A month-long consultation is currently underway on government proposals to ease planning rules for a three-year period on developments, including home extensions of up to 8 metres.
But Lincolnshire County Council has urged district authorities to challenge the plans for a relaxation of the current rules, which allow a 3-4 metre limit on extensions without planning permission.
The County Council is asking its district counterparts to follow the lead of Richmond Council and find ways around the new policy.
Councillor Eddy Poll, Executive Member for Planning, said: “Not only will these changes inevitably lead to more neighbourly disputes, but there’s also a danger that a rash of extensions could increase flood risk in certain areas.
“On top of that, there’s undoubtedly going to be an impact on the Lincolnshire landscape.
“Developments of this size have to be carefully considered, balancing the needs of the local community as a whole. A free-for-all is not the way to go, and we hope that our district colleagues will do everything they can to stop it from happening.”