The Appeal to the Supreme Court in HILLSIDE PARKS LTD v SNOWDONIA NATIONAL PARK AUTHORITY (2022) UKSC 30 raised issues of importance in planning law about the relationship between successive grants of planning permission for development of the same land. In particular, it concerned the effect of implementing one planning permission on implementing another planning permission relating to the same site. The case was concerned with operational development rather than change of use.
The Supreme Court made from para 19 observations on planning control and planning permissions, the duration of the latter, and the fundamental feature that a planning permission runs with the land. From para 22 the Court considered powers to vary a planning permission; at paras 26/27 the objective interpretation of a planning permission and what documents are significant in that connection, and from para 28 the position in relation to inconsistent planning permissions, and the leading case of PILKINGTON.
The Supreme Court ruled that there is no principle of abandonment. At para 35 they said that they did not accept that the decision in PILKINGTON can be explained on the basis of a principle of abandonment, nor indeed that there is any principle in planning law whereby a planning permission can be abandoned. From para 41, they analysed the PILKINGTON principle. At para 45, they said that in essence, the principle illustrated by the PILKINGTON case 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.
From para 46, the Supreme Court addressed multi-unit developments, and the LUCAS and SAGE cases. The Court said that when permission is granted for a multi-unit development, the permission authorises each stage of that development for so long as it remains practically feasible for the whole development to be implemented. There is no condition precedent or subsequent that the authorisation granted be implemented in full. Where the earlier stages of the development are carried out in accordance with the planning permission which has been granted, the development so carried out is lawful. In the context of this statutory regime, it would make no sense to grant planning permission for the construction of a multi-unit development conditional upon completion of the whole scheme, whether as a condition precedent or subsequent. If completion of the whole scheme was a condition precedent to the permission, it would never be permissible to begin development. Treating completion of the whole as a condition subsequent, such that failure to complete the whole scheme would retrospectively remove permission for what had been built, would be almost equally unworkable. It would create intolerable uncertainty and potential unfairness, not least for parties who purchased complete units. Unless the condition subsequent was precisely defined, it would also be unclear when or whether it would apply in a situation where, for example, the developer ran out of money or simply decided to stop constriction work but it remained physically possible to complete the development. Parliament cannot have intended accrued property rights to be made vulnerable to enforcement action in such circumstances. The analytical error made in the LUCAS case was to fail to distinguish between two significantly different propositions. The first is that, from a spatial point of view, a planning permission to develop a plot of land is not severable into separate permissions applicable to discrete parts of the site. The second is that, from a temporal point of view, development authorised by a planning permission is only authorised if the whole of the development is carried out. The rejection of the second proposition does not undermine the first.
In summary, failure or inability to complete a project for which planning permission has been granted does not make development carried out pursuant to the permission unlawful. But (in 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.
At para 69, the Supreme Court said that the PILKINGTON principles should not be pressed too far. Rightly in the Court’s 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. What is or is not material is plainly a matter of fact and degree.
The Supreme Court’s conclusion, at para 71, on multi-unit developments, was that they agreed with the view expressed by the Court of Appeal that where a planning permission is granted for the development of a site, such as a housing estate, comprising multiple units, it is unlikely to be the correct interpretation of the permission that it is severable.