CSO data released this week shows home prices in Dublin are now between nine and 14 times the average salary.
Houses and apartments in the capital have risen over 92% since their low point in the property crash.
Central Bank rules mean people can't borrow more than three and a half times their salary.
John Mark McCafferty, chair of housing charity Threshold, says high costs mean people are stuck in the rental market:
"People are effectively locked out of home ownership, especially younger people and people on middle incomes," he said.
"Some will now spend the rest of their lives in the private rental sector and that puts huge pressure on that sector especially given the affordability issues related to renting and the lack of security of tenure that many people face."