Planners have refused permission for a complex of new retirement homes to be built in the grounds of Ashwellthorpe Hall.
Developers had wanted to demolish offices used as the headquarters of national charity Disabled Motoring UK and replace it with seven retirement properties built around a courtyard.
The Grade II listed South Norfolk stately home with a medieval moat had been unoccupied and neglected until it was refurbished and sold as a private house in 2010.
The latest plans stated offices in the grounds had become too big for Disabled Motoring UK and had been sold in 2018 to applicants Edifices DK Ltd.
But turning the plans down, South Norfolk Council said the scale of the proposed retirement development would result in harm to the character and appearance of the area.
They added: 'There will not be an overriding economic, environmental or community benefit from the proposed development that outweighs the current employment use.'
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