Solution sought for bird damaged thatched barn in Avebury
Protective netting is to be put over the thatched roof of a 17th century barn in Avebury, Wiltshire, to try to stop birds from destroying it.
The roof of the Grade I-listed Great Barn, which is owned by the National Trust, has been damaged by jackdaws since it was re-thatched in 2013.
Ed Coney, who re-thatched most of the roof in that £100,000 project, said the damage was "soul destroying".
The National Trust said a long-term solution was being sought.
"We did the job and were very proud of it and everything was fine, and then slowly it's been pulled to pieces," said Mr Coney.
Thatcher Alan Lewis said: "It is a Grade I-listed barn, the centrepiece of a world heritage site, and it should be reflecting the best in British craftsmanship."
He said birds had only damaged part of the roof that was re-thatched most recently, but they had left alone an older part.
"The National Trust are looking at the effect, that the jackdaws are having pulling straw through the netting onto the surface of the thatch, but I think the cause is somewhere else.
"It may be a difference in quality of the two materials used."
National Trust building surveyor Carl Papierz, said: "We've tried umpteen solutions to the problem... eventually they've all failed.
"I'm beginning to tear my hair out. It's so frustrating."
He said extra netting would be put up over the whole barn "in the next two or three weeks" to protect it.
"We're then open to solutions to find a long term solution and if we find a permanent solution the netting will come down."
The former threshing barn is now used as a museum.