They didn't. They would recycle materials and make new buildings out of old ones or change the purpose of a building to a new one. They would also heavily use wood in building houses and things like that because it was available and was not that difficult to manage unlike stone.
According to the doctrine of separation of powers, the U.S. Constitution distributed the power of the federal government among these three branches, and built a system of checks and balances to ensure that no one branch could become too powerful.
Louis's Answer: The Bulge
Take care and have a good one