For my projects it is necessary for flat roof build ups to have a sloped element above the timber roof deck to ferry the surface water to a trough gutter. Currently I create this by having two roof composites that together make the full flat roof build-up, the first being a totally flat timber deck with OSB and plasterboard the otherside, the second being the 1 degree sloped firring, insulation and EPDM finish.
I wondered if there was a way to create a roof composite to incorporate part of the element being on a sloped angle such that this could be one composite?
This would be useful to me because this would make flat roof skylights look cleaner as I will not need to create a second opening.
Here's a workaround that might work - there is a GDL object created by a forum user Paulo that does something that comes close to what you want: a mesh object with layers. You wouldn't be able to add a skylight to it, but you could cut a hole in the mesh and add a roof as a glass or so.
The latest version of the object is in this page, the second last post. It is from 2 years ago though, so I hope it still works fine on AC25. layered mesh object - forum post