Irish people borrowed €5.5 billion of mortgage top-up loans during the peak of the property boom.

However, new research by the Central Bank and the Central Statistics Office also shows that by last year the value of such loans had fallen by 97%.

Borrowing against the value of a property accounted for one-third of all loans issued during the housing boom.

From 2005 to 2006, there was an increasing trend for very large equity release loans of €150,000 or more - most of which appear to have been invested in other properties such as holiday homes and buy-to-let properties.

Outside of the very large loans, the average mortgage top-up loan ranged from €50,000 - €60,000 throughout the last decade.

An estimated two-thirds of these were re-invested in the property for repairs, maintenance and renovations.

The research also found that this borrowing was more common where the head of the household worked in financial services, the public sector or in construction.

However, the value of this type of borrowing has dwindled dramatically, falling by 97% to €195m of top-up loans in 2011.