Talk:Builder's Hut/@comment-64.132.37.66-20130621163739/@comment-2170536-20130621164137

Neither actually. Once you buy a building (regardless if it costs gold, elixir or gems) it is yours forever. If it is destroyed in battle, it will repair itself in a short time (several seconds) once you log in. Builders that are currently working on a project are completely unaffected by an attack, and will continue hammering on the ruins once the attack is over.

Even if you are attacked a second time before you log in, the Builder's Hut will be restored (attackers never see damage from a previous attack, only tombstones).