Quote Originally Posted by Captain Fishpants
No. The culture penalty from buildings comes about because they are a constant reminder of the 'good old days' before the conquerors came. If you want to eliminate cultural penalties permanently, you need to replace any buildings with a cultural mismatch.

Of course, you may not be able to do that: roads, for example, can't be demolished and many barbarian/nomad factions lack the ability to improve existing (Roman) roads.
What if I upgrade an existing Barbarian building to a Roman one, will the culture effect that building had remain?