But values could be lowered by a proposed limitation on selling only to residents of the Dales, said Nigel Foster of regional land agent George F White .
At present, even some fairly large clusters of houses are not listed as specific settlements, so they are not contained within a development envelope, he said.
In these circumstances, gaining planning consent for residential conversion was almost impossible.
“Sedbusk, for example, which is near Hawes, must contain at least 30 houses, but it has never been officially recognised as a village.
“There must be 20 or so similar cases across the Dales,” said Mr Foster.
Under the existing regulations, consent might be given for commercial or office use, but there was limited demand for this in the park, he said.
When the proposed changes are introduced in 2006, the value of affected barns should receive a significant boost, even if buyers would have to be locals.
“We have been selling barns in the Dales with planning permission for £120,000 to £250,000.”
Mr Foster added that agricultural occupancy conditions, which were more onerous than the new occupancy restrictions, knocked about 30% off open market values.
He expected converted properties within the park to sell for only 20% less than they would do outside its boundaries.
• For more on the proposed changes to the Dales‘ local plan, see FARMERS WEEKLY‘s Farmlife, Feb 11-17