Displacement causing detached faces I'm trying to make a simple brick texture for this archway I made, and I want to use displacement in my material. Problem is that when I attach the displacement, the faces all become detached from each other.  It doesn't seem to recognize that the faces are attached and so there's big gaps in the corners. What could be causing this? I tested the same material on a basic cube and it worked fine so the problem must be with my mesh but I have no idea what the problem could be. 

It's hard to tell on a still pic but here's what I mean by the detached faces (I made the scale high for the pic so it's easier to see).
Strangely, contrary to this answer, you need to disable auto-smooth to get rid of the gaps.



Also, add a solidify modifier, before the subdivision surface:



Result: