First-floor rear extension at 61 Ashburnham Grove, Greenwich, London SE10

What was proposed

The application proposed a two-metre-deep first-floor rear extension above the existing outrigger, providing a bathroom with a flat roof and matching materials.

“The application seeks planning permission for the construction of a first- floor rear extension. The proposed first floor rear element would be located on top of the existing part-width two storey rear outrigger and would provide a bathroom.”

“ITEM NO: PAGE NO: 6 5.4. The following changes have been made following the refused and dismissed application ref. 24/3012/HD was determined: - Reference to a ground floor wrap-around addition has been removed (this is now proposed to be considered separately and so this application does not relate to the ground floor rear extension).”

Officer report

The site and its setting

The property is a terraced house within a locally listed group and the Ashburnham Triangle Conservation Area, with a private car park behind it.

“ITEM NO: PAGE NO: Includes the Ashburnham Arms (No. 25) which references the Ashburnhams, the landowning family who developed the area known as the Ashburnham Triangle (now a conservation area). The family’s coat of arms is illustrated on the pub sign. Built between 1851-1855 at the same time as most of the street, forms an integral part of the Grove’s townscape in terms of scale, design and materials and is a cherished local landmark.”

“The application site is also located within the Ashburnham Triangle Conservation Area, and the Ashburnham Triangle Article 4 Direction is in place here.”

Officer report

Earlier applications

Earlier proposals included withdrawn applications, an approved window application, and a refused first-floor extension scheme dismissed at appeal.

“Planning application 25/0187/HD was approved on 17/02/2025 for “Replacement of existing front ground floor and lower ground floor timber sash windows with new glazed box sash windows in like for like style; repair and paint timber rear first floor and ground floor windows in like for like style. (Re-consultation - amended description).”

“Planning application 24/3012/HD was refused on 13/11/2024 for “Construction of a first floor rear extension, a single storey rear extension and all associated works.” The application was then dismissed at appeal (ref. 6000081) on 05/06/2025.”

Officer report

What officers recommended

Officers recommended refusal because the three-storey rear addition, flat roof and position would be an uncharacteristic, dominant and harmful addition.

“It is further recognised that the addition results in the modification of the roof form of the outrigger. The host terrace overwhelmingly features rear outriggers that have mono-pitched roof, and a flat roof form harms this consistency found along this side of Ashburnham Grove.”

“ITEM NO: PAGE NO: 14 storey rear outrigger extension along the row of terraces, which are part of the local listing of properties. This example therefore holds limited weight in the consideration of this submission, and as such the proposed first floor extension would constitute a dominant and uncharacteristic addition to the host building, the wider terrace that it forms part of and the conservation area.”

Officer report

What the applicants said

The applicants said the reduced extension would help their growing family, respond to the property’s context and avoid harm to neighbours or the conservation area.

Members’ discussion

Members questioned why the similar proposal was before them, declined a site visit, and found no planning grounds to overturn the officers’ recommendation.

“Members had no questions for the Planning Officer but did express surprise that the Planning Committee was being asked to consider the proposal, whilst slightly altered, that was fundamental the same, proposal as was refused by Officers and the Planning Inspector and still did not meet the development plan. It was further noted that the Councillor who had called in the applications was not in attendance to provide clarification as to the reasons for such.”

“In considering the application a Member put the proposal for a site visit but the majority of Members felt that they had sufficient information within the report and presentation. I t was also noted that the only reason the matter was before Members was due to it being called in by the Ward Councillor and felt that there were no planning grounds to overrule the Planning Officers recommendations.”

Minutes

The committee vote

Members voted unanimously, with five in favour and none against or abstaining, to refuse planning consent.

“The Chair put the officers recommendation to refuse planning consent to the vote with 5 in favour 0 against 0 abstaining…”

Minutes

The decision and reasons

Planning consent was refused because the extension’s height, scale, design and position would harm the host dwelling, surrounding area and conservation area.

“That planning consent for the construction of a first floor rear extension be refuse for the reasons set out in Appendix 2 of the report, by reason of its height, scale, design and positioning, would constitute an incongruous and unsympathetic development which would cause harm to the character and design context of the locally listed host dwellinghouse, the surrounding area, and the Ashburnham Triangle Conservation Area more widely.”

“That the Assistant Director (Planning & Building Control) be authorised to make any minor changes to the detailed reason for refusal as set out at Appendix 2 of the report, where the Assistant Director (Planning & Building Control) considers it appropriate, before issuing the decision notice.”

Minutes