The Government has been urged to buy some of the thousands of homes left unoccupied because of the recession.
Simon Communities of Ireland says the homes should be used to house the many families to whom the Government has promised accommodation.
The charity says the Government has fallen short of its target for social and affordable housing, and needs at least to replicate last year's funding increase to the sector.
Simon, which works to end homelessness, says that in Dublin alone there are 10,000 unsold private units, almost half of which have two bedrooms.
It wants the State to buy some of them now, a move which it says would be welcomed by the construction industry and the wider economy.
Simon says the initiative would help get the Government back on track towards meeting its commitments in Towards 2016 and the National Development Plan to provide 44,000 new social and affordable housing units over three years.
Simon adds that in 2007 - the first year of its roll-out - the programme fell behind target by 17%, but says this marked an increase of a quarter over 2006.
To sustain this improved level of growth it wants at least €1.93bn earmarked in the housing budget for next year.
