1 building per ward would give a hella lot more rooms than probably there is players on each server anyway so seems unlikely. Its very probable that the building is a ward on itself which will give this upgrade.

Still not good enough. I still can`t understand how everysingle MMORPG out there can handle housing better than XIV considering they have much lower budget... Or do they? Maybe this is just all proof that SE isn`t supporting this game anymore and they are working on a very limiting budget.