One in 10 homeowners has converted, or is planning to convert, their garage into additional home offices, spare bedrooms and other living spaces - and this social trend could boost the value of British homes by £8 billion, says a new survey.

Research from Santander Mortgages found only a third of homeowners actually use their garage for its designed purpose - storing a vehicle.

Meanwhile, some 1.1 million garage owners have converted, or plan to convert, their garage space to boost the value of their home. One in four has been converted into offices and studios, and nearly half a million into home offices and extra bedrooms.

Nigel Lewis, property analyst at Find A Property, said: "The number of people moving house every year in the UK has halved during the recession.

"Although the market is recovering, instead of selling up and moving on many people are turning to less traditional areas of their homes to create more space for new additions to the family, home offices or space-hungry hobbies.

"Many houses have already had a basement or loft converted and a garage conversion is the next, logical step."

The Santander survey estimates that more than 470,000 garages are earmarked for conversion, with 650,000 already converted.