Rother District Council distinguishes accommodation ancillary to the main dwellinghouse from a separate home. Its annexe guidance says an annexe will generally require planning permission. Independent occupation, renting, or holiday use requires permission where there is no clear ancillary relationship to the main home.
Separate new outbuildings from existing conversions
The Council says a new garden outbuilding intended as an annexe cannot use permitted development rights under the ordinary Class E route, even if the other outbuilding criteria appear to fit. A conversion of an existing building within the dwelling’s curtilage may be possible without planning permission, depending on the case.
Where the proposed use or planning history is uncertain, the Council identifies a Certificate of Lawful Proposed Use or Development as a way to obtain a formal decision about whether permission is required. The existing-building route is case-specific; it is not a general exemption for every garage or outbuilding.
This guidance applies to Rother District in England. Confirm the current planning history, proposed relationship to the home, local policy, and permission route with the Council before relying on it.