It would be useful to have a little more control over the glazing used in window objects.
I.e. double glazing, triple glazing.
This is usually not too big of an issue as the sort of scale these windows are viewed at, its generally OK to treat the glazing as one object.
However we are currently working on a project with a recording studio, which has very high acoustic requirements - to achieve this there is a significant gap between each layer of glazing (300mm in this case!) which we would like to see in our drawings.