Right now we are using Maya to make our 3D models and when we import them to UDK, our walls are completely hollow. When we go to fracture the mesh we have hollow walls and the model and fracturing don't work well together. The walls have the same dimensions and orientation when we made the model, there is a very thin wall with space and the other side of the wall. it's almost looking at this | | . So I am asking what are we doing wrong that makes our walls hollow when we import them into UDK? Can we just reimport our models or do we have to rebuild all of the models from scratch?