In May 2025 an application was submitted to Lewisham Council for prior approval of the installation of a 20 metre mast at a sensitive site in Blackheath Conservation Area. The proposal (DC/25/140283) involved siting the mast on the edge of the Heath itself. It was claimed that this involved an innovative design in which the antennas and associated equipment were housed within the mast itself obviating the need for the usual adjoining pavement boxes. Under the amended General Permitted Development Order (2015) Lewisham Council had 56 days from receipt of the application to decide whether to object to the proposal which would otherwise be approved automatically.
The application was rejected by Lewisham and by the Inspector on appeal in what may be regarded as an important, and potentially precedent-creating decision which clarifies the limitations of Permitted Development in respect of applications of this type.
The Blackheath Society and others were minded to object to the proposal but this was not a completely straightforward decision as mobile reception in parts of Blackheath had long been unsatisfactory – something which the mast promised to remedy. However the strength of feeling among residents and (significantly) many local businesses about the visual impact of the mast tipped the balance in favour of objecting.
Objections focused on two principal issues:
· The visual impact of the mast in a highly sensitive part of the Blackheath Conservation Area where it would be in close proximity to a number of nearby listed historic buildings. These issues had all been substantially played down by the applicant.
· The paucity of hard information provided about the likely improvement in mobile reception, the number of customers who would benefit and the feasibility of alternative sites for the mast. It was not possible to form a view about the balance between the visual impact and likely benefits in terms of improved service.
Permission for the mast was refused by Lewisham in July 2025 on the basis of “.. its excessive height and scale, modern appearance and prominent siting at the entrance to Blackheath Village [which] would give rise to an overly dominant, visually intrusive and discordant form of development that would erode the transition between the built form of the Village and the openness of the Heath, detracting from the public realm and historic townscape of the surrounding area. The development would therefore fail to preserve both the character and appearance of the Blackheath Conservation Area and the setting and significance of the surrounding listed buildings.”
The applicants took the matter to appeal. In a complex decision notice issued on 23 December 2025 (APP/C5690/W/25/3373749) the appeal was dismissed on the following broad grounds:
· The design of the monopole, which “would introduce a stark, incongruous and dominant vertical feature into the local area”.
· It would have a detrimental impact on the character and appearance of the Conservation Area and on the significance of nearby Grade II listed buildings.
· Information about basis on which alternative sites had been discounted was deficient so that the reasons for the applicants’ conclusion that the appeal site represented the only viable option could not be accurately assessed.
This was a welcome decision which helps to clarify the limits to the Permitted Development Order in conservation areas while also demonstrating that applicants need to provide rigorous and verifiable data to support any case that the chosen site is the only viable one.
Blackheath Society
June 2026