Compressing a .rvt

[damcclellan52Z5M]

   I know that not all files compress the same. Never zip a .rvt before until today. Had a user claim it was not zipping at all. I found it was zipping just not by much. Unzipped we had a project take up 408mb and when zipped it went down to 384mb. I did a few zips on different project/Revit program releases and it seemed to only compress less then 1/4 then it originally was. I used windows default zip and 7 zip and they all compressed the same. 

   I take it this is normal or am I missing something? Is there a better way to make it smaller?

[HVAC-Novice · Accepted solution]

Zipping basically just removes useless information. For example in a picture you have a cluster of pixels of the same color, instead of storing each pixel, it will create an information that has the location and how many pixels of the same color. That is how jpg etc. works.

I'm sure someone can explain that better. Or imagine a movie in 4K. If for a whole second the scene doesn't change, you don't need to store all 30 frames. and for following frames you only need to store the changes. 

if you have a word document as doc, it will be larger than the same document saved as docx typically will be smaller. it will contain the same information (font,, tabs, text etc.), but in a more efficient way.

If you have a file format that already is efficient and removed lot of the redundant data, zipping won't gain much. Same is true for PDF. Unless you want to lose actual information, you only can compress so much. You also can't zip a zip over an dover till you have 1 byte 🙂

So what you see is the physical limit of zip and shows Revit already does a good job compressing. 

[RobDraw · Accepted solution]

Yeah, not much to gain when compressing Revit files. If you're truly concerned about file size, you might get more mileage by deleting extraneous content but depending on your modeling environment and what is being done with these files after unzipping, this could be undesirable if there's a chance deleted content is needed in the future. 

[damcclellan52Z5M]

@HVAC-Novice @RobDraw 

Thanks guys!

[RobDraw]

Welcome!

[iainsavage]

You can do a “Save As...” and under the options select Compact File.

• Compact File. Reduces file sizes when saving workset-enabled files. During a normal save, Revit only writes new and changed elements to the existing files. This can cause files to become large, but it increases the speed of the save operation. The compacting process rewrites the entire file and removes obsolete parts to save space. Because it takes more time than a normal save, use the compact option when the workflow can be interrupted.”

[damcclellan52Z5M]

@iainsavage  

Thanks, I'll pass this along!