Tenants in London are being forced into sharing rooms, often with complete strangers, as rent in the capital becomes increasingly unaffordable.

Flat and house share site SpareRoom.co.uk has seen a 71% rise in searches for bedroom shares over two years.

Its director, Matt Hutchinson, said: “We know many couples are sharing rooms in house and flat shares with other people to save money, but there’s also a rising number of single people sharing rooms now too.

“Few people would choose to share a room, but the harsh reality is that London’s housing crisis means rents are becoming increasingly unaffordable.”

One twin room in west London is currently being offered to tenants at £259 per week. Bunk beds are also regularly listed as “twin” rooms.

In 2014, 93,505 adverts were placed on Kangaroom, a site that helps people find a spare room in a house share, by people looking to share either twin or even triple bedrooms – an increase of 48% from 2013.

Jinder Sidhu, founder of Kangaroom, said bedroom shares now accounted for just over 10% of the market.

“While rent prices in general rose by 7.5% in 2014, room-share prices have decreased by 12% due to increased supply and denser living conditions.”

Tove Eriksson and Francesca Whitlock, both 25, have been friends since they met during freshers’ week at Leeds University. After graduating, Eriksson went home to Sweden, while Whitlock, from London, went to teach English in Chile, but they stayed in touch.

Then, last autumn, like so many of their friends, the two women, looking to live in a larger house share with other friends, were shocked by the high rent prices in the capital. They soon realised their only affordable option was to share a bedroom.

They admit it is not an ideal situation and that their friends and family reacted with shock when they moved in together.

Eriksson is a project coordinator for Seven, a women’s rights theatre project. The role, although paid, is only part-time, so she works as an office temp for the rest of the week.

She had hoped to begin earning enough to afford a room on her own, but now thinks that will be a long way off as she still has only enough money to cover half the room rent. “I’m dependent on sharing. It’s either sharing a room or not living [in London],” said Eriksson.

Whitlock, who is just about to start work as a campaigns intern at the Climate Coalition, believes living in London is the only way for her to build a career doing something she is passionate about. She said: “It’s tricky – you feel you have to be here – but you have to pay absurd rents.”

Whitlock and Eriksson both said they realised how lucky they were to be sharing with a friend.

Whitlock said: “To share with someone you don’t know – I don’t want to use desperate because that’s not a nice word to use but, what a horrible situation to be in if there is no other way you can live.”

For housing and rent campaigners, this trend is worrying but inevitable. Campbell Robb, Shelter’s chief executive, said: “With our housing market out of control and rents sky-high, it’s no surprise that people across the capital are having to resort to these sort of measures just to keep a roof over their heads.

“But it’s simply not right that people are being forced to share their personal space with someone they barely know just so that they can make ends meet each month, let alone save money to build a stable future.”

“The only way to end this madness is for politicians to roll up their sleeves and commit to building the genuinely affordable homes we so desperately need.”

At the March for Homes on 31 January tenants, trade unionists and campaigners plan to march on City Hall, London, calling on Boris Johnson and councils to address the lack of affordable homes in the capital.