Since the Supreme Court Judgement in the Hillside case was issued at the beginning of the month, there have been a number of briefing notes prepared and online sessions debating what are clearly potentially significant implications for clients in taking forward existing complex permissions where original proposals have been amended through subsequent S73 or ‘drop-in’ applications and in framing new applications for large sites.

Most will now know the facts of the case and the application(s) it relates to – a full planning permission for the development of 401 dwellings at Balkan Hill, in the Snowdonia National Park, granted in 1967, subsequent amendments resulting in the High Court and most recently Supreme Court judgements.

This note seeks to focus on the key points arising from the case and considers how developers should move forward with multi-unit planning applications in the ‘post-Hillside’ world. Pegasus has received group-wide briefing on the implications of the case from Killian Garvey (barrister from Kings Chambers) and these notes reflect these discussions.

  • The Pilkington Principle – the judgment reaffirms and clarifies the Pilkington principle – that in the event of inconsistent planning permissions, development cannot be carried out under one consent if it cannot be delivered in accordance with its terms and it is physically impossible to complete the development. The departures required to render compliance with that earlier permission “physically impossible” must be “material in the context of the scheme as a whole”. So, the effect of the new consent on the original must be material not just minor amendments.
  • Unlawfulness of development that has taken place – the Supreme Court took a pragmatic view that failure to complete a development for which permission had been granted does not make the development already carried out unlawful. However, on implementation of a drop in consent, further development carried out under previous permissions may not be lawful.
  • Severability – the judgment advises that a planning permission for a multi-phase development is unlikely to be interpreted as severable into a set of discrete permissions, unless there is a ‘clear express provision making it severable’.

So, What Should you Do?

The case has potentially far-reaching implications and these will be played out and clarified as the industry seeks to deal with the implications for specific existing or new planning applications.

The Supreme Court concluded that despite the limited power to amend an existing planning permission, there is no reason why an approved development scheme cannot be modified by an appropriately framed additional planning permission which covers the whole site and includes the necessary modifications.  The position then would be that the developer has two permissions in relation to the whole site, with different terms, and is entitled to proceed under the second.  The submission of an application for the whole site to secure required amendments raises obvious issues pertaining to costs and timing.

We would offer the following headline advice.

For existing consents – where you are looking to amend an approved scheme, carefully consider whether the proposed amendments are material and would render it physically impossible to complete the development under the terms of the original consent. The benefits of the changes against the likely costs should be judged carefully. It may well be that to avoid the ‘Hillside’ risks, a new application for the whole site may need to be pursued.

For new multi-phase developments – it will be important to ensure that any consent provides clear express provision making the various elements severable – most likely through a condition and a phasing plan. Our discussions with Killian Garvey suggest that this may have to go as far as including the term ‘severable’ in any condition and listing out the various different ‘severable’ elements of the scheme for the avoidance of any doubt.

The implications will vary on a case-by-case basis. We can provide more specific advice where required.

A recent appeal (reference 3304168) saw a development for 71 dwellings dismissed owing to the implications from Hillside. Thus, this matter is already generating a lot of attention.

For more information on this note please contact: