Line based family automatically joining

[t1.shep]

I hope this is an easy one...
I created a line based generic family. I draw the family in elevation so that it is a vertical extrusion. If I copy that and move it above the existing family I just placed, they will automatically join (like walls). I need a gap between them of 1/4". Why do they join together, and why can't I unjoin them?
If I draw a separate one (instead of copy) it seems to work.

Any thoughts?

[hworrell]

Old post...many versions later - but did you find a solution to this?