PIBA, the country's largest group of financial brokers, has reiterated its call for the Central Bank to soften its mortgage lending rules, introduced in 2015. Brokers want the regulator to reduce the 20 per cent deposit requirement to 10 per cent, with the maximum loan amount being increased from 3.5 to 4.5 times income.

"The problem in the mortgage market is the severity of the lending rules rather than the exemptions," Rachel Doyle, chief operations officer said, noting that Irish rules are "extremely restrictive by international standards".

"In the UK, for example, the Bank of England and Financial Conduct Authority in 2014, in responding to exactly the same concerns as the Irish regulator, introduced a 4.5 times loan-to-income threshold and now places greater emphasis on likely income into the future and far closer scrutiny than previously into outgoings. The focus on outgoings as well as income is a very real and practical response to the issue and it encourages mortgage applicants into better financial planning. It is a discipline Irish lenders, if albeit in self-preservation mode, had already introduced since the financial collapse, obviating the need for more stringent rules now, however necessary they may become at a later point," she said.

While exemptions to the rules are allowed, Ms Doyle noted that as there is no criteria on these set by the Central Bank, apart from a percentage of overall lending, lending institutions set their own particular criteria “which vary hugely and are reviewed on an ongoing basis”.

“Exemptions are crude and quite ridiculously sometimes dependent upon the time of year and whether or not the banks are getting close to their overall lending limits. This situation which is a fault of the overall system forces those who are just outside the strict rules for qualifying to wait until the beginning of the next calendar year where there is a better chance of getting an exemption. It creates mortgage by calendar,” she said.