The High Court recently dismissed a claim for judicial review of a decision to grant planning permission and listed building consent for a rear extension to a listed residential dwelling in Cambridge. Jack Parker explains why.
In Buxton v Cambridge City Council  EWHC 2028 (Admin) the decision was challenged on a number of grounds. However, the Judgment is of particular interest in relation to the “reversibility” of works affecting heritage assets.
The extension in this case was designed so that it could be removed without causing damage to the physical fabric of the listed building. The Council had relied on the reversibility of the proposed works, among other factors, in its judgment that the proposed development would not cause harm to the listed building or its setting.
Historic England guidance (Advice Note 2: Making Changes to Heritage Assets) says on reversibility (at para 43):
“The junction between new work and the existing fabric needs particular attention, both for its impact on the significance of the existing asset and the impact on the contribution of its setting. Where possible it is preferable for new work to be reversible, so that changes can be undone without harm to historic fabric. However, reversibility alone does not justify alteration; If alteration is justified on other grounds then reversible alteration is preferable to non-reversible."
The Claimant challenged the decision on the basis that it was not open to the Council to take into account the “reversibility” of the works because the extension was intended to be permanent and there was no prospect of the works being removed.
The Court disagreed (at paras 51 - 52):
It is important to be clear about what reversibility means. […] the word simply means that a something is capable of being reversed, no more and no less. The concept of reversibility does not carry with it any judgement about the likelihood of the reversal taking place. I therefore do not accept that any benefit of reversibility is not capable of having weight in the decision if what is approved is permanent development with no intention of it being removed. If there were no "practical possibility" of it being removed (in other words, if removal were in reality not possible) that would prevent weight being given to this factor, because the development would not then be truly reversible […]
No policy guidance suggests that reversibility is material only if there is a realistic prospect that the development will actually be reversed. All the Council was saying was that the development could be reversed, and it was entitled to take that possibility into account, without assessing how likely reversal actually was. Of course, if the Council had relied on a likelihood of the permitted alterations being reversed, it would have needed some evidence of that. But it did not rely on such a likelihood and so there was no need for such evidence. Reversibility of itself is material.
Therefore, the fact that works are capable of being reversed is relevant to the question of whether the development would cause harm to heritage assets. That is the case even if the development is permanent with no intention of it being removed. However, those involved in such works will also need to be mindful of the fact that if the works would otherwise be harmful (e.g. to the setting of the heritage asset) then, according to the Historic England guidance, the fact that they are reversible would of itself not justify the development.
All of the Claimant’s other grounds were dismissed.