Variation of condition 1 of planning permission dated 16th November 2021 (RN: 21/05242/FULL) for Erection of rear extension, formation of lightwell and associated excavation to lower ground floor level; glazed conservatory at rear ground floor level with associated balcony and stair; partial demolition of existing closet wing and replacement with raised roof level; installation of dormer window, roof light and AC units at roof level and associated works. NAMELY, installation of an alternative air conditioning unit and replacement of its enclosure with an acoustic screen at roof level.

Variation of Condition 1 of planning permision dated 16 October 2023 (RN: 23/05842/FULL), which itself varied planning permission dated 22 December 2022 (RN: 22/06621/FULL) for: Reconfiguration of two residential units to form one unit within Nos. 25, 26 and 48; and new residential unit within No. 49; installation of four condenser units, two on each of the roofs of Nos. 25 and 26; and extension at rear third and fourth floor level of No. 25 and associated works (site includes 25-26 Chester Square and 49-48 Eaton Mews South). NAMLEY, to allow works to front lower ground floor including new York stone paving to lightwell with single step below external staircase, new timber sash window with sidelights, new security railings to both windows in lightwell at no. 25, to match no. 26 existing railings; new York stone paving at no. 26, lightwell, and new Portland stone to both no. 25 and no. 26; rear elevation works include new glazing and glazing bar layout to external door to rear elevation, omit proposed screen between 25 and 26 terraces, new metal railings to coping at no. 25 terrace, and new double dormer; new front door, garage gate and associated fanlights at no. 48.

Variation of condition 1 of planning permission dated 31 May 2023 (RN: 23/01224/FULL) for demolition of existing rear and side extension, and replacement with single storey rear extension (lower ground level), and double storey side extension (lower-ground and ground level), lowering of existing lower-ground floor level, addition of rooflights at ground floor, first floor, and roof level, and updates to existing rear dormer and windows.; NAMELY, for the installation of a rooflight to the side extension.

Variation of condition 1 of planning permission dated 21st April 2022 (RN: 22/00336/FULL) for the Extension to mansard roof and roof terrace, relocation of extract duct to the rear from RN: 22/00336/FULL. Namely, to increase in the overall height of the North elevation dormer windows by lowering the cill level and to increase the size of the roof light above the staircase.

Amendments to planning permission dated 2 March 2022 (RN:21/08243/FULL) for 'Variation of condition 1 of planning permission dated 25th August 2021 (RN 21/03822/FULL) which itself varied condition 1, condition 4 (part a) and condition 5 (parts i, iv and v) and the removal of Condition 4 (parts b and c), 5 (parts ii and iii) and 8 of planning permission dated 3 December 2020 (RN:20/03764/FULL) for 'Removal of existing roof top plant and extension to create an additional storey at fifth floor with tiled mansards and lead clad dormer windows to front and rear; a single storey extension at fourth floor comprising a glazed dome above the existing rear bow; installation of plant at roof level; partial infilling of lightwell adjacent to Gwydyr House; facade cleaning and other facade repairs; and other associated works in connection with the existing use (Sui Generis)'. Namely, amendments to the new fifth floor roof layout and increase front parapet height.

Variation of condition 1 of planning permission dated 15th June 2022 (RN:22/01971/FULL) for the Replacement dormer extension with a larger dormer extension, addition of a new rooflight, replacement and slight enlargement of first floor fenestration to rear elevation and levelling of flat roof above first floor bathroom from RN:22/01971/FULLL. Namely, to reduce the size of some existing windows, the size of the dormer to be retained.

Variation of conditions 1, 4 and 5 of planning permission dated 21 April 2022 (RN: 22/00336/FULL) for the: Extension to mansard roof and roof terrace. Relocation of extract duct to the rear. Namely, to increase in the overall height of the North elevation dormer windows by lowering the cill level; Increase in the width of the South and North elevation dormer windows; Increase the size of the roof light above the staircase; Set back the Southern elevation of the mansard roof and dormer window; Change the mechanism of the rear elevation dormer windows to bottom hung, inward tilting; Change the material for the windows within the dormers to painted metal frames; and introduction of sliding, painted timber solar shading panels.

Variation of condition 5 of planning permission dated 6th August 2021 (RN: 21/07355/FULL) for the rear dormer roof extension and new rooflights, infill extension to ground floor rear; alterations to windows and doors on all elevations. Namely, to allow the installation of openable windows for natural ventilation at first floor side (south) elevation instead of the approved fixed window.

Variation of condition 1 of planning permission dated 23rd August 2021 (RN: 21/04731/FULL) for the: Erection of a single storey rear extension at ground floor level, loft conversion including dormer and rooflights, provision of level access and landscape works to the gardens, and associated works. NAMELY, to retain extended part of rear extension and associated folding doors.

Amendments to planning permission dated 02 March 2022 (21/08243/FULL) for 'Variation of condition 1 of planning permission dated 25th August 2021 (RN 21/03822/FULL) which itself varied condition 1, condition 4 (part a) and condition 5 (parts i, iv and v) and the removal of Condition 4 (parts b and c), 5 (parts ii and iii) and 8 of planning permission dated 3 December 2020 (RN:20/03764/FULL) for removal of existing roof top plant and extension to create an additional storey at fifth floor with tiled mansards and lead clad dormer windows to front and rear; a single storey extension at fourth floor comprising a glazed dome above the existing rear bow; installation of plant at roof level; partial infilling of lightwell adjacent to Gwydyr House; facade cleaning and other facade repairs; and other associated works in connection with the existing use (Sui Generis). Namely, amendments to the abutment of the roof extension with Banqueting House and alterations to the rear part of the mansard roof extension.' Namely, amendments to the new fifth floor roof layout, installation of dry riser inlet, and part cornice removal on rear elevation to facilitate the installation of the consented springing dome; and variation to the wording of condition 3 (materials) to a compliance condition.