'broken' surfaces/mesh when rendering

Hi all!

I get this when rendering with Blender internal, there is another surface close behind that shows through in several places. This happens mostly with thinner objects further away from the camera.

Thanks for any help.


it looks like you have duplicated objects or faces there, it’s called z-fighting. try selecting all and W -> Remove Doubles in Edit Mode, or seeing if there’s a duplicate object

Also be certain that the surface-normals are all facing the same way, “toward the camera.”

also try moving the bookcase away from the wall slightly. The Z fighting issue is caused when two flat surfaces are at exactly the same place and the same distance from the camera; this confuses blender and it cant decide which one SHOULD be in front so you get the results shown here. One or more of the hints mentioned should clear that up.

Thanks for the help!
I did place the bookcase very to the wall. There might have been a scaling problem too as I had set the Scene units scale to 0.001 (Sketchup import) instead of scaling the objects.
I solved it by moving the faces away from each other, but I think the scaling might have had something to do with it.

nods that might have been a precision error to boot. Basicly you scaled down so small that as the render engine did its thing the math might have rounded non 0 values down to 0