How to Keep Revit Family file sizes small

Revit Family file size is an often-discussed topic with many people feeling very passionately that file size should be kept at a bare minimum with the common recommended file size being under 1MB.  While it is true that large file sizes can be an indication of poor modeling and poor model performance.  It’s not always the case that a large file size equals a bad family. A well-constructed 8MB family may outperform a poorly built 800KB counterpart. The point of this article is not to fuel a hyper fixation on family file size, but rather to help you troubleshoot a family which is both large in file size and performing poorly.

The following are best practices that you can employ to not only reduce file size, but to help improve a Revit Family file’s performance:

1. Remove imported AutoCAD, SAT, and image files.
2. Run the purge command on the family and any nested families being used.
3. Remove unused materials.
4. Use only native Autodesk Revit geometry. (Avoid SAT and other foreign geometry files.)
5. Minimize voids where possible.
6. Use nesting only when necessary and to avoid arraying where possible.
7. Avoid multiple layers of nesting where possible. (The more your family looks like a Russian nesting doll the more computing resources it will require.)
8. Check for duplicated geometry in nested families.
9. Avoid grouping geometry, as it inflates file size.
10. After creating the file, compact its size by performing a ‘Save-As.’
11. You may also find that closing the file and re-opening it with the “Audit” box checked can help further reduce your file size.
12. If your family file was worked on for a long time and went through many save iterations it will have a save history that is also bulking up the file size.  In this case you may try loading it into a project and then saving it back out.  Doing this removes all the unnecessary history information as well as embedded materials which can reduce the file size significantly.

For further size reduction, load the family into a project and save it from the project file. This step can cut up to 30% or even 45% of the file size, eliminating unnecessary historical data accumulated during prolonged work on the RFA file. Note that this process removes embedded materials, requiring a separate Autodesk material library if materials are necessary for the content.

By adhering to these guidelines, one can optimize Autodesk Revit family files for technical audiences, ensuring efficient project performance and successful integration.