Design and Access Statement in Support of Planning and Listed Building Applications for 16 Halsey Street London SW3 2QH

Transcription

1 Threefold ArchItects Design and Access Statement in Support of Planning and Listed Building Applications for 16 Halsey Street London SW3 2QH 01 Introduction 02 Basement 03 Lower ground floor 04 Upper ground floor 05 first, second & third floors 06 closet wing extension 07 pre-planning feedback 08 HERITAGE IMPACT ASSESSMENT 09 PLANNING POLICY FRAMEWORK Prepared for RBKC Planning Department, 28th August

2 01 INTRODUCTION This document describes the proposed changes to a listed building in a conservation area. Planning permission and Listed Building Consent is sought to alter the building at 16 Halsey St. The private house, a Grade II listed building, is set within a terraced row on Halsey Street, located in the Chelsea conservation area in the Royal Borough of Kensington and Chelsea. The house, built in the mid nineteenth century, comprises of a lower ground floor, upper ground floor, first floor, second floor and third floor located within a non-original mansard roof. There is a light well to the front of the property with a storage room beneath the front entrance steps and a coal cellar beneath the pavement. The property has a garden to the rear which is raised approximately 900mm above the level of the lower ground floor. The nonoriginal conservatory extension to the rear is not of good quality and the heavily expressed fenestration detracts from the original rear aspect of the house. Our aim is to restore the remaining original features of the house such as the stair, plaster mouldings, skirting boards and dado rails and to carry out a general refurbishment and renovation on all floors whilst being mindful of preserving the positions of original walls. We propose to remove all existing laminate flooring on the ground and lower ground and carpeting to the upper floors, replacing it with high quality hardwood flooring, natural stone finishes and carpets respectively. All bathrooms will be fitted with natural stone or porcelain tiled flooring. Underfloor heating will be installed to the lower ground and basement floors. with minimal enlargement, towards the garden. In addition we propose the reinstatement of stepped access from upper ground floor balconette to garden, which will reduce the net volume of the extension. We propose that the closet wing be extended vertically to the third floor where there is currently no closet wing extension, and that the closet wing is extended towards the garden on all floors. The proposal also includes the formation of a new basement beneath the garden which is compliant with LDF Subterranean Development SPD. The external access into the building will remain unchanged from street level. Above - birds eye view looking east; below - photo of front of property No. 19 Closet wing extension to garden- approx. 2.2m No 18 Closet wing extension to garden- Permitted 2006 No 17 Closet wing extension vertically No 16 Halsey Street with original closet wing & non-original rear extension No 15 Four storey infill extension in line with closet wing extension of no. 16 No 14 Closet wing extension vertically & to garden - approx. 2.5m No 12 Closet wing extension vertically & to garden - approx. 2.2m Non-original baffles to tops of windows The proposal seeks to take down the existing late 20th century conservatory and replace with a light weight, high quality structural glass construction Coal cellar below pavement to the front of the property

3 02 Basement The basement design has been prepared with reference to the LDF Subterranean Development SPD, adopted May 2009 The proposal has been designed in view of the following key requirements: 1m of permeable soil above the top cover of the proposed basement. No more than 85% coverage of the garden space (between the boundary walls and existing building) is excavated with the remainder of the space used for drainage, planting and tree pits. It is proposed that the basement would be constructed with a sequence of underpins which would cause no disruption to the neighbouring party walls. It is important to note however that the party fence wall shared with no. 17 is in a poor state of repair and poses a potential hazard both to no. 17 and also to no. 16. Further investigation will need to be undertaken into its structural stability, but it is likely that this wall will have to be taken down and rebuilt as part of the works. The provision of drainage technology to facilitate the movement of water over and around the basement, to ensure it does not collect on the top of the basement and facilitate sustainable urban drainage systems. Extended closet wing Existing non-original french doors replaced with openable door to match the sash window above Steel balustrade to walk-on glass balconette Light wells must not exceed a depth of 1 storey below ground level; be no wider than the width of the existing development; and not exceed more than 1.2m from the external perimeter wall of the above ground building. Excessively large light wells will not be permitted in any garden space. The proposed lightwell meets the above criteria. New sash window to stairwell extension Half-width glazed extension Soft landscaping to garden Geotextile 15% of garden area remains unexcavated 1m A construction method statement has been prepared by a Chartered Structural Engineer and the design has been developed to mitigate against impact on surrounding historic structures and the amenity of neighbouring properties. Modest light well to basement offers light to circulation and habitable spaces Layer of gravel to facilitate free flow of water away from building A sustainability assessment has been undertaken by a Code Assessor and demonstrates that the proposals result in the whole house achieving EcoHomes Very Good standard in accordance with Policy CE1, despite the limitations presented by works to a Listed Building. Sectional perspective of proposed basement

4 03 Lower ground floor The design of the lower ground floor incorporates the feedback we received from our site consultations with planning officers Simon Smith and Barry Valentine and also with the conservation officer Justine Page. These meetings highlighted that we would be required to preserve the original footprint of the back line of the house at Lower Ground Floor. The latest of these meetings highlighted that, under no circumstances, would an alteration to the stair from upper ground floor to lower ground