An ESRI economist is predicting young people in Ireland will be living with their parents until the age of 35 unless many more houses are built each year.
The warning comes from Professor John Fitzgerald of the ESRI, who said in Dublin, in the 36 months between January 2011 and December 2013, building commenced on only around 2,000 new homes.
Professor Fitzgerald said a number of factors are putting pressure on the housing stock.
"With rising rents and rising house prices, it's going to become more difficult," he said.
He also said the high levels of youth emigration were still not enough to make an impact.
"Basically there aren't that many people dying in Ireland vacating houses. There are an awful lot of young people … you're looking at probably needing 20 -25,000 dwellings a year to house us."