Getting your Revit Model back to Warp Speed, Scotty!

We ran into some issues with slow loads and regens with some of our shared Revit models recently, and decided to come up with a checklist to help you look for items that can cause a model to have these issues.Your circumstances may vary, but these should help you eliminate some performance issues.

Location of the Files

How many have servers with mapped drive letters to specific folder locations? And the locations could actually be on servers in other office locations?

When a project is loaded into Revit, the program resolves the path locations to the linked files. But if the drive letter mapping doesn't match from office to office, the program can spend an inordinate amount of time trying to locate files. This mainly occurs when drive letters are not mapped to the same server, or if the server is in a different location.

To resolve this, the first step is the use the UNC file name for the server. This can vary widely across firms, but if a server's actual name is SERVERO1, then you want to start your path like this: \\SERVER01\folder name, etc... This helps out tremendously when you have multiple office locations with a variety of servers in the firm where Revit files are stored.

This applies not only to RVT files, but also any lined DWG or image files you may include in your model.

One other option is to set the pathing to Relative, instead of absolute. If you have files stored on different locations (such as office locations, or practice based servers) and you're not planning on moving the files, then an absolute path option using a UNC name works really well. If you may need to move the project files in the future, and keep them all in the same root folder, then use relative. That way, Revit doesn't spend a lot of time searching for the linked files - instead, it will start in the same root location as the file you are opening.

Workset Control

One item that helps speed up opening a file relates to worksets in a central file. When the program opens a file that has worksets enabled, you get a dialog that asks what workset you want to open:

If you don't need to see or use items in a specific workset, select it - under the Opened column, you can change this from Yes to No by selecting the close command. Since one thing we like to do is place linked files, such as Revit or CAD files, into specific worksets that you can open and close as needed.

MEP Issues

This one popped up when we migrated a project from 2013 to 2015. Since it wasn't one we really targeted to get the systems part working correctly, we had a little spate of errors (ok, a LOT of errors) regarding pipe and duct calculations. Since we're running the R2 version with Update Release 3, I found a neat new little feature.

Under the project browser, and families, select a duct system family. Edit the Type Properties, and look for the mechanical settings:

If calculations are set to All or Flow Only, the program is constantly reviewing the duct and pipe layouts and adding sizing values. The old way was just to set this to none, but Autodesk added a Performance feature that helps even more with files have large networks. The details are a bit long, so here's a link to the actual help file.

Another item you can control lives on the Analyze tab. The Check Systems tools for duct, pipe, circuits and disconnects can really help you find errors. These are toggles that I turn on when I want to check, and turn them off when I'm finished. Leaving these off when you leave the file is another good idea.

The last item to check includes the Warning tool, located on the Manage Tab, Inquiry panel. This lists all errors in a file - if there's a lot, the program will be trying to track and resolve them when opening the file. Finding and fixing thse errors makes the file run much smoother, and keeps your model happy - so take the time to review these on a regular basis.

These are just a few tips - I'll add more as we discover them, but consider this your Christmas present. Enjoy the holidays!

David B.