Where is the area parameter of a sloped glazing

[AP23]

I've noticed that sloped glazing roofs don't have an area parameter. So when I shedule it, i get 0 in the area column. Changing the sloped glazing to a basic roof gives you the area but it's not real alternative for scheduling. When you schedule the panels and ad the totals, it may come close, but also not a good alternative. Any ideas?

[Duncan Lithgow]

There's some ideas here: http://www.revitforum.org/architecture-general-revit-questions/4634-calculate-roof-area-slope-glazing-roof.html

Basically you'll need to schedule the panels, and if some of them are windows that can get messy.