The proposed extensions, by reason of their unacceptable height, depth and width, siting, design, size, mass, bulk and form, would represent an unsympathetic, incongruous and visually obtrusive form of development that fails to appear subordinate to the host property to the detriment of the visual amenity of the street scene and the overall setting, character and appearance of the conservation area. The proposal therefore fails to comply with, in particular, Policies 15, 28 and 29 of the Local Plan (2025), the House Extensions and External Alterations SPD (2015), the Twickenham Village Planning Guidance Supplementary Planning Document (2018), the London Plan (2021) and the National Planning Policy Framework (NPPF) (2026).
The application, by failing to provide sufficiently detailed and justified SuDS measures supported by infiltration testing, has not demonstrated that acceptable runoff rates would be achieved by the development in compliance with Chapter 18 of the NPPF (2026), policies SI12 and SI13 of the London Plan (2021) and policy 8 of the Richmond upon Thames Local Plan (2025).
For the avoidance of doubt the Drawing(s) No(s) and Document(s) to which this decision refers are as follows:- Planning fire safety strategy ref.: PFSS-001 Rev A dated 13 March 2026. Structural foundation statement and construction methodology ref.: AB/ 1726~srep 01 dated 20 June 2026. ARBORICULTURAL IMPACT ASSESSMENT & METHOD STATEMENT ref.: 25_5837_11_92 Version 2 dated 6 July 2026. FLOOD MAP LOCATION Plan ref.: 2089-P001 EXISTING PLANS ref.: 2089-P002 EXISTING ELEVATIONS ref.: 2089-P003 EXISTING LANDSCAPE PLAN ref.: 2089-P010 PROPOSED PLANS ref.: 2089-P110 PROPOSED ELEVATIONS ref.: 2089-P111 Rev A PROPOSED LANDSCAPE PLAN ref.: 2089-P130 PROPOSED SUDS PLAN ref.: 2089-P130 – all received 13 July 2026. Structural drawings ref.: L/1726-01, 02, 03, 04 and 07 Rev P1 – received 15 July 2026.
In accordance with paragraphs 38-42 of the National Planning Policy Framework, Richmond upon Thames Borough Council takes a positive and proactive approach to the delivery of sustainable development, by: * Providing a formal pre-application service * Providing written policies and guidance, all of which is available to view on the Council's website * Where appropriate, negotiating amendments to secure a positive decision * Determining applications in a timely manner. In this instance: * The applicants did not seek formal pre-application advice, and the scheme was found to be contrary to policy and guidance, and subsequently refused. The Council is ready to enter into discussions, through the Council's formal pre-application service, to advise the applicants of relevant policy and guidance; and where possible assist in the preparation of a new planning permission. More information on the pre-application service and relevant fees can be found online at www.richmond.gov.uk/pre-application_for_developers.
Understand planning application documents, officer reports and decision notices. Use a reading checklist, document table and worked example to inspect a case.
Understand pending consideration, approved, refused and withdrawn planning applications. Compare status labels and find the documents explaining each outcome.
Read planning drawings, floor plans, elevations and sections. Use labelled diagrams, a drawing comparison table and revision checks to understand a proposal.