when panning, zooming, and orbiting the model.

Worksets and Performance

Consider the following recommendations:

• Worksets help to manage element visibility and reduce visual clutter during editing. Closing unneeded worksets releases allocated RAM for use in Revit.

• Put links and imports into individual worksets and close the worksets when not in use.

• Use selective workset opening when opening a workshared project file.

• Close worksets not required for a given editing session.

Worksharing Performance

Leverage team communication to optimize Revit performance.

Communicating efficiently in workshared models can reduce unnecessary interruption to team workflow.

• Any large project requires constant team coordination. Many teams have adopted instant messaging (IM) software to help coordinate model editing and saving between geographically dispersed teams. Likewise, Revit Cloud Worksharing is useful. See About Revit Cloud Worksharing.

• When making significant changes in a project, such as moving a level, perform the operation when no other users are working on the file. Be sure all elements are relinquished. When the changes are complete, ask all users to make new local files.

• Sync with Central operations can be accelerated by a preceding Reload Latest command.

• When a project is edited by other users for a day or more, it may be faster to create a new local model from the central model rather than relying on Reload Latest to update the individual local model a day or more behind the remainder of the team.

• Attempt to keep project team workstation specifications equivalent. A dramatically weaker machine specification used by a single team member can reduce overall project performance.

• Revit saves only one local model at a time to the central file. As deadlines approach and the frequency of saving to central increases, use the Worksharing Monitor add-in to coordinate Save to Central operations across the team. Alternatively, team members can stagger their regular saves to the central model by either communicating an intention to Save to Central to the team or by assigning a standard saving time to each team member, for example, at ten or fifteen minutes after the hour.

• When attempts to Sync with Central collide, a dialog notifies that another user is currently saving to central. Canceling the Sync with Central operation will prevent queuing the save request, allowing the user to continue to edit the local file before attempting another Sync with Central command.

• Revit attempts to update all open views before saving, so both local saves and saving to central will increase in performance if a simple view, such as a drafting view, is the only view open when the save operation begins.

• To reduce disk usage, regularly compact central and local files.

Brokaw's Jam

• Periodically open the file with Audit selected (If the file is workshared, Select Audit and Detach from Central).

• Delete all views not on sheets.

• Delete any AutoCAD imports and use them in a separate linked model where they are imported and converted to Revit elements and cleaned.

• Purge unused.

• Review and resolve warnings (as many as possible). Excessive warnings can increase file size and greatly impact performance.

• Save the file with compact selected (if saving over the same file). If this is a workshared file, it's recommended that you archive the original central file and its backup folder before saving in the same location with the same name.

• Save the file with a new name: Compact will automatically be selected and this will compact the file further than just selecting compact.