Nah, there are specific beam sizes EG a 250UB40 may have the following sizes:
Depth 250
Width 146
Flange 6
Web 4
etc etc
There are basically three methods for using beams that I can see.
The Steel section tool
(you can get a perfect section including correct web and flanges sizes, but you cant give it any depth so is only usful for details)
The Framing member tool
(you can get a solid rectangular beam which you can control its line styles/dashes in 3D and in plans, but unable to get a good section)
Extrude what you want
Extrusions would be the perfect tool, except you cant control the line styles, so you cant show a beam dashed)
Is there any plans to make it possible to dash extrusions?