The Government has said its housing strategy will supply up to 110,000 homes over the next six years, including 35,000 social housing units at a cost of €3.8bn.
Minister for the Environment Alan Kelly announced that the State will also support up to 75,000 households through what he called "an enhanced private rental sector".
Announcing the strategy, Mr Kelly also promised to reform social housing supports to create "a more flexible and responsive system".
The strategy comes in two phases, with the first to be delivered by the end of 2017, setting a target of 18,000 additional units and 32,000 other homes where the State pays most of the tenant’s rent.
The second phase, to be delivered by the end of 2020, sets a target of 17,000 additional units and 43,000 more homes where most of the rent will be paid under the State’s Housing Assistance Payment, which is replacing Rent Supplement, and the Rental Assistance Scheme.
The Government said the strategy will build on spending commitments already delivered in October’s Budget, where it was announced that €2.2bn would be provided to deliver 10,000 social housing units by 2018.
There are currently 90,000 households on the list.
The housing situation is particularly acute in Dublin, where there are 19,000 families on the waiting list.
Many cannot afford the private rents being charged in the capital.
Of the 19,000 families on the list, more than 7,500 have been waiting for five years or more.
The homeless figures in Dublin are increasing, with 1,526 adults in emergency accommodation.
Mr Kelly said it was probably the most important day in the lifetime of the Government where social policy is concerned.
He was speaking at the official opening of 20 newly-finished apartments in Inchicore to house families who were on Dublin City Council's housing list, some for as long as seven years.
The development, which was carried out by the National Association of Building Co-operatives, is part of a mixed-usage complex with social housing comprising one-sixth of the total units.
Mr Kelly said that under the new social housing strategy building co-operatives and voluntary housing associations will be given access to funding to develop similar schemes to the one in Inchicore.
The Government's housing policy was discussed at a meeting of the Fine Gael parliamentary meeting tonight.
Taoiseach Enda Kenny also told the meeting that there will not be a general election next year.
Fianna Fáil's environment spokesman Barry Cowen said that when former minister Jan O'Sullivan assumed office she said that homelessness would be eradicated by 2016.
Speaking on RTÉ's News at One, Mr Cowen said the plan announced today only appears to address the problem from 2016 onwards.
He rejected the view that the housing crisis is the result of the previous government's over-reliance on privatisation to meet social housing needs.
He said this plan appears positive and dramatic, but he has reservations about it bearing closer scrutiny.
Mr Cowen also questioned whether the plan is top-heavy on short-term solutions, and pointed out that the proposals in relation to housing assistance payments were not a long-term solution.
In a statement, Richard Boyd Barrett for the People Before Profit Alliance said the plans will not even begin to address the current housing and homelessness emergency.
'Families cannot wait'
Housing charity Threshold welcomed the announcement, but said immediate measures must be taken to help families facing homelessness.
It expressed concern over the timeline for the implementation of the housing strategy.
Threshold Chief Executive Bob Jordan said funding for social housing was "decimated" during the recession and it will take a long-term and strategic approach to undo that damage.
He said families facing homelessness cannot wait for two or more years while the Government gets this strategy under way.
Focus Ireland warned that the challenge now is in delivering the homes required to tackle the growing housing and homeless crisis.
It also said the Government must learn from past mistakes and ensure that the communities built are sustainable ones with access to employment opportunities.
The Peter McVerry Trust also gave a broad welcome to the strategy, saying it placed the State back at the heart of social housing provision.
It said priority in the initial stages should be given to homeless households and by ring-fencing even a small number of units over the next three years it would help significantly reduce the number of homeless people.
The Society of Chartered Surveyors Ireland (SCSI) said the plan to build or refurbish 35,000 social housing units by 2020 would go a long way to address the problems facing the estimated 90,000 people in need of support.
The SCSI stressed, however, that the measures had to be implemented as a matter of urgency.
However, Simon Communities said the strategy does not address the current homeless crisis, which it said needs urgent intervention.
Spokesperson Niamh Randall said the charity is deeply concerned the strategy does not meet the needs of the people it works with, such as people trapped in emergency accommodation and those sleeping on the streets.