SUPPOSEDLY haunted houses in the UK are having thousands of pounds wiped off their value the moment they are investigated for paranormal activity, a researcher has claimed.

Statistician Dr Geoff Ellis said his study into 25 British "haunted houses" sold over the last half-century revealed they lost an average of 17 per cent from their value compared with the sale prices of similar homes nearby.

The study, believed to be the first of its kind in the world, was commissioned by TV channel Really to mark the new series of Help! My House Is Haunted which airs weekly on Fridays at 10pm.

Dr Ellis said his research suggested having a haunted house would knock almost £40,000 off the average UK property price when it came to selling it.

A separate survey of 2,000 Britons found 23 per cent believed their homes were haunted, while 55 per cent said they would be put off buying such a property.