Interesting topic!
I prefer to use layout only for adding texts and annotations. Everything else, including hatches and dimensions, is done in SketchUp. SketchUp is more fast, more reliable, more fun and the 3d model can be opened by the client as well.
Some elements are only modeled in 3d as a simple volume and it's details are added in 2d in the sectioncut (ventilation duct, a timber framed wall).
Plugins that make the process more easy are:
ProfileBuilder by Whaat
SectionCutface by TIG
2dBoolean by Jolran
[image: WSek_section.jpg]
[image: 7odS_model.jpg]