How to add thickness symmetrically using the Solidify modifier I have a mesh surface which I'd like to add some thickness to using the Solidify modifier, however, it only adds thickness to one side. 

I've tried setting the mode to "Complex" but I can't find a way to add an even amount of thickness on both sides.

I also tried adding a second Solid modifier and flipped normals, but this didn't work either.
In the modifier options there's offset that can be &#0177;1 or 0. The first two add thickness either outside or inside. Setting this to zero gives the result you want. Still, you must remember in this case you add half the value to either side.