As the nation struggles to shrug off the worst housing crash since the Great Depression, it may be hard to believe a housing shortage could be on its way.

The nation is simply not building enough homes to keep up with potential demand. Just 672,000 new homes were started in April, less than half the long-term run rate needed to meet the nation's natural population growth.

"It is ironic, but there is a growing consensus that there may be a new housing shortage coming," said James Gaines, a real estate economist with Texas A&M.

So far, the shortfall has been masked by a weak economy that has put a damper on homebuying.

Once the job market rebounds, however, people will look to have their own homes again. This pent-up demand could get unleashed on unprepared markets, causing shortages and rising local prices.

Household formation -- the technical term for people moving in together -- has been on hold during the past few years as young people, especially, have been unable to find jobs. In the past, an average of more than 1.3 million households were formed each year, causing demand for 1.5 million new homes. (More homes than households are needed to replace those destroyed by fires, floods, teardowns and neglect.)