New research by the Chartered Institute of Housing (CIH) estimates that 30,640 homes in Wales, including many in the private rented sector, will be put out of reach of people on housing benefit as a result of changes brought in by the UK Government in 2012.

From this month, the government has capped housing benefit payments from £250 a week for one-bedroom homes to £400 for a four-bed.

However in Wales the CIH says the biggest impact arises from other changes which link local housing allowance, the benefit paid to tenants of private landlords, to the bottom third of rents in any area. The result is that in many places there will not be enough affordable homes to rent for those claiming.

Wales is particularly badly affected with demand outstripping supply in 20 out of 22 council areas with some local authorities facing situations where three people are chasing every affordable private home for let.

Vikki Hiscocks Policy and Public Affairs Manager at CIH Cymru said: “These changes have a worse impact in Wales compared to other parts of the UK in terms of the imbalance between supply and demand they create.

“The human consequences of the changes will be immense with thousands of people unable to access local housing and forced to migrate raising the possibility of creating benefit ghettos.

“There is concern that many private tenants will be faced with the choice of losing their home, borrow more or cut back on what they spend on food for themselves and their families.

Crisis the charity for homeless single people, which has been campaigning against the new housing benefit acts, believes the changes are creating a stark outlook for the whole of the UK. The organisation estimates the changes will affect a million households up and down the country.

Crisis claims research by the University of York, which was commissioned by the charity, demonstrates that housing benefit acts as the main buffer between low-income and jobless households and homelessness.

A Crisis statement said: “That buffer is now being dismantled and if the Lords don't stand up and challenge further cuts and caps before them in the welfare reform bill the gap between rents payable and benefits received will, we fear, become unbridgeable for countless families and individuals across the UK.

“Letting thousands slip into homelessness is not without a price. Costs will be borne by the NHS, schools, local authorities and central government, and it will become harder for people to stay in or find employment.

Crisis chief executive Leslie Morphy added: “The human cost is even steeper. What sort of government takes the decision to make people choose between food, warmth or shelter?

“Attacking housing benefit amounts to attacking those in our country least able to defend themselves. Much misunderstood, in reality it is all that stands between poor, often working, households and very bad housing or the horrors of homelessness.

“I urge the government to rethink before we do irreversible damage to the poorest in our country and by extension to us all. Carrying on blindly down the current path is not only wrong but counterproductive on its own terms.

“It is also a common misconception that these reforms will only impact on people who are unemployed. There are an equal number of people affected who are currently in work.”