Eg. The government coming round and saying "this isn't up to spec for [energy efficiency, fire safety, future housing requirements], it needs to be torn down and rebuilt".
The way to defend against that is to make it a building of historical importance, so that rules or exceptions are written specifically for it.
So my 1000 year building will be a massive artpiece, cathedral, or something along those lines.
As soon as you get famous enough, it doesn't matter what materials your building is made of, it will end up being maintained.