NOT SO long ago, it was accepted that people left home at 18. Some went out to work, others went to university. Either way, when your schooldays were over it was time to stand on your own two feet.

But times have changed. Welcome to the Boomerang Generation: the twentysomethings who return to the family home after graduation and cannot — or will not — leave. In America this is a well-recognised phenomenon; books with titles such as All Grown-Up: Living With Your Adult Kids abound. In Japan it is common for single women to live at home well into their thirties; in Italy one third of all single men aged between 30 and 35 still live at home.

It looks as though we are following suit. Government figures indicate that in Britain 58 per cent of men between 20 and 24 and 42 per cent of women of the same age still live with their parents. This is an increase of 2 per cent for the boys and 5 per cent for the girls in just two years. In 1991 the figures for boys and girls were less than half of these.

The situation is becoming so commonplace that there are new words to label those living at home into their twenties: they are “kidults”, “chadults” or “kidultescents”. The engine of this trend is soaring house prices. Research by Halifax, the mortgage lender, suggests that first-time buyers cannot afford a house in 92 per cent of Britain’s towns. The average price of property in London is now an eye-watering £257,195 and, nationwide, the average house price has passed the £100,000 mark in every county. When you factor in university debts of at least £15,000, and that the average graduate’s starting salary is £22,000, buying a first home seems impossible.

Although renting is an option, many feel it is money down the drain and would rather stay at home and save for a deposit. Added to this, if the family home is in a convenient location and home life tolerable, it can seem an unnecessary extravagance to leave.

“House prices are high at the moment because there aren’t enough,” says Lord Best, director of the Joseph Rowntree Foundation, the social research charity. He blames the shortage partly on people getting married later and living separately, soaking up housing. “When there isn’t enough of something, the market will find ways of extracting the maximum price for it.” Some parents give their children a “golden handshake”. The foundation found that such parents expect to spend about £17,000 on getting their child into their first home. In the South it is £24,000.

But living with your grown-up children need not be hell, says Phillip Hodson, a specialist in family therapy. He believes that the secret of living harmoniously with grown-up children is to employ some classic conflict-resolution tactics. “When a problem arises, rather than listing someone’s faults and using that very destructive phrase ‘You are’, say instead ‘I feel’, or ‘When this happens, it upsets me’.”

If, says Hodson, you embark on a character assassination of your child, it will lead on to a tangential argument about the parent-child relationship, which is not the point. “The issues are the tidiness, the noise and the hygiene.”

It is not easy, though. Managing your children as they face the uncertainty of the real world and possibly lengthy unemployment is tricky. “It is a delicate process and you can drive your children into depression and stupid behaviour if you handle it badly,” Hodson says.

Getting your children to do the washing-up once in a while helps, but the biggest source of tension often tends to be the lack of space. “I think that it is impossible for people to live comfortably cheek by jowl, sharing all facilities and hearing everything that everybody does,” adds Hodson. “If you lived in a 30-room mansion, I doubt that there would be any problems.”

Even if your house does not come with servants’ quarters and a moat, many families find that living with grown-up children is not so bad. In fact, it is often the case that they get along better once the child has returned from university and teen tantrums are a thing of the past.

So, when your children say, “Mum, I’m coming back home; I may be there some time”, do not despair. Living with them might not be that bad, and — who knows? — when they finally leave, you might even miss them.

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