Projectiles trough Walls

[Thalariuz]

Hello, i got a problem in a map im making
Im making a house on my map, using cityscape walls,and a door.
But when i play it on b.net people seem to abuse it when using ranged units.

Archers etc standing in there and can shoot all troops outside, "trough the walls". wich is kinda unrealistic :/

I have tried using pathing blockers but doesnt seem to work.
Any of u guys know what to do? to prevent long ranged units to shoot trough walls and doors?
plz need help ^^

 

[Thalariuz]

no one can help`??

 

[Darg]

only way I can think of is to use line of sight blockers so they can't see through the wall. If they can't see it, they can't shoot at it.