Federal Reserve Chairman Ben Bernanke on Thursday called for additional measures to stem the rising number of mortgage defaults, stressing that home foreclosures have played a central role in the ongoing financial crisis.

Housing advocates for months have expressed skepticism that existing programs are enough to help.

Forces working against these measures include home values that have yet to reach a bottom, rising unemployment figures, and the difficulties inherent to renegotiating mortgages that have changed hands many times.

Bernanke, in remarks to a Washington, D.C., conference on housing, joined the chorus calling for more.

The Fed chairman reiterated many of the steps taken so far by public and private lenders to shore up the U.S. housing market, then said it hasn’t been enough.

“Despite good-faith efforts by both the private and public sectors, the foreclosure rate remains too high, with adverse consequences for both those directly involved and for the broader economy. More needs to be done,” he said.

If trends continue, lenders will initiate 2.25 million foreclosures this year, up from an average annual pace of less than one million before the U.S. housing bubble burst in 2006.

In addition to roiling financial markets, foreclosures have taken their toll on broader society, Bernanke noted.

“Foreclosures impose large costs on families who face the loss of their homes and reduced future access to credit. But the public policy case for reducing preventable foreclosures does not rely solely on the desire to help people who are in trouble,” he said.

“Foreclosures create substantial social costs. Communities suffer when foreclosures are clustered, adding further to the downward pressure on property values. Lower property values in turn translate to lower tax revenues for local governments, and increases in the number of vacant homes can foster vandalism and crime,” he added.

To curb these problems, Bernanke offered several more options that might help reduce “preventable foreclosures.”

In no specific order, Bernanke said Congress could ease the terms of a government program called “Hope for Homeowners,” which lets distressed homeowners refinance into more affordable, federally insured mortgages if the lender agrees to write down the amount owed on the mortgage and pay an upfront insurance premium.

Bernanke suggested Congress lower lender’s upfront insurance premium, as well as reduce the interest rate borrowers pay, which currently stands at about 8%.

Another option would ease the terms of a loan-modification plan put forward by the Federal Deposit Insurance Corp. that seeks to make monthly mortgage payments more affordable.

Under the plan in place, struggling home borrowers pay interest rates of about 3% for five years. Rates are cut so that borrowers don’t pay more than 38% of their pretax income on housing. Bernanke suggested this threshold could be lowered even further with the government sharing some of the cost.

Bernanke said the government might also purchase delinquent or at-risk mortgages in bulk and then refinance them into the “Hope for Homeowners” or another government program that insures home mortgages.

Other options include a broader push for lenders to forgive a portion of the home loan for certain borrowers, and other permanent modifications over the longer term so that loans don’t have to be modified over and over again.

Some studies have shown that nearly one-third of borrowers who’ve had their mortgages modified are in trouble again after three months.

Bernanke took pains to tie skyrocketing foreclosure rates to the deterioration of the broader economy.

“The housing market remains central to the economic and financial challenges that we face. Because housing and mortgage markets are tightly interlinked with the rest of the economy, actions to strengthen financial markets and the broader economy are important ways to address housing issues. By the same token, steps that stabilize the housing market will help stabilize the economy as well,” he said.