What’s the biggest threat  hanging over the head of many older Americans heading towards retirement? Unfortunately, it might be the very roof of the house that they live in, and the mortgage loan that they’re still paying.

From 2001 until 2011, the amount of seniors carrying a mortgage debt on their home into retirement rose nearly 10%, from 22% to 30%, says a new report by the Consumer Financial Protection Bureau. Unfortunately, during the same time period, the average balance that older Americans were carrying on the mortgage almost doubled, going from just over $43,000 to $79,000.

What that means is that, instead of money going towards their “next egg”, helping to pay for health care expenses and other important costs, many seniors are instead using that money to pay their mortgage bills.

Today almost 60% of the retired homeowners in the United States are spending money on mortgages, to the tune of over 30% of their household income. In fact, when you compare the housing costs of older homeowners who have a mortgage and those who don’t, the difference in monthly housing costs is nearly $800, $434 for those with no mortgage as opposed to just over $1250 for those who do.

In their report the CFPB says that “Much of the increase can be attributed to the refinancing boom of the 2000s”.   They also cite other factors including  “a general trend among Americans to buy their first home later in life, provide small down payments on home purchases, and borrow against their home equity to pay for a variety of expenses.” Even if they own their homes free and clear they still have monthly expenses like utilities, and even cheaper home security systems add up.

The fact is, senior homeownership rates have remained virtually unchanged since the recession and are among the highest of any age group in the United States at 80%. At the same time, the latest Census data shows that young consumers have seen their homeownership rates fall.

Another fact is that seniors are vulnerable to economic downturns more than any other economic group and, with much of their wealth invested into their homes, that vulnerability increases. Events like the housing crisis of 2008 actually lowered the net value of many older Americans and, according to the Censud, the median net worth that they used to have at just over $170,000 has plunged to just under $28,000.

According to a recent report by Boston College researchers, this combination of high mortgage debt along with a lack of liquid assets is creating a change in the way most seniors enter into retirement. Nearly 70% of people who still have a mortgage payment when they reach 64 are still working, compared to just 50% of those who have managed to pay off their mortgage loan.

Barbara Butrica, the author of the Boston College report, was definitely not happy with the results. “Older adults are supposed to be at the peak of their wealth accumulation and debt-free going into retirement, yet over time they have become increasingly more indebted and more leveraged,” she said.

That’s not good news for retirees, and unfortunately it’s only going to get worse.