You need to use stairs to get pillar placements. Note they do not have stability in this way, except under rare conditions. The pillars keep people out, provide obstruction and allow light to spill in in nice ways – and you can shoot through them.
Not with all my examples does the bottom foundation cause cascade failure. But if we stick with the example you gave me, it takes 7 explosive jars to get to this point:
When the foundation is finally indeed removed, the ones above it will collapse. ^^^
If you place walls, fence foundations, ceilings and some support (a pillar in my example), the foundation block can go away completely, leaving all above intact.
