Socialist Party TD Ruth Coppinger has focused on the housing crisis in her opening statement to the Dáil.
Ms Coppinger won her seat in the Dublin West by-election at the weekend and was introduced to the Dáil on Tuesday.
She called on the Government to use a €5bn fund for strategic projects to tackle the housing shortage.
"€1bn could build 8-10,000 social homes, so more than 50,000 houses could be built from the Strategic Investment Fund," she said.
Ms Coppinger said this could resolve the crisis "within three years if the political will was there".
She said: "This is far from fanciful. In 1975, over 8,000 council houses were built. During the more recent boom, up to 80,000 homes a year were built by the private sector."
The Government announced last week that 900 dwellings would be built for the homeless each year for the next three years.
