Going Underground – Basement Excavations and Permitted Development Rights
Many planning authorities, particularly London boroughs, are having to deal with an increasing number of ‘digdowns’, as soaring house prices lead homeowners and developers to increase the value of their properties by extending downwards.
It was previously not clear whether residential basement extensions involving significant excavation works required planning permission or whether such works could be lawfully carried out using permitted development rights. In the absence of guidance, local authorities were taking divergent approaches.
However, in the case of R (Eatherley) v Camden Council 2016, the High Court was asked to consider this controversial question. The owner of a terraced house in north London had been granted a lawful development certificate in respect of the excavation of a 161m² single-storey basement under the footprint of the 128m² house. A neighbour challenged the grant of the certificate on the basis that the development was too substantial to amount to permitted development. The court agreed and quashed the certificate, ruling that the engineering operations constituted a ‘separate activity of substance’ and that Camden Council had failed to consider the nature of the excavation including removal of the ground and soil and the works of structural support.
The judgement has given clarification and much needed guidance to planning authorities. It is likely to lead to an increased number of planning applications in relation to basement projects and more information being required as to the extent of the proposed works.
This is not legal advice; it is intended to provide information of general interest about current legal issues.