It isn't the retirement George Warren dreamed of.

Confined to a wheelchair and living on disability payments after losing his job, Warren, 63, figures he would be homeless in old age if not for a senior housing program offered by Catholic Charities of Maryland.

"I had plans, but life had other plans for me," he says.

Warren worked for decades, starting with a "sophisticated lemonade stand" he opened with friends at age 9. He paid into Social Security as he meandered through a half-dozen jobs in telecommunications and networking. But he lost his last job in what he calls an age-related layoff. And his income on disability isn't enough to cover his expenses.

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So Catholic Charities gave him a place to live at Village Crossroads near Baltimore, which receives funding from the U.S. Department of Housing and Urban Development.

In the aftermath of the Great Recession, millions of Americans are in a similar situation — or at risk of it. Many never saved enough to begin with, then lost their jobs or saw their wages stagnate when the economy collapsed.

The result is that Americans are at least $6.8 trillion short of what they need to have saved for a comfortable retirement, according to the National Institute on Retirement Security. For those on the eve of retirement — ages 55 to 64 — the shortfall comes to $113,000 per household.

Retirement experts worry that many will require extra government help in old age — the kind of services Village Crossroads provides.

Helen Hatchell couldn't walk when she moved into Village Crossroads in July. Hatchell, a widow who cleaned office buildings before retiring and is now entirely dependent on Social Security, underwent a series of operations. Now, she can get around on her own and keeps herself busy by sewing.

"You gotta live or you gotta die," she says, "and I wanna live."