The building I am modeling has a slightly sloped (2 degree) roof with a 2.5' tall parapet wall on 3 sides. I thought it would be as simple as adding a wall on top of the roof and then simply changing the elevations of the top of wall so that I get a 2.5' tall parapet wall but when I did this, it also changes the height of one of columns in an adjacent building. How can I change the wall elevation without changing the elevation of the column? Do you just make the wall not go to the point of the column so it doesn't think they are connected? I wish it was as simple as turning the columns off or being able to lock the columns so they can't be modified.
If the column and wall share the same plan location (column centroid, wall CL), then they always move together. When there is a step in a roof where one beam is higher and another is lower, supported at the same point, then two stories are always required to model that situation (though it may not be worth it in this case). If the column is moved off the wall CL, then it can be adjusted independently, but that opens up other potential framing issues. Our Modeling FAQ has more on this.