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Planning application

15 Sydenham Hill London Southwark SE26 6SH

Awaiting decision Southwark 25/AP/3772 Householder Application

Works: Extension Loft or dormer Small domestic

Read from the description, not a valuation. How we read the register

Still open. Anyone can comment while the consultation period runs, and comments go to the council rather than to us.

Proposal

Single-storey rear extension, side staircase, extension to existing annexe, basement conversion with extension, roof dormers and front boundary treatment.

As published by the council, reference 25/AP/3772

Application record

Reference
25/AP/3772
Type
Householder Application
Status
Under consideration/assessment
Received
22 Dec 2025
Validated
23 Dec 2025
Ward
Dulwich Wood
Parish
Dulwich
Postcode
SE26 6SH

Site history

Applications at this address on the Southwark register

This site has had 10 applications since 2023: 8 approved, 0 refused.

  • 26/AP/2548 Decided

    15 Sydenham Hill London Southwark SE26 6SH

    Non-material amendment to planning permission 25/AP/3772 (Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.) The amendment seeks to remove the approved basement extension and reconfigure the terrace above; remove the approved south side (staircase) extension; replace the approved two side-facing windows within the existing annexe with a single high level window; remove Condition 11 (Basement Impact Assessment); and amend the description of development accordingly, to read as: Construction of single storey rear extension with patio, steps and extended terrace, three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.

    Submitted 26 Aug 2026
  • 26/AP/2227 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of Condition 5 (Detailed drawings) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 10 Sep 2026
  • 26/AP/2254 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of Condition 4 (Material samples) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 10 Sep 2026
  • 26/AP/2074 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 8 (Hedgehog accesses) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions
  • 26/AP/2042 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 3 (Demolition and Construction Environmental Management Plan (DCEMP)) as required by planning permission 25/AP/3772 (amended by 26/AP/2548) 'Construction of single storey rear extension with patio, steps and extended terrace, three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Submitted 13 Jul 2026
  • 26/AP/2075 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 9a (Bee bricks and/or invertebrate hotels) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions
  • 26/AP/2073 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 7a (Bat tubes, bricks or boxes) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026
  • 26/AP/2044 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 6a (Bird boxes) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions
  • 23/AP/1965 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Works to TPO trees:T1 - Cherry tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary re-shaping. The height and basic shape would be retained. It is important to prune branches at convenient growth points rather than an all round reduction or pollarding which is not permitted.T2 - Camellia tree approximately 6m in height: Reduce in height to just below cill level of the front bedroom window and reshape as necessary.T3 - Almond tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary reshapingT4 - Oak tree approximately 16m in height: Crown thin by 20% including the removal of dead wood and necessary reshaping. The height and basic shape should be retained. It is important to prune branches at convenient growth points rather than an all round reduction or pollarding which is not permitted.T5 - Camellia tree approximately 5.5m in height: Reduce all round to a more formal shape including the removal of dead wood.T6 - Magnolia tree approximately 5-6m in height: Reshape to form a more balanced specimen including the removal of dead woodT7 - Two cherry trees approximately 7.5m in height: Lightly thin and reshape to provide more formal specimensT8 - Hornbeam group approximately 9m in height: The height to be reduced from under the Oak canopy and crown thinned by 20% including the removal of dead wood and necessary reshaping.T9 - Yew tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary reshaping. The height and basic shape should be retained.

    Decided 16 Aug 2023 Trees

Timeline

Dates from the published record

  1. 22 Dec 2025

    Received by Southwark

  2. 23 Dec 2025

    Validated

    Checked as complete and ready for consideration.

  3. 10 Aug 2026

    Added to PlanIndex

  4. Decision

    Awaiting decision

    Decision expected by 17 February 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.

    Southwark took a median of 52 days over the applications it decided in the last year.

Cases linked to this one on the register

8 later applications on the register refer to this one:

  • 26/AP/2548 Decided

    15 Sydenham Hill London Southwark SE26 6SH

    Non-material amendment to planning permission 25/AP/3772 (Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.) The amendment seeks to remove the approved basement extension and reconfigure the terrace above; remove the approved south side (staircase) extension; replace the approved two side-facing windows within the existing annexe with a single high level window; remove Condition 11 (Basement Impact Assessment); and amend the description of development accordingly, to read as: Construction of single storey rear extension with patio, steps and extended terrace, three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.

    Submitted 26 Aug 2026
  • 26/AP/2227 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of Condition 5 (Detailed drawings) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 10 Sep 2026
  • 26/AP/2254 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of Condition 4 (Material samples) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 10 Sep 2026
  • 26/AP/2074 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 8 (Hedgehog accesses) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions
  • 26/AP/2042 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 3 (Demolition and Construction Environmental Management Plan (DCEMP)) as required by planning permission 25/AP/3772 (amended by 26/AP/2548) 'Construction of single storey rear extension with patio, steps and extended terrace, three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Submitted 13 Jul 2026
  • 26/AP/2075 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 9a (Bee bricks and/or invertebrate hotels) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions
  • 26/AP/2073 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 7a (Bat tubes, bricks or boxes) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026
  • 26/AP/2044 Granted

    15 Sydenham Hill London Southwark SE26 6SH

    Details of condition 6a (Bird boxes) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Decided 1 Sep 2026 Conditions

Who's behind it

Company information only, from the register and Companies House

PLANSTUDIO ARCHITECTURE Agent, an architecture practice registered in London

Active · incorporated 2017 · London

17 applications on PlanIndex · across 4 councils · 100% granted

Trade members see everything this firm has filed, how it was decided, and get an email the day it files again.

See their track record

Documents

Plans, drawings, consultee responses and the officer's report

30 documents on file for this application

A planning file usually holds the application form, drawings and site plans, consultee responses, the officer's report and the decision notice.

