How to non-destructively solidify only certain faces? Sometimes I would like to solidify only certain parts of a mesh.  I know I can use the solidify under the faces (Ctrl+F) menu, but often I would like to do it in a non-destructive manner using the solidify modifier.

The solidify modifier does have an option to solidify only a particular vertex group.  However when I use this option it solidifies (i.e. duplicates) the entire mesh, but only moves out the vertices which are in the vertex group leaving the areas not in the vertex group with double overlapping geometry.  This results in a giant hideous z-fighting mess, as shown below.



So can I have the solidify modifier apply only to the vertex group and not create this mess?
There are really two ways of handling this issue.

1) As Denis suggested in the comments, check Only Rim. This won't give you thickness, but will just displace the faces in the vertex group.

2) Offset the Factor a small amount: