Nice work... =] Much more comprehensive then that tut in the help file for parametric joist...
Umm... Did you notice you spelled LOUVER wrong in the tut... =]
http://en.wikipedia.org/wiki/Louvre
If you made the tutorial to build that in Revit you would be a golden god... =]
And i only noticed when i did copy/paste on the formula for the Louver height and Revit TOLD me it was wrong compared to how i was spelling it (from reference)... I am horrible at spelling... =\
Thanks... =]