Custom treads can be added to the stair macro. The tread types 22, 23 and 24 are used custom treads. The only difference between these tread types is the connection type to the stringer.
New treads are added using the User Sections creation tool.
To be recognized by the macro, the section class must be "User defined treads" while the section name can be any name.
Once the profile is added, it can be used by selecting the tread type 22, 23 or 24.
On the Tread dimensions 1 tab, the Tread profile size list contains the created user section (if it doesn't, you may need to restart Advance Steel).
Note: New tread sections can be added only with the User Section tool. Already existing profiles cannot be used for the stair structural element.