Hi all,
Revit projects are undeniably large. We're talking about 30 MB at least for a small office building, while all we need to extract are floor plans, elevations, a section and an artist's impression.
There are many aspects that contribute to the file size, so there must (or should) be many ways to decrease file size.
This topic is intended as a knowledge base, up-to-date with Revit Architecture 2008. I'll post what I know as a proven and used fact, and you are next until we have gathered enough facts to decrease the usual final project size with 50% or more.
Temp files - Revit saves a backup file when saving. This is a failsafe for errors during saving. If the process may fail and the file gets damaged you at least have the previous version to work with.
Saves: 90 to 100% of the project file size for each deleted backup file.
The Undo log - when you specify 'save as' instead of simply click the disk icon, Revit creates a new file without the Undo history. This Undo-file makes for more or less than 10% of the total file size. We have yet to determine how long or big the Undo history is for typical Revit-projects.
Saves: 2 to 30% of the project file size, depending on the effectiveness of the work flow. Lots of trial&error seems to make for a big undo file.
I have left the most obvious answers for grabs, simply beause I don't really know how to define them best. If I'm at error on certain points please let me know and I'll make adjustments in red Italic print.