I have one 3d poly that goes around the bldg. pad and then garages, entrances and stoops.
IF it is already at desired design elevations
select and ADD to Surface as Break Line....
Otherwise...use get elevations from surface feature in the elevation editor for the feature line....
to make it dynamic to a surface/profile there is a way to connect it to a corridor...it's and abstract method
falls into advanced use
*and I'm still not totally sure what your end goal is?
is this for ONE building or for many building with similar footprint and grading design?