Rising interest rates are feeding through to house prices, according to the latest monthly data from the Economic and Social Research Institute (ESRI) and Permanent TSB.

For the first time this year, growth rates across all market sectors have stabilised or fallen on the previous month's figures.

The data shows that prices nationally jumped 1 per cent in August, the third month in succession that the rate of growth has slowed. The average price of a home in the Republic is now €306,173. That is €28,000 above the level at the end of last year.

Prices are still rising more rapidly in Dublin than elsewhere with the average property in the capital costing €412,877 last month, 17.2 per cent more than in August 2005. For homes outside Dublin, the average price last month was €264,622.

Permanent TSB said there was a "clear trend of slowing price growth in the Irish housing market, following the recent series of European Central Bank rate increase".

However, it notes that the 10.2 per cent rate of growth in the first eight months of the year is well ahead of the 4.4 per cent recorded for the same period last year, and even the 9.3 per cent rise in prices for the whole of 2005.

Over the 12 months to the end of August, prices across the State rose by an average of 15.4 per cent. That is the same as the July figure and the first time in a year that the annualised growth rate has not risen.

The figures were published a day after other survey data from DKM economic consultants showed that higher prices and rising interest rates will see couples in Dublin spending 40 per cent of their net income on mortgage repayments by the end of this year - up from 29 per cent in July last year.

Nationally, mortgage costs will account for 31 per cent of disposable income by year-end compared to 23 per cent in July last year, according to the EBS/DKM affordability index.

Auction room results also indicate the market is softening after a bumper first half of the year. Around 70 per cent of properties to come under the hammer this week were reported to have failed to find a buyer.

"All this points to the heat being taken out of the market and house price growth reaching the top of the curve," said Niall O'Grady, head of marketing at Permanent TSB.

Interest rates are expected to rise again next month, by a further quarter percentage point, and that trend is expected to continue through 2007, according to market commentators.