When you consider Ys= 70mm i.e. potential of ground to heave 70mm it is clear that even complying with standards is insufficient and could lead to negative soil/paving grade toward dwelling. I have seen this many times on my pre purchase inspections with houses that have been in service 1-12 years
BE, I was thinking of what you have observed regarding the inspections and observations of negative paving towards the dwelling. If the path was tied into the slab with steel dowels, then if there was upwards movement of the paving with soil heave, the steel would anchor the paving edge to the slab edge whilst the outside of the path/apron would rise causing that negative fall towards dwelling. If on the other hand that the apron was against ableflex between it and the house with a flexible sealant then the whole apron should rise as one hopefully keeping its fall AWAY from the dwelling.