In June, Alex Baulf, 26, who works at a tax consultancy in the City, left the comfortable bachelor pad that he shared with a friend in Fulham, southwest London, and moved back in with his parents in Tunbridge Wells, Kent. It was one move he never imagined he would make.

Baulf, who had been living in London for nearly three years, decided he simply couldn’t afford to live independently any more. “I wasn’t able to save at all, with rent and the additional costs of being in town,” he says. “I couldn’t envisage saving for a deposit.” Even allowing for the cost of commuting (£55 a week on train tickets, plus the odd taxi), Baulf claims he is able to save £275 a month by not paying rent — and because his socialising has been curbed somewhat now he’s back at home helping with the washing-up, rather than going out.

What do his parents think of the arrangement? “It’s lovely having him at home, but he still thinks he’s a teenager,” says Alex’s mother, Jennie, who has recently retired. “The bedroom’s left in a mess and he’s meant to do the washing-up every night, but it doesn’t always get done.”

Such familial complaints over tidiness, personal hygiene, cooking habits and a busy social life are making a post-adolescent comeback for a generation of twenty- and thirtysomethings who, like Baulf, are returning to the parental nest.

While it may be normal to return home after university, this group have lived away for a while, but are now coming back again — often with boyfriends and girlfriends in tow, or even husbands and wives.

New cases of boomerang kids are springing up every day. One couple I know, who married several years ago and bought a flat in southwest London, upped sticks and went travelling for six months, letting out their flat, which they planned to sell when they returned. They hadn’t anticipated the credit crunch. He is still looking for a job, so they have moved into her parents’ house and are renting out their flat to save money. Another friend worked at Lehman Brothers; now he and his wife are thinking of giving up the tenancy on their expensive flat in Notting Hill and moving in with her parents.

In these credit-squeezed times, increasing numbers of young people who have previously enjoyed independent lives are moving back into the family home — because they can’t afford to pay rent and save for a mortgage at the same time, because they have lost jobs or simply because the cost of living has become too high.

The trend has been on the increase for a while — figures from the Office for National Statistics showed that, in 2006, 58% of men and 39% of women aged 20-24 in England lived with their parents (an increase of 8% since 1991); according to more recent research from the Prudential, nearly one in five adults now lives with grown-up children, and a third of parents expect their children will live with them past the age of 21. So extreme is the situation becoming, in some cases, up to four generations are living in the same property.

"It's become a huge issue, and is particularly pronounced in London and the southeast, because of the cost of accommodation," says Liam Bailey, head of residential research at Knight Frank, who has worked with local authorities on this subject. “After the war, the government policy was to reduce overcrowding, and they almost did it — but, over the past decade, it has risen again quite considerably.”

All sorts of factors are to blame. The ever-increasing amount of student debt is one — according to the National Union of Students, the cost of being a student stands at £13,135 a year, or £15,214 in London. Debt campaigners predict that by 2010, graduates will have average debts of more than £30,000.

Then there is the difficulty of getting a foot on the housing ladder. The most recent report from the Halifax shows the number of first-time buyers at its lowest since 1980. Meanwhile, only 15,600 mortgages were approved for those buying their first home in August, 55% less than in the same month last year, according to figures from the Council of Mortgage Lenders (CML). Factor in the current economic and employment uncertainty, and this boom-erang generation look as if it may be staying a while.

“These are people who have lost their jobs or had short-term contracts,” says Julia Margo, head of the capabilities programme at the think-tank Demos. They are frequently young men, she adds. “Often they are not in stable relationships and have nowhere to go, so they go home.”

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