You can define your object for ex. "Bombable" or "Barrier" in the Terrain Editor.
The Host or CM can adjust the hardness off the objects in the game, so he must only know which objects are set to which type.
Using different definitions to different object types gives the CM more options to make his hardness adjustments for ex. so high, that it needs impossible amount of bombs to destroy.
I think that every object in the AH are destroyable, so you should use this way.
