Retrospective Approval Secured for Major Green Belt Extension in Runnymede
Planning success in Runnymede securing retrospective permission for a major extension and mansard roof. The complex Green Belt application successfully demonstrated very special circumstances in a highly constrained and sensitive location.
RUNNYMEDESURREYGREEN BELTPLANNING APPROVALS
Andrew Ransome
5/28/20262 min read
In 2008, I successfully successfully secured retrospective planning permission for a substantial extension and roof accommodation in the Borough of Runnymede.
The application related to a large detached dwelling located within the Green Belt and adjacent to the Chobham Common SSSI and Thames Basin Heaths Special Protection Area — a highly sensitive planning context where strict controls apply to new development.
Retrospective Green Belt Application Approved
The proposal sought permission for a significant two-storey side extension together with additional accommodation within a mansard roof structure.
The works created substantial additional living accommodation while matching the architectural appearance and materials of the existing dwelling.
Given the site’s Green Belt location, the key planning issue centred on whether the scale of the extension amounted to inappropriate development and, if so, whether very special circumstances existed to justify approval.
The Council acknowledged that the cumulative increase in floorspace significantly exceeded normal Green Belt extension thresholds. However, the application successfully demonstrated that the specific operational and security requirements associated with the occupation of the estate amounted to very special circumstances sufficient to outweigh policy harm.
Sensitive Planning Strategy in a Highly Constrained Location
The property forms part of the wider Estate, a substantial and secluded estate set within extensive landscaped grounds.
A detailed planning case was prepared addressing:
Green Belt policy considerations;
Visual impact and openness;
The relationship with nearby environmental designations;
Residential amenity impacts;
Security and operational requirements associated with the estate; and
The limited wider visual impact of the extension due to the secluded nature of the site.
Importantly, the Council accepted that the extension would not materially harm the openness or visual amenities of the Green Belt due to its location within the wider estate and the established screening surrounding the property.
Specialist Green Belt Planning Advice
I regularly advises on complex Green Belt developments, retrospective applications, and projects involving sensitive planning designations across London and the South East.
If you require planning advice for a challenging site or retrospective development proposal, contact me for specialist support.
Andrew Ransome MRTPI Email: andrew@adpltd.co.uk | Tel: 01206 242070
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