Opaque Wireframe Material

Okay, so obviously it is really easy to make a material that just shows the wire frame of an object with any colored edges. However, can I make it so that the material still blocks sight of objects behind other ones?
For example, in that image you can see the boxes behind the wall right there. I just find this odd because the material blocks sight of edges on the other side of the wall, but not the boxes behind the wall.

Sorry if this is a really dumb question, I am still learning Unreal and I have barely begun to mess with materials.