Use of a 4-year rule building may be unlawful
At first sight, this case is all about the resolution of ambiguity in submitted plans and the admission of extrinsic evidence, but there is an important second point in the decision which gives rise to a degree of concern. This is not to suggest that the judgment is wrong, simply that it could have serious implications. It appears to throw doubt on the lawfulness of the use of a building whose erection has become immune under the 4-year rule. The judge observed that merely because a structure has become immune from enforcement action because it has been in existence for four years does not necessarily mean that any particular use of that structure will also be lawful. The judge pointed out that Section 75 (which provides that a planning permission for the erection of a building may specify the purposes for which the building may be used, and if no purpose is specified then the permission may be taken to authorise the purpose for which it is designed) has no application in relation to a building the erection of which was not authorised by planning permission but has become lawful solely by reason of the 4-year rule.
I am not aware of this point having been raised before, and I think we had all assumed that the lawfulness of the use of a building follows automatically from the acquired lawfulness of its erection, whether by analogy with Section 75 (which the judge quite rightly pointed out clearly does not apply in such a case) or merely as an automatic and previously unquestioned assumption. My initial reaction is that the use of the building does not arise from the making of a material change of use (unless the use of the building can be said to amount to a change of use of the land, which would seem to fly in the face of commonly accepted practice in distinguishing between operational development and a material change of use), but rather from its initial erection. Thus the commencement of the use of the building is not in itself development; it is not a material change of use of the building, because the building (being new) did not have any previous use. The use derives solely from the erection of the building and, I would argue, should therefore benefit from the same immunity as the erection of the building under the 4-year rule. However, the judge’s dicta on the point must inevitably carry weight, and so I suspect this is a topic we shall be revisiting in the future.
There is one other point which puzzled me about the case. I have not had time to go through the judgment with a fine tooth comb, but on a first reading I did not detect any discussion of the identity of the planning unit (the well-known ‘Burdle’ test) and it seems slightly difficult to come to a conclusion on a change of use of the land surrounding a building, unless one can first determine whether or not it falls into one and the same planning unit as the building itself. This aspect of the judgment is difficult to follow, and I shall have to read it more carefully to see if I can unravel this point.