LONDON – Demand for rental homes in Britain grew in the second quarter at the fastest rate in at least a decade as falling property prices and disappearing mortgage deals deterred potential home buyers, the Royal Institution of Chartered Surveyors said Tuesday.

During the three months ended in July, the institution said a survey of residential lettings revealed the largest increase in the number of properties landlords had put up to rent since the study was first carried out 10 years ago.

In total, 37 percent more real-estate brokers reported a rise in the number of completed rental deals than reported a fall, the London-based industry group said.

Would-be buyers are being put off by the fear that the housing market will suffer further price drops in the coming months. That leaves many in rental housing while they wait to buy. The average asking price for homes has already fallen by nearly 5 percent in the last year, according to data published Monday by Rightmove, the country's largest property Web site.

But even those still interested in buying often can't in the current market. Tightening lending criteria resulting from the credit crunch has led to a massive decrease in the number of mortgages available, making it impossible for many buyers to get a mortgage at all.

While demand for rental properties has skyrocketed, the number of properties available for rental has also increased dramatically, as slumping prices and a lack of buyers turn homeowners from selling to leasing.

But the surveyor group found that the increase in properties on the rental market hasn't kept up with the steep rise in demand, and so rental prices are climbing.

“Becoming a landlord is now an increasingly profitable option,” said James Scott-Lee, the group's spokesman.

“However, ever increasing supply could have an impact on rental growth as tenant options increase,” he warned.

That warning tallies with several other recent studies, which have shown – contrary to the surveyors' overall finding – that rents are already sliding alongside house prices because supply is outstripping demand.

The property firm Knight Frank has predicted that rents in central London could fall by up to 5 percent this year because of the large number of “forced landlords.”