I’ve had several clients ask about creating a Plumbing schematic in Vectorworks, especially one that shows an isometric view of the plumbing. I know that most people are not plumbing installers, but we often have to show a plumbing schematic that complies with the building code, even if the plumber builds it differently on site.
For single story buildings it does not seem necessary to create a model of the plumbing, but a multi-story building is different, and local authorities that have to approve the your building permit drawings often have trouble understanding the drawings. A plumbing schematic can really help out.