Shooting from a roof that has walls below it doesn't really work?

[ondrej008]

Red lines are lines where you cannot shoot into that area.
The bullets hit the wall under the roof (which happens to be a wooden wall in this case).

Expected behaviour: bullets fly past the walls and onto the open ground thus making the roof useful.
Map is Sorokyne Strata.

 

[ondrej008]

Alternatively the walls should obscure vision since they block bullets.