A survey of local residential property sales today claimed that Northern Irish house prices had risen by more than 22 per cent on average from the previous year.

A survey of local residential property sales today claimed that Northern Irish house prices had risen by more than 22 per cent on average from the previous year.

The latest University of Ulster Quarterly House Price Index also shows that properties in some areas increased in value by 36 per cent.

Apartments are reported to be the biggest growth area, with average prices rising by almost 33 per cent in the year to £129,456. The terraced and town house markets were also strong, experiencing 28 per cent growth.

"The reality is that gains like this are only on paper – but consistent house-price inflation promotes a feel-good factor among consumers," said Professor Stanley McGreal, one of the report's authors.

Economist Alan Bridle, Bank of Ireland's head of research in Northern Ireland, said that these increased rates were unsustainable but he did not see any sudden crash in the housing market while borrowing remained cheap and the investment market was so strong.

But the Housing Executive's head of research, Joe Frey, said that such substantial growth was "unsustainable even in the medium-term" and that market changes would occur "sooner rather than later".

A recent survey showed similar growth in certain parts of Scotland during the course of 2005.

In some areas of Lanarkshire and Dunbartonshire, property prices rose by 35 per cent, revealed Bank of Scotland, which also claimed that house prices were rising three times faster in Scotland than in the UK.