New figures show the number of people on social housing lists around the country is nearly 40,000 above the figure which had been given by the Government.
The numbers were released by Fianna Fáil and obtained under the Freedom of Information Act.
They show that the number of people on social housing lists are roughly 130,000.
Dr Lorcan Sirr is a lecturer in housing at Dublin Institute of Technology.
He says he believes the figure of 130,000 is "in any way accurate", and that it may be less.
"What you have in the social housing figures - even the existing one of 89,000 - are duplicates", he told Newstalk Breakfast.
"For some rental supplements, you have to register on the waiting lists whether you require accommodation or not; so there are duplications on the housing waiting lists".
He also says we should also open tenders to build the houses we need.
