How can a house that is freshly placed become slightly worn within an hour or so? I was under the impression that you would not be able to build/acquire another one for seven days unless you took down your house, in which case you could then build (but not receive) another. But on my shard someone has been able to place a house and then seemingly almost immediately place another to set the first into decay, and not for the first time. I am probably missing something obvious here, can someone please enlighten me?