Derelict buildings: Used by hidden homeless

Crisis says that so many people are now without their own homes they could match the population of Manchester.

It wants housing experts in government to measure by the true extent of the problem.

But officials have questioned Crisis' figures, saying the charity's estimates have no resemblance to the true situation.

The charity says hidden homelessness means people who constantly live in temporary accommodation, including staying with friends or in hostels.

According to official figures, there were some 97,000 households (individuals or families) classed as homeless by local authorities in January this year.

But Crisis says there are at least 310,000 and as many as 380,000 people living in hidden homeless conditions.

The majority of these people are single and sleeping on floors at the homes of friends and family in "concealed" homelessness, it says.

According to the charity's estimates, first drawn up in 2002, a quarter of these are either living in hostels, bed and breakfasts or under threat of eviction because of debt.

Others it classes as hidden homeless include people living with family who may want a place of their own.

Estimates of costs

Taking official figures as a starting point, Crisis says as much as �1.4bn could be being lost a year through not tackling hidden homelessness.

That figure includes estimates of theoretical earnings were people working, the costs to the criminal justice system and benefits payments.

Shaks Ghosh, chief executive of Crisis, called on government to conduct a census of hidden homelessness to identify the full scale of the problem.

"Hidden homelessness is a problem that can be solved," she said.

"We need to understand the true scale of the problem so it can be tackled with the right solutions."

But a spokeswoman for the Office of the Deputy Prime Minister said Crisis' estimates on homelessness and its costs were not "an accurate reflection" of the situation.

"The Government monitors trends in homelessness on a quarterly basis, and its figures come from local authorities and voluntary agencies that record the number of rough sleepers and those presenting themselves as homeless to local councils," she said.

"There may be wider groups of people who experience homelessness at some point in their lives but who do not turn to local authorities for help - possibly because they do not think of themselves as being homeless or inadequately housed.

"Crisis may have included these groups in their figure of 380,000."

The spokeswoman added that local authorities have a duty to not only tackle homelessness, but to provide advice to anyone who seeks it.