The great American retirement dream of playing golf and doing gentle water aerobics in the sun, surrounded by like-minded seniors, is the latest victim of the credit crunch.

Retirement communities across the United States face an influx of younger families after being forced to reduce or scrap age restrictions for residents in order to sell houses. Increasing numbers of properties in so-called age-restricted developments are lying empty as the recession continues to bite the housing market and baby-boomers defer retirement.

In an attempt to stimulate sales, developers and community associations are reducing minimum age requirements, usually set at 55 or more, for new buyers at many retirement communities. At some new developments, age restrictions are being eliminated.

Ralph Zucker, president of Somerset Development, a property developer, had already tried cutting 25 per cent from the price of a home at his new Pine River Village development, in Lakewood, New Jersey, to try to offload 143 unsold properties.

Now Mr Zucker is going through the process of removing the 55-plus age restriction on the unsold portion of the development. “People are thinking much longer about how they want to spend their money and what they want to do with their lives,” he said. “These people don't have to buy, they've already got somewhere to live.”

Mr Zucker has the support of the 32 households that have so far bought into the 175-property Pine River Village. Otherwise, they face living next to unfinished properties and the prospect of increased costs to maintain the development's facilities, including a fitness centre and indoor pool.

However, similar moves at some finished developments face opposition from residents who fear that younger neighbours will bring with them increased crime and nuisance.

At the same time, communities face an uphill battle convincing local authorities, which gave permission for the developments because age-restricted communities do not need expensive amenities such as schools, to approve the new rules.

Retirement communities first gained popularity in the 1960s. Retired people admired the strict rules on home maintenance, the tight security and the facilities geared to pensioners' needs. In most cases, the communities must ensure that at least 80 per cent of residents are aged 55 or older, or that at least one member of each household is 55-plus, in order to meet federal rules that allow them to exclude children.

However, the property market slowdown - sales of existing properties fell 8.6percent last month, according to the National Association of Realtors - means that retirement community residents are not being replaced when their properties become empty.

Figures from the National Association of Home Builders show that the number of households in 55-plus “active adult settings” fell from 1.8 million in 2001 to 1.1 million last year.

The problem has been worsened by a gradual change in the way that Americans view retirement communities. A recent survey by AARP, a group for older people, found that almost nine in ten respondents said that they did not want to move home when they retired, instead opting to “age in place”.

Mr Zucker said: “For a long time, the active adult market was fuelled by people who bought because they were sure that the value of the property would go up. But there's been a general shift to people wanting to stay with family, closer to their children. The concept of moving to Florida to retire has lost its charm.”

Without a gradual stream of the newly retired to replace increasingly inactive, ageing residents, retirement communities can struggle to cover the cost of facilities such as golf courses.

Sun City Grand, in Surprise, Arizona, decided last year to allow up to 15 per cent of its 9,802 homes to be owned by people aged 45 to 55. Since the rule change, Sun City Grand has sold 200 homes, lifting its younger population to 2 per cent. The community still forbids permanent residents aged under 19.

Meda Cates, of the Sun City Grand Community Association, said: “You move to a senior community because you want to live with people the same age. We love our grandchildren, but maybe we don't want to live right next door.” However, she added that there had been “absolutely no downsides” to dropping the age restriction. “The new residents fit in perfectly,” she said.

Sun City altered its rules after the decline of two nearby retirement villages. “We saw our neighbouring seniors communities growing older,” Ms Cates said. “This is a way of stalling the ageing process. It wasn't strictly for financial reasons; it was also for aesthetic reasons. We're an active community and we want to attract 55 to 60-year-olds, but they won't come here if they feel that it's an older, inactive community.”

There are no official figures on the number of retirement villages altering age rules, but they appear to have been eased or ended for at least nine new developments in New Jersey. However, residents at The Esplanade in Hudson, Massachusetts, are fighting such an alteration by the developers.

To ease relations with existing residents, Mr Zucker promised to keep younger buyers on one side of Pine River Village, to create separate entrances and even to build a dividing fence if necessary.

He is confident that he will win local authority approval for the change because local schools are under-populated rather than over-populated.

“It's very difficult to get approval for a change once a community is well under way,” he said.

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