Ceilings Unexpectedly move due to wall movements.

[j_h_son]

How do ceilings and walls interact?
I have a low height wall underneath a ceiling. They are not physically touching but aligned. Not contrained. Yet when I moveor adjust the wall, the ceiling boundary changes without my consent? What's going on? How can I control this?

[dlpdi5b]

Create the ceiling first, dimension the "floating" edges in the ceiling sketch, and lock the dimensions; align and lock the edges that connect to tall walls. Then create the low walls, and you should be able to move the low walls independently.