Increasingly, London families plan to incorporate a self-contained apartment within their homes to provide a cheap, safe but private haven, either for elderly relatives or grown-up children.
Experts say that sales of homes that already have a granny flat or annexe are also booming.
Two in five London homes are already multigenerational, with adults living alongside their elderly parents and/or grown-up children, according to a new report by insurance giant, Aviva.
Almost one in 10 homes in the capital has some form of granny flat or annexe, while another 12 per cent of owners say they now have plans to develop one, the report reveals.
Of course, granny flats were traditionally created with elderly relatives in mind, but “boomerang” children are now equally likely to live in one thanks to high property prices.
“The events of this year have focused many people’s minds on the home,” says Gareth Hemming of Aviva.
“We’ve already seen that 85 per cent of householders made some form of home improvement during lockdown, but this study suggests some have more radical developments in mind.
“Lockdown changed the make-up of some households, as young people returned home from university and older people joined support bubbles, so it’s possible that this has helped to crystallise people’s ideas for family accommodation.”
Marc Schneiderman, director of Arlington Residential estate agents in St John’s Wood, says that right from the start, lockdown brought a “colossal increase” in the number of buyers looking for a home incorporating a self-contained unit.
“The demand for this comes from people seeing working from home as the new future, and from buyers keen to have children or other relatives still under one roof but in separate spaces,” he says.
“It can take the form of annexes, self-contained lower-floor flats, adjoining coach houses, or even buying the flat upstairs or below and knocking through whilst retaining separate entrances.
“The demand is such that the right buyer requiring a separate space within, or alongside a house, is likely to pay a premium of around five to 10 per cent compared to the same amount of space that does not have a self-contained element.”
Grand granny flat: Clarence House was used as the Queen Mother’s residence after her husband’s death and daughter’s coronation (AFP via Getty Images)
Granny flats are the modern incarnation of the aristocratic notion of the dower house, a usually rather grand home built within the grounds of country estates to house the widow of the previous holder of the estate. This allowed the main house to be vacated for an heir.
Clarence House, for example, was used as the official residence of the Queen Mother from 1953, following the death of her husband King George VI, until her death in 2002.
The Oscar-winning actress-turned-politician Glenda Jackson, 84, currently lives in a basement granny flat in Blackheath with her son Dan Hodges and his family.
Building a granny flat: what you should know
Whether you need planning permission for your granny flat depends if it is within your home or in the garden, and if the property is listed or in a conservation area. In any event, it is always best to consult your local council before doing any work.
According to the HomeOwners Alliance, creating a detached granny flat in the garden will definitely require planning permission, and you may also need to apply if you intend to convert a detached garage into a flat.
If you plan to reconfigure your existing house space, you are less likely to need planning permission, but do always check. And if you are going to build an extension to make space for the granny flat, it will be subject to normal planning rules.
If you build a detached granny annexe — or buy a property which already has one — you won’t have to pay stamp duty on it. This surcharge was scrapped in 2014, so long as the annexe is in use by a family member.