An existing lawful use of an area of land which is authorised by planning permission may be extinguished by the creation of a new planning unit in respect of the relevant land.
Whether or not an occupier of land which is the subject of an enforcement notice has created a new planning unit is a question of fact and degree to be resolved by the primary decision maker and not by an appeal court. The case that follows was an appeal against an enforcement notice made to the High Court.
In Stone & Anor v Secretary of State for Communities And Local Government & Anor  a planning consent, in 2009, gave permission for an identified planning unit which then existed, namely area D.
That planning unit was the basis of the mixed use that was permitted by the planning consent which happened to be a mixed residential use and storage of non scrap vehicles.
Such a mixed use could exist only because there was a residence and residential curtilage forming part of the planning unit.
Later, due to changes on the ground, the house “Cassita” and its residual residential curtilage became a separate planning unit.
The creation of other new planning units involving area D also caused a material change of use of area D from the use permitted by the 2009 planning permission, which was for the storage of non scrap cars together with a residential use, on area D, to the storage of non scrap cars on part of area D, as part of a larger planning unit constituted by areas A, B, C and part of area D.
In short the residential use of part of area D had become the subject of a separate and new planning unit.
As a result of that change of use the right to use area D in accordance with the 2009 planning permission was lost even though one of the two composite main uses of area D continued in the form of the storage on non scrap cars.
Therefore the enforcement notice served by the council on the appellants was upheld.
This blog has been posted as a matter of general interest. It does not remove the need to get bespoke legal advice in individual cases.