The All-in-One Sash Window Revit Family allows you to setup any number of vertical as well as horizontal glazing bars separate for the lower and upper sash.
The parameter to adjust the number of horizontal as well as vertical mullions (glazing bars) can be found in the type parameter of the All-in-One Sash-Window Revit Family.
The following example shows 1 vertical and 1 horizontal mullion for each sash:
The next example shows 3 vertical and 2 horizontal mullions for the top sash as well as 1 vertical and 2 horizontal mullions for the bottom sash:
Learn more about all the great features of this All-in-One Sash-Window (Double Hung Window) Family at http://www.revit-content.com/content/sash-window/