the floor is seen through the walls
One way, in your case, is to just lower the camera far clip. It defaults to 100. So scale the floor plane up a bit and pull down the camera clipping end.
Attachments
26_edge_camera_clip.blend (81.6 KB)
hmmm i didnt think about that… it might work 
If it worked for me, a total noob. It should be able to work for you.
Or you could just make sure the edge rendering scene only includes that which you want to be processed with edge rendering…