There will be 70,864 households where the head of the household is over 65 by 2041, calculations by the Office for National Statistics show – a rise of 46 per cent.
And households with people over 85 will more than double, rising by 134 per cent to 14,777.
Age UK, a charity working with older people, says a “revolution” is needed in social care to support the ageing population in their own homes.
Older people account for most of the growth in the number of households in the next two decades.
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Joanna Harkrader, from the Centre for Ageing and Demography at the ONS, said: “We project the majority of household growth over the next 25 years will be because of the rise in the number of households being headed by someone aged 65 years and over.
“This shows the impact an ageing population is having on household growth.”
The ONS defines a household as a single person living alone, or a group of people who live at the same address and share rooms and a kitchen. A household may be a family, more than one family, or a group of unrelated people.
Dr Elizabeth Webb, of Age UK, said it was great news that people were living longer. She said that while many would remain independent there would be a growing need for health and social care that could not be fulfilled already.
“The over 85 group is the fastest growing and the most likely to have the greatest needs for social and health care, which has an impact on the health service.” Dr Webb said.
“It’s about having a person there to help get them out of bed, help them wash and dress and to put a meal on the table. This needs people, not a technological solution.
“The social care workforce is understaffed and there’s not enough cash to provide the support that’s needed.”
Dr Webb added: “Older people today are more likely than future generations to have children to help care for them. In future we’ll see more people living alone and more without someone to care for them.”
The projections show that the number of younger households in Northumberland will fall by 2041. Under 25 households will go down by 21 per cent and the 25-34 age bracket by eight per cent.
The ONS believes that by 2041 there will be an extra 4 million households in England, but this is fewer than previously forecast. It says that the slower growth is due to assumptions about births, life expectancy, migration and new forecasts on the numbers of people who will continue to live with parents or cohabitate.
The projections show that in Northumberland the number of households will climb to 150,166 by 2041, while the population will shrink by 5,358 to 306,184.