Amendments have been made to permitted development rights (PDRs) for the change of use of agricultural buildings to residential and commercial uses.
The changes, which come into force from 21 May, have been announced to the PDRs for agriculture, the government confirmed.
Farmers and landowners will now be able to convert agricultural buildings into a higher number of dwellings, and of a greater size.
Buildings will be able to more flexibly be re-used for other commercial uses, in a boost for on-farm diversification.
For farms over 5ha, the permitted development right currently allows the erection of agricultural buildings up to 1000sqm.
This is to be increased to 1500sqm from 21 May. For farms of less than 5ha, the ability to extend existing agricultural buildings will be increased from 20% to 25%.
However, Class Q permitted development rights won’t be expanded to National Parks and Landscapes, the government confirmed.
Responding to the measures, the Country Land and Business Association (CLA) said it had long argued for PDRs to be extended to grow the rural economy.
The group's deputy president, Gavin Lane said: “We welcome the news that farmers and landowners will now be able to convert agricultural buildings into a higher number of dwellings,.
"There is a chronic lack of rural housing and without it, the sustainability and vibrancy of communities up and down the country is under threat."
But he said the move to not expand Class Q PDRs for National Parks and protected landscapes as 'bitterly disappointing'.
Mr Lane said: "A recent CLA survey found that more than half of our members living in protected landscapes wish to convert existing and redundant agricultural buildings that no longer serve their existing purpose, but under current planning rules and restrictions they cannot.
“Allowing the use of Class Q within these areas would enable much needed development and help stimulate growth in the rural economy.
"So many enterprises in rural areas could grow, could create jobs, could expand into new markets, but are being stifled by an archaic planning regime that seems almost designed to restrict our ambition.
"The rural economy is 19% less productive than the national average – closing that gap could add £43bn to UK GVA.”
