How to make buildings invincible and prevent new structures?

[Versepelles]

1) Is there a way to make buildings invincible to both players and aliens? If so, how?

2) Is there a way to prevent players from building in certain areas, while allowing buildings to exist and operate normally in that area (think npc buildings)?

[DedlySpyder]

1) http://lua-api.factorio.com/0.13.8/LuaE ... structible (also see minable below it)

2) I think the only way is to check when a player or robot places something, and see if it is within your no building area