This category of development is based on limbs (i) and (iii) of the GDPO definition of “minor development” :
(i) development of an existing dwelling-house, or development within the curtilage of such a dwelling-house, for any purpose incidental to the enjoyment of the dwelling-house as such;
(iii) the alteration of an existing building where the alteration does not increase the size of the building; ".
NB In line with PPS25, 'householder' development (GDPO limb (i)) will include "sheds, garages, games rooms etc within the curtilage of the existing dwelling in addition to physical extensions to the existing dwelling itself. This definition EXCLUDES any proposed development that would create a separate dwelling within the curtilage of the existing dwelling e.g. subdivision of houses into flats" (PPS25, footnote 7, p7).