How to correctly model this meshes sharing edges, and Subsurf?

I’m surprised myself that I have not run into this problem before.
How should I correctly model this ?:

So when after applying Subdivision Surface Modifier and perhaps Solidify Modifier, make these imperfections do not appear.

Is it possible to achieve this in these flat meshes using Crease edges or some other technique?
Or I would have to model a mesh representing a volume from scratch (rather than a flat mesh)?

How should I correctly model this ?:

(A “Non-Manifold” mesh) shows a very simple example of a “Non-Manifold” mesh. In general a non-manifold mesh occurs when you have internal faces or edges that are unexpectedly open.A non-manifold mesh is not a problem for conventional meshes, but can give rise to ugly artifacts when subsurfed. Also, it does not allow decimation, so it is better to avoid them as much as possible.To locate the non-Manifold components, you can be in either Vertex Select mode or Edge Select mode and deselect all vertices. Now, either go to Select » Non Manifold or hitCtrlAlt⇧ ShiftM. Sometimes, it can take some clever work to make these areas Manifold, but with determination and creativity you will be able to figure it out. Sometimes it is only a matter of Removing Doubles (W,R) or of manually merging some vertices (AltM).


You can disconnect the edges at the intersection

you got edges with more then 2 faces

meaning non manifold !

happy bl

Thanks to both of you. I will research about resolving Non-Manifold meshes.

Richard, you mean Edge Split, then bridge the loops of the outer mesh, and finally reduce slightly the size of the internal mesh to avoid intersection?. Or is there another one step solution?

Ok, remove doubles is easier than manually bridge the loops. But I do not know if there is some tool to do this in one step. I’ll see if Rip or Rip Fill (I’ve never used them) are useful for this.