The LGA, which represents councils, said it is concerned that rural areas could be missing out on essential local services as a result.
According to the latest figures, 734 homes in England were created as a result of agricultural to residential conversions in 2019-20 under permitted development rights (PDR), which allow developers to bypass the planning system, compared with 226 in 2015-16.
As these properties do not need full planning permission, developers are not required to contribute towards local infrastructure, such as roads, schools and GP surgeries, nor do they have to provide any affordable housing.
Devon saw the highest number of agricultural buildings turned into homes in 2019-20, with 127, followed by Dorset (73), Kent (68), Northamptonshire (33) and Essex (30).
The association has called on the government to revoke the nationally prescribed PDR, which has also been used to convert nearly 65,000 homes from offices since 2015-16.
It reported that this could have led to the loss of more than 16,000 affordable homes, and warned that residents are unable to have their say on these conversions to ensure they meet high standards and are sustainable and suitable for the local area.
The LGA said that communities having a say on individual planning applications is an integral part of ensuring a locally-led planning system.
David Renard, housing spokesperson for the LGA, said: “Councils are absolutely committed to working with the government to build the housing the country desperately needs.
“However it is a growing concern that we are seeing more and more barns and farm buildings in rural areas turned into homes without planning permission.
“Residents in any area need to have the support of strong infrastructure in place, whether that is schools, surgeries or adequate road networks.
“If developers are not obliged to provide any of these, then there is a real risk some communities could miss out on these vital services.
“This is why it is really important that all new housing developments go through a locally-led planning system, so these checks can be made, with the oversight of local communities.
“This needs to be at the heart of the government’s planning reforms, as we await the detail of its Planning Bill later this year.”
