You are assuming that demand for housing per capita is some kind of constant. It is not. It is affected by price and by consumer choice, including inter alia, the increasing demand for second homes. In any event, the supply and demand clears. It is not as if there are tons of empty homes out there.
==It is not as if there are tons of empty homes out there.
Actually, if the following assessment is correct, there are indeed a ton of empty homes out there.
http://www.financialsense.com/fsu/editorials/2005/0731.html