We now have the judgment of the Supreme Court in Hillside Parks Limited v Snowdonia National Park Authority (2 November 2022).
The case concerns the relationship between successive grants of planning permission for development on the same land and, in particular, about the effect of implementing one planning permission on another planning permission relating to the same site.
The facts concerned, in basic summary, a full planning permission for the development of 401 dwellings at Balkan Hill, near Aberdyfi in the Snowdonia National Park, granted in 1967. Development was to be in accordance with a detailed “master plan” showing the proposed location of each house and the layout of a road system for the estate.
Only 41 of the dwellings have been built to date, none in accordance with the masterplan. The developer, Hillside Parks Limited, has applied for and been granted a series of additional planning permissions permitting development which has taken place on parts of the site.
The Supreme Court has followed the Court of Appeal and High Court in concluding that development pursuant to the 1967 planning permission cannotlawfully be continued:
“The courts below were right to hold that the 1967 permission was a permission to carry out a single scheme of development on the Balkan Hill site and cannot be construed as separately permitting particular parts of the scheme to be built alongside development on the site authorised by independent permissions. It is possible in principle for a local planning authority to grant a planning permission which approves a modification of such an entire scheme rather than constituting a separate permission referable just to part of the scheme. The Developer has failed to show, however, that the additional planning permissions under which development has been carried out on the Balkan Hill site since 1987 should be construed in this way. Therefore, that development is inconsistent with the 1967 permission and has had the effect that it is physically impossible to develop the Balkan Hill site in accordance with the Master Plan approved by the 1967 permission (as subsequently modified down to 1987). Furthermore, other development has been carried out for which the Developer has failed to show that any planning permission was obtained. This development also makes it physically impossible to develop the site in accordance with the Master Plan approved by the 1967 permission (as subsequently modified).” (paragraph 100).
Whilst the specific facts of the case are unusual (including a degree of uncertainty as to the intended procedural status and effect of the subsequent planning permissions, several of which on their face are described as “variations” of the 1967 planning permission) the Supreme Court sets down some general principles to be applied to situations concerning overlapping permissions. The judgment clarifies some ambiguities arising from the earlier Court of Appeal judgment, although ambiguities remain.
One ambiguity indeed is as to the extent to which the principles set out apply to outline planning permissions, given passages such as paragraph 20:
“In this case, we are concerned with grants of full planning permission, in relation to which it is to be expected that a reasonable reader would understand that the detailed plans submitted with the application have particular significance.”
On first reading, I draw the following principles from the judgment:
- Approval of the Pilkington principle
“In essence, the principle illustrated by the Pilkington case [ 1 WLR 1527, Divisional Court] is 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) … Where the test of physical impossibility is met, the reason why further development carried out in reliance on the permission is unlawful is simply that the development is not authorised by the terms of the permission, with the result that it does not comply with section 57(1).” (paragraph 45)
“…([I]n the absence of clear express provision making it severable) a planning permission is not to be construed as authorising further development if at any stage compliance with the permission becomes physically impossible.” (see paragraph 68)
- Interpretation of planning permissions for multi-unit developments
A planning permission for a multi-unit development is unlikely properly to be interpreted as severable into a set of discrete permissions to construct each individual element of the scheme.
However, see the reference above to the possibility of “clear express provision making it severable”. An early thought in reaction to the judgment is that in relation to large multi-phased planning permissions this may already be the case. Where it is not, it may often be useful in the future for it to be introduced.
- The whole development is not unlawful if a proposed development cannot be completed fully in accordance with the planning permission
The Supreme Court doubted that it was correct that “in carrying out a building operation, any deviation from the planning permission automatically renders everything built unlawful, even in relation to a single building” and considered that it was certainly not the case that failure to complete a building operation for which planning permission has been granted renders the whole operation including any development carried out unlawful (To that extent the Supreme Court disagreed with remarks of Lord Hobhouse in Sage v Secretary of State for the Environment, Transport and the Regions  UKHL 22).
- Under the Pilkington principle, departures must be material
“The Pilkington principle should not be pressed too far. Rightly in our view, the Authority has not argued on this appeal that the continuing authority of a planning permission is dependent on exact compliance with the permission such that any departure from the permitted scheme, however minor, has the result that no further development is authorised unless and until exact compliance is achieved or the permission is varied. That would be an unduly rigid and unrealistic approach to adopt and, for that reason, would generally be an unreasonable construction to put on the document recording the grant of planning permission – all the more so where the permission is for a large multi-unit development. The ordinary presumption must be that a departure will have this effect only if it is material in the context of the scheme as a whole: see Lever Finance Ltd v Westminster (City) London Borough Council  1 QB 222, 230. What is or is not material is plainly a matter of fact and degree” (paragraph 69)
- How to vary a planning permission
Aside from the specific statutory procedures (section 73 and section 96A – and potentially in due course the additional procedure proposed in the Levelling-up and Regeneration Bill), what else can a developer do where it wishes to depart from the planning permission it has been granted?
“73 … [Counsel for Hillside] also submitted that it would cause serious practical inconvenience if a developer who, when carrying out a large development, encounters a local difficulty or wishes for other reasons to depart from the approved scheme in one particular area of the site cannot obtain permission to do so without losing the benefit of the original permission and having to apply for a fresh planning permission for the remaining development on other parts of the site.
74. In our view, that is indeed the legal position where, as here, a developer has been granted a full planning permission for one entire scheme and wishes to depart from it in a material way. It is a consequence of the very limited powers that a local planning authority currently has to make changes to an existing planning permission. But although this feature of the planning legislation means that developers may face practical hurdles, the problems should not be exaggerated. 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.
75. The Authority has argued that, because the planning legislation does not confer any power on a local planning authority to make a material change to an existing planning permission, a later planning permission cannot have the effect of modifying in any material way the development scheme authorised by an earlier permission.
76. The trial judge, HHJ Keyser QC, did not find this argument persuasive and nor do we…”
If I have this right, this would be a procedure to fall back on in a situation where the Pilkington principle would otherwise bite i.e. where, even though development will be unchanged pursuant to part of the planning permission (1) that part can’t be shown to be clearly severable from the remainder (or presumably amended via section 96A or section 73 so as to be clearly severable) and (2) it would now be physically impossible to complete the planning permission in accordance with its terms (its original terms or presumably as amended via section 96A or section 73) if a separate permission were to be granted in relation to part of the development area covered by the permission.
- No principle of abandonment of planning permissions
The developer’s argument that Pilkington should be analysed as a case resting on a principle of abandonment was rejected. The Supreme Court does not accept “that there is any principle in planning law whereby a planning permission can be abandoned” (paragraph 35).
I hope this brief initial run down is a helpful introduction to what will in due course be a very familiar text for all of us. More anon I’m sure.
Simon Ricketts, 2 November 2022
Personal views, et cetera
Courtesy Mel Poole on Unsplashed