You may have noticed that by default, web joist display will be controlled by the Structural Framing > Web Joists subcategory, regardless of what the Structural Usage is set to. But what if you want to override the display by Structural Usage, like other framing members are displayed?
Let's look at the following example comparing display behavior between a Wide Flange and K-Series web joist:
I set the following display overrides to help illustrate the behavior:
After setting the overrides, you'll see that the K-Series members always display according to the Web Joist subcategory, regardless of their Structural Usage.
If you want the K-Series to display according to Structural Usage, as the Wide Flange does, you can do the following:
Edit the K-Series family. In 3D, select the line used to represent the top chord. In its Properties, change the Subcategory to <Defined by instance>.
Reload the family back into the project. You'll see that the element display is now controlled by the Structural Usage setting.