About 100 homes were repossessed by banks after the borrower was denied the right to tracker mortgage rates, the Central Bank has said.
The number was revealed as the regulator was forced to concede that the scale of the scandal was almost twice as big as a report had claimed a day earlier.
The Central Bank's review of the controversy where banks either refused customers access to low tracker rates or did not make it an option initially put the figure at 8,200.
But amid damning criticism at the Oireachtas Finance Committee, where chairman John McGuinness accused Central Bank governor Philip Lane of being afraid of the banks, the head of the regulator said the real number was about 15,000.
Mr Lane said: "This is a tremendous problem and we are expecting significant redress and compensation which of course has to be a special case for people who have lost their homes."
The committee hearing was suspended after the Central Bank chief faced a withering attack on its assessment of the scale of the tracker scandal and was ordered to get more complete numbers.
The refusal of banks to allow customers to move on to tracker rates first emerged as far back as 2010 - the year taxpayers were lumbered with a multibillion-euro bailout.
In the six years since banks have repossessed more than 7,500 homes and apartments.
Mr McGuinness told Mr Lane that the information on tracker refusals, or lack of it, was striking.
"Are you bullied by the banks? Is the Central Bank ready for the banks? That really is the question that emerges in my mind," he told the regulator.
"I would conclude from the information that you are giving and how you are approaching this is that you are afraid of the banks, that you are afraid to take them on."
The Central Bank governor hit back: "There is zero basis for that."
Mr McGuinness accused Mr Lane of being unwilling to set out the exact totals involved in the tracker scandal or to play "hardball" with the banks.
"It would seem to me that you either feel bullied by them or that you are fearful of them, but you are not engaging as I would expect you to engage," he said.
The clash took place in the wake of a report from the Central Bank which revealed that at least 8,200 home owners were blocked from moving to tracker mortgages, the lowest interest rate in the market.
Mr Lane said banks were now under an "extremely intrusive regime" and added: "We have no reason as supervisors or regulators to go lightly on the banks."
The Central Bank said 2,100 Bank of Ireland mortgages were restored to tracker rates when the issue was identified in that bank in 2010 and 2011.
It is understood refunds were made for the overcharging but no compensation was given.
There were also about 1,400 cases of customers being denied tracker rates involving Springboard Mortgages, which was a subsidiary of Permanent TSB.
It is understood these numbers are on top of the 8,200 other cases identified in the Central Bank trawl of trackers, which looked into 15 lenders from late 2015.