SINGLE person households are now the most common type of home in Wales.
For the first time, the number of people living alone has overtaken the number of couples living together.
At the same time, the number of four-person and five-person family households has been falling.
Experts said that the trend was due to more young people leaving it later to marry and elderly people living on their own after their partners had died.
Charities have warned that the rise may lead to increasing pressure on housing and more people becoming isolated.
Cultural historian Peter Stead said the growth of the single person household, a group that had increased 48% over the past 20 years, was an incredible change in Welsh society.
He said: “It’s astonishing in a way. I grew up in the Wales of the ’40s and ’50s, where the only people who lived on their own were widows and elderly people.
“Everything depended on the family – families ate together, families walked to church together, families walking to the cinema.
“It’s an incredible change in terms of society.
“There’s so much entertainment available [today], people spend hours watching TV, hours on the internet, hours on the mobile phone, you can go out on your own. There are options for people who are more at home in that world, than they are having contact with other people.
“It’s perfectly possible to chose to live on your own.”
Wales’ ageing population may be partly behind the growing number of single households, with Age Cymru figures showing 22% of men and 44% of women aged over 65 living alone.
However, Graeme Francis, head of policy and public affairs at Age Cymru, warned isolation and loneliness can be a daily reality for many older people in Wales.
He said: “According to recent research by Age Cymru, 41% of over-75s in Wales reported spending most or all of a typical day alone, while 38% of over-50s in Wales spend at least half a day alone.
“Evidence shows that older people who are cut off or isolated are more likely to need services such as home help or meals on wheels.
“We also know that some older people are deprived of opportunities for socialising and mixing with others because of poor health or a lack of transport facilities where they live.
“This is why it is vital that local authorities are supporting communities to provide opportunities for older people to take part in educational, social and health-related activities, as well as volunteering opportunities in their local area.
“Befriending schemes that offer regular social visits or telephone calls, run by local voluntary organisations, are also highly valued by many older people who live alone.
“Nowadays, it is more important than ever to find creative ways to provide these services for older people, such as allowing older people to use council facilities to hold meetings and run activities.”
With more people living alone, and in smaller households generally, the average household size has fallen from 2.52 in 1991 to 2.24 in 2010, there is likely to be increasing demand for smaller properties.
Overall, the number of households in Wales grew by 10,600 between 2009 and 2010, with the Welsh Government, which compiles the statistics, putting the majority of the rise down to an increase of 7,400 in the number of one-person households.
Michelle Wales, Shelter Cymru’s head of external affairs, said: “It is clear that the noted growth in the number of single person households will increase the need for housing.
“[Wednesday’s Welsh Government] budget announced reductions in capital spending, particularly on increasing the supply and choice of housing – this is due to be cut by 12.5% in 2012-13 and again in 2013-14, meaning that the capital spend on housing supply by 2013-14 will be 50% lower than it was in 2010-11.”
Estate agents and house builders said they had been seeing an increase in demand for smaller properties from single people.
Cardiff estate agent Thomas George said: “There are as many single people as there are couples [looking for rented property]. They’re renting small units. Demand for little one-bed apartments is rising, they’re flying out of the office.
“There isn’t enough supply, mainly because the buy to let market is very quiet.
“We’re finding in the right area, city centre or nice suburbs, even with properties that aren’t available till the 1st of December, people are reserving them now.”
He said he is seeing people living alone for longer, either because they have got used to their independence or because people are less social than they were in the past.
Barratt Homes said the company’s one-bed properties in Swansea had been a huge success, although larger properties have been more popular in other parts of Wales.
The fastest growing household type in Wales is five or more adults living together, increased 3.2% between 2009 and 2010.
Couples appear to be having fewer children, with the number of families with more than one child falling over the past 20 years, while the number of one child families has increased.
Single parent families have also risen.
However, more single people may find themselves sharing when changes to housing benefit are implemented in January, which will see under 35s only paid the rate for a shared house, rather than for a one bed property, increasing from the current age limit of 25.
Ms Wales said: “Single person households are very vulnerable to the welfare reform changes making renting for this group an even more difficult option.
“Local authorities and social housing providers are already struggling to meet the demand for homes with an estimated 70,000 households on their waiting lists.
“We argue that investments in homes must have a higher priority in Wales.”