uneven window sashes

[3Dme]

Hi All,
Can anyone suggest a way to model double-hung windows with uneven sashes?
For example, if the top sash was 24" tall, and the bottom 36" tall? (I don't see a setting in the window spec dialog for this)

[moak]

Settings are here:
Window dbx > General Tab > "Movable Size" setting

[3Dme]

thanks Kevin!