Exemption criteria
An exemption may apply to a dwelling that is an annexe to, or within the grounds of, the main dwelling.
The annexe must be unoccupied and may not be let separately from the main property without contravening planning consent. An example of such a dwelling would be a 'granny annexe'.
You need to send a copy of any planning restriction with your application.
Apply for an exemption on an unoccupied annexe to an occupied property