In the wake of the Great Recession, lots of those millennials have been stuck either staying at home, or moving back in with their parents. As economic conditions improve, they will become more likely to strike out on their own:
That process of venturing out and forming new households may have already begun. There has been a spike recently in the rate of household formation.
Read more: http://www.businessinsider.com/us-housing-market-2015-2#ixzz3UWaUMXXB