Advancing mortgages of 95 per cent of property values could have serious implications for debtors if there is a dip in the market, the Institute of Professional Auctioneers and Valuers (IAPV) has warned.

Its latest survey shows that second-hand house prices rose on average by 8 per cent for the first half of 1997. In Dublin, second hand house prices rose by 14 per cent on average, according to the national property survey.

Figures from the Department of the Environment in June showed that second-hand house prices rose by 18 per cent on average, and by 21 per cent in Dublin, for the year to end March 1997. But IPAV secretary Mr Liam O'Donnell said that, while members were optimistic about the housing market, they had reservations about the high rates of mortgages to property values.

"Worse still, if things go sour on the EMU front, and interest rates were to rise instead of fall, as everyone expects, then many middle income families could be in serious financial difficulty," he said. Co Tipperary was the only region to experience a decrease in houses priced between £80,000 and £100,000.