Customize label property modifiers for joist or beams to include length, quantity and/or spacing for ease of identification in the field.
Example: Add rounded length followed by an apostrophe ‘ to indicate feet. ( Or add "Ft." instead.)
Open Job Properties - Navigate to File > Setup > Job Properties > Labels > [preferred member type], or right-click in the white space and select Job Properties from the menu and follow the navigation steps above. The following example is for Floor Joists, just as we've displayed in the image above.
To access the Template Builder, click into the Template field and click the button with three dots. 
In the Template Builder select the modifier to be added to labels. Double click from the list of Modifiers and the Modifier will be added to the template below. Between Modifiers plain text will be displayed just as it's typed.
Click OK and then Apply in Job Properties and the changes should be immediate.
NOTE: The example above would need to be managed per job. The same general steps can be taken in Manage Job Defaults, by modifying the labeling Scheme used by a designer's preferred Template(s).