2 sided height map issue

Hi
i am using a heightmap on a 2 sided shader on the outside it looks fine(outside faces) but inside it is a mess are height maps only feasable with single sided shaders?

 

Screenshot of the problem would be helpful...

One Problem with 2-sided shaders: they are always going to produce wrong lighting on the backfacing sides of the mesh. The back will always have the same shading as the front (because it doesn't have its own vertex normals). If you want consistent shading, you will need to actually have a two-sided mesh.

But witout further information I don't know if that is the issue you encountered.

 

Actually, if you define the "VFACE" pixel shader input semantic, you can use that value to check to which side the pixel belongs and flip the normals accordingly. I don't know if it's possible to use that in surface shaders, though.