Most of the spaces were rented out by using car parking agencies that take a small cut of the earnings for their part in bringing together a homeowner with someone who needs a parking space.

The study carried out by Direct Line Insurance found that 3.5m so-called “driveway landlords” were renting out their driveways for as much as £160 per month and were boosting their incomes by around £1500 per year - even after agency fees were taken into account.

Those living in Sheffield were able to command the highest rents at £160 per month and unsurprisingly, London was also one of the most expensive spots at £158 per month. Southampton and Cardiff were the cheapest at £82 and £69 respectively.

Steve Barrett from Direct Line points out that it is not surprising that so many people are doing this when the lack of parking in urban areas is such an issue. He says that this practice frees up parking in city centres and ensures the driver a guaranteed space every day.

According to the Ministry of Housing Communities and Local Government, there is no need to apply for planning permission when renting out a driveway or parking spot as long as neighbours are not inconvenienced or other conditions are in place to prevent spaces being used. Anyone planning on doing this should bear in mind that they may need to declare the income and pay tax on it via a Self Assessment.