Earlier this month, a court decided that a basement extension could not be lawfully carried out using permitted development rights. There is now concern that the decision in Eatherley v London Borough of Camden could prevent the use of permitted development rights for basement extensions. So does this decision mean that all basement extensions now require planning permission?
If a type of development benefits from permitted development rights, it means that it is, in effect, granted planning permission without having to apply for it. Whilst there is no specific provision for basement extensions in the Town and Country Planning (General Permitted Development) (England) Order 2015, most local planning authorities have treated basement developments as permitted development.
The decision centred around whether the engineering works, which were a necessary part of the basement development, were part of the development, or were a separate activity. The distinction was critical:
The court decided that the local planning authority had asked itself the wrong question when making its decision to grant a lawful development certificate.
Rather than asking whether the engineering works were part and parcel of the making of a basement, the local planning authority should have asked whether the works constituted a separate activity of substance.
To assess this, the local planning authority would have needed to examine the nature of the excavation and removal of the ground and soil, and the works of structural support required. Only after looking at these elements could it decide whether the works amounted to a separate activity of substance, for which planning permission would be required.
It is difficult to see how any basement development could be undertaken without significant engineering works.
The court in this case did not say that engineering works would always constitute a separate activity of substance; it merely decided that the local planning authority had asked itself the wrong question and had not, therefore, looked into the issue sufficiently.
Nevertheless, some have commented that the decision belittles permitted development rights. It remains to be seen whether the decision will be appealed.
Even without an appeal, there are complexities around basement developments.
Given the conditions that have to be met, the various policies that may exist, and the possibility of an Article 4 direction being in place, together with the uncertainty that exists following the decision in Eatherley v London Borough of Camden, and possible changes to the law following the government's review, advice should always be sought from a qualified planning lawyer before embarking on any subterranean development works.
Contributor: Alexandra Holsgrove Jones
This publication is intended for general guidance and represents our understanding of the relevant law and practice as at December 2016. Specific advice should be sought for specific cases. For more information see our terms & conditions.