The latest Association of British Insurers figures show subsidence claims are running at less than a quarter of the 1997 level and are considerably down on l998. Last year, there were 37,000 subsidence claims, in l997 the figure ran to over 160,000.

This year's wet summer means that the downward trend is likely to continue. However, Keith Curling, partner with loss adjuster Carmichael & Company, said: “The figures are certainly down but subsidence, however wet the summer, never goes away completely.”

He believes the strong housing market, allied to surveyors' fears about liability, means that every suspicious crack is treated initially as potential subsidence.

Curling said Britons' “insatiable desire” to grow trees near their properties is potentially a cause for a certain amount of movement. Another concern cited by Curling is that in the great subsidence booms of the past 20 years, a certain amount of poor-quality repair work was done. Moreover, many houses have poor drainage systems which can create problems.

“If you like, while we might not be getting floods of claims, we are getting a steady trickle,” said Curling.

He stresses, however, that many of the properties surveyors suspect to have a subsidence problem turn out to be false alarms.

“More than half of those that are referred to us turn out to be something far less serious.”

Surveyors, Curling argues, are petrified of missing subsidence and being sued, so they refer almost every crack they find as a possible subsidence claim to be dealt with by the insurer.

In these cases, Curling usually suggests a minimum period of six to eight months monitoring to see if there is any real movement, which is usually enough to reassure the home owner.

“Where there is a house sale going on we recommend that the buyer just rolls over the seller's insurance policy so there is no change and the sale can therefore go though,” said Curling.

Sometimes though, there can be problems.

“I had one where a couple was in the middle of a bitter divorce and subsidence was found in the home they were going to sell. The whole case dragged on for a year which didn't please either party as they could not stand each other and each saw the subsidence issue as a deliberately annoying ploy by the other.”

He added: “It got so complicated that at one point the High Court divorce hearing had to be held up while the matter of whether the insurance company accepted liability for damage to the neighbour's wall was cleared up.”

Generally, loss adjusters report that not only are the numbers of claims down but so is their average value. Settlement costs are down on average by as much as 20%. However, there is some evidence that whereas claims have always been associated largely with the south there are now more claims coming from the north and Midlands, said Curling.