News | December 22, 2022


Last year we reported on a Court of Appeal decision which introduced some uncertainty around the validity of overlapping or ‘drop in’ planning permissions for multi-phased development schemes and also cast doubt over whether development lawfully undertaken in part of a scheme could be subsequently made unlawful if further development was carried out over a remaining part of the scheme not yet built out, under a new planning permission that is not consistent with the original permission. An appeal against that decision has now been rejected, and we now have the benefit of the Supreme Court’s judgment with further clarity on the following points:

  • consistent with the earlier decision, the Supreme Court reaffirmed (in even stronger terms) the Pilkington principle that “a planning permission does not authorise development if and when, as a result of physical alteration of the land to which the permission relates, it becomes physically impossible to carry out the development for which the permission was granted (without a further grant of planning permission)”. The Supreme Court did state that the Pilkington principle should not be interpreted to mean that any departure from the permitted scheme, however minor, will be unlawful and that no further development is authorised unless it complies exactly with what has been approved; this would be “unduly rigid and unrealistic”. They emphasised that the Pilkington principle will apply when the departure from the permitted development is material;
  • addressing the doubt arising from the earlier decision, the Supreme Court held that development that has been carried out pursuant to a planning permission is not rendered unlawful by the failure or inability to complete development or further development under a new, inconsistent planning permission being undertaken over the remaining part of the scheme; and
  • while the Supreme Court’s judgment essentially recognises that ‘drop in’ applications remain a potentially valid avenue by which to seek to vary parts of a larger multi-phase development, the scope of situations where this option can be used appears to have narrowed. For ‘drop ins’ to be possible, the original permission must be capable of being “severed” into separate pieces, and in some cases it may be necessary to submit a new application that covers the entire site to which the original planning permission applies. 

Key points

  • A departure from the permitted scheme will render unlawful the development already carried out due to the undertaking of further complete under a new, inconsistent planning permission.
  • It will be necessary to take greater caution when relying on ‘older’ planning permissions that have been varied over time.
  • ‘Drop in’ applications now have a more limited use and will require particular care.