Watch members (£5 a month) open the document list from here.

Open the documents

What happens while it is decided

This application is with Southwark for determination, against a statutory target of eight weeks. Over the last year Southwark decided householder applications in a median of 56 days. More in our guide to how long planning decisions take.

About householder applications

Householder applications cover work to an existing house and its garden, such as extensions, lofts and outbuildings, and cannot create a separate dwelling or change what the building is used for. More in our guide to planning application types.

Nearby applications

Within 0.3 miles

  • 15 Sydenham Hill London Southwark SE26 6SH

    26/AP/2074 Submitted 13 Jul 2026 50 yards away

    Details of condition 8 (Hedgehog accesses) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Granted Conditions Extension Loft or dormer +1 5 docs
    Small domestic
  • 15 Sydenham Hill London Southwark SE26 6SH

    26/AP/2075 Submitted 13 Jul 2026 50 yards away

    Details of condition 9a (Bee bricks and/or invertebrate hotels) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Granted Conditions Extension Loft or dormer +1 5 docs
    Small domestic
  • 15 Sydenham Hill London Southwark SE26 6SH

    26/AP/2044 Submitted 13 Jul 2026 50 yards away

    Details of condition 6a (Bird boxes) as required by planning permission 25/AP/3772 'Construction of single storey rear extension with patio and steps, basement extension to provide indoor swimming pool with terrace atop, south side extension to provide internal staircase to basement and three dormer windows to rear roof slope, remodelling and extension of existing annexe to north side of house, alterations to existing ground floor fenestration, and installation of new front boundary treatment.'

    Granted Conditions Extension Loft or dormer +1 5 docs
    Small domestic
  • 15 Sydenham Hill London Southwark SE26 6SH

    23/AP/1965 Submitted 14 Jul 2023 50 yards away

    Works to TPO trees:T1 - Cherry tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary re-shaping. The height and basic shape would be retained. It is important to prune branches at convenient growth points rather than an all round reduction or pollarding which is not permitted.T2 - Camellia tree approximately 6m in height: Reduce in height to just below cill level of the front bedroom window and reshape as necessary.T3 - Almond tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary reshapingT4 - Oak tree approximately 16m in height: Crown thin by 20% including the removal of dead wood and necessary reshaping. The height and basic shape should be retained. It is important to prune branches at convenient growth points rather than an all round reduction or pollarding which is not permitted.T5 - Camellia tree approximately 5.5m in height: Reduce all round to a more formal shape including the removal of dead wood.T6 - Magnolia tree approximately 5-6m in height: Reshape to form a more balanced specimen including the removal of dead woodT7 - Two cherry trees approximately 7.5m in height: Lightly thin and reshape to provide more formal specimensT8 - Hornbeam group approximately 9m in height: The height to be reduced from under the Oak canopy and crown thinned by 20% including the removal of dead wood and necessary reshaping.T9 - Yew tree approximately 6m in height: Crown thin by 20% including the removal of dead wood and necessary reshaping. The height and basic shape should be retained.

    Granted Trees 6 docs
  • 15A Sydenham Hill London Southwark SE26 6SH

    25/AP/3156 Submitted 30 Oct 2025 50 yards away

    95% historically approved · decision due ~26 Dec

    Alteration to existing front wall and railings and formation of a new domestic car parking area, including the formation of a new crossover

    Awaiting decision Householder 5 docs
    Domestic
  • 15A Sydenham Hill London Southwark SE26 6SH

    22/AP/0118 Submitted 17 Jan 2022 50 yards away

    Sycamore (T1) positioned to the lower rear right hand boundary of the garden - remove. Replace with 14-16cm Gleditsia triacanthos Sunburst.Oak (T2) - positioned reasonably close to the rear right hand side of the garden - lightly thin overcrowded areas by up to 20% including the removal of epicormic and dead wood.

    Granted Trees 11 docs

In Southwark

  • 26/AP/2158 Granted

    7 Alma Grove London Southwark SE1 5PY

    Erection of a rear ground floor side extension with a framed glass roof and bi-folding rear doors. Replacement of windows and door. Alterations to external facade.

    Received 21 Jul, published by the council 25 Jul 2026 Householder
  • 26/AP/2601 Awaiting decision

    49 Henshaw Street London Southwark SE17 1PE

    Demolition of existing rear extension and construction of part single, part two storey rear extension and erection of roof terrace on main roof with balustrades and glazed access hatch.

    2 Sep 2026 Householder
  • 26/AP/2545 Awaiting decision

    76 Shenley Road London Southwark SE5 8NQ

    Construction of a single storey side and rear extension to the rear; construction of a rear dormer roof extension over the main roofslope and the installation of 3x rooflights to the front roofslope.

    Received 26 Aug, published by the council 3 Sep 2026 Householder
  • 26/AP/2533 Awaiting decision

    28 Tyrrell Road London Southwark SE22 9NE

    Construction of rear extension.

    Received 25 Aug, published by the council 28 Aug 2026 Householder
  • 26/AP/2517 Awaiting decision

    65 Calton Avenue London Southwark SE21 7DF

    Construction of a ground-floor side-rear extension with terrace reinstated above; alterations to the rear outrigger, including raising the eaves and ridge, removal of the chimney stack, replacement windows, and installation of two rooflights; enlargement of the existing rear dormer; erection of bin and bike stores in the front garden, together with new landscaping and a front boundary wall; installation of an EV charger to front elevation and removal of existing front porch door; removal of existing garden buildings and erection of a shed, sauna and pergola in the rear garden, together with new landscaping and decking.

    Received 24 Aug, published by the council 28 Aug 2026 Householder