A "perfect storm" of rent rises, insecure tenancies and the effects of recession means families who never dreamed of being homeless could end up on the streets, a housing organisation has warned.
The National Housing Federation (NHF) believes these families are the "new face of England's homeless" and says the only solution is to build more affordable homes for sale or rent.
A new report published by the NHF shows 1,660 families with children and pregnant women were living in bed and breakfast accommodation between January and March 2012, which is a 60% increase on the same period in the previous year.
The Homeless Bound report - which focused on council areas in London, the South East and East of England - also says 36% of families with children living in B&Bs had been there for six weeks or more.
The NHF said this figure has risen by more than 200% in the last two years. It also said information is not collected on how long families stayed beyond six weeks so the full extent of the problem was not known.
The federation said its report is published against a background of a rise in the number of rough sleepers in England. It said there had been a reduction in rough sleeping of two-thirds between 1998 and 2002 and then levels remained static until 2009. But the NHF said there had been a 23% increase from 2010 onwards.
It said 43% of councils in London, the South East and East of England reported that rough sleeping had increased over the last year.
David Orr, chief executive of the NHF, which represents England's housing associations, said: "With increasing rents, insecure short-term rental tenancies and a recession which is leaving people really struggling, we have a perfect storm - and it means families who never dreamed of being homeless could end up on the streets. They are the new face of England's homeless.
"Local authorities' new powers to move homeless families waiting for social housing straight into the private-rented sector may cut the numbers living in temporary accommodation. But renting privately is still unaffordable - as the 86% rise in working families claiming housing benefit shows.
"And with private landlords increasingly unwilling to house homeless families, we could see a revolving-door effect where people who can't afford their rent simply become homeless again. The only solution is to build more affordable homes for sale and for rent. Only then will we truly be able to protect people from the traumatic experience of being made homeless."