The cost of renting a family home in Hertfordshire has rocketed by 22 per cent over the last four years, new figures have revealed.

According to the Valuation Office Agency, the median monthly rent for a three-bed family home in Hertfordshire was just £1,100 in the year to March 2014. Four years on and that figure has spiralled to £1,340.

Renting in St Albans is even more expensive: the median monthly rental price has risen by 19.7 per cent over the last four years, and a three bed family home now costs £1,500 (up 14.2 per cent).

More than one in five UK households currently rent privately – the highest number ever. By 2021 this figure is expected to have increased to one in four.

Soaring house prices have put home ownership out of reach for many adults, with those in their 20s and 30s nicknamed Generation Rent as a result.

Dan Wilson Craw, director of pressure group Generation Rent, said: “Renters are in a bind. If they choose to live where there’s a strong jobs market they might see their pay packet gobbled up by high rents.

“If they live somewhere cheaper, either there’s a risk that it’s harder to find a stable job or they pay for it in higher commuting costs.

“The government must make renting a more secure arrangement, with restrictions on rent rises and unfair evictions, but also look at how to introduce a living rent that ordinary workers can afford.”

Lawrence Bowles, research analyst at estate agents, Savills, said: “The outlook is strong for investors. However this is less positive for tenants.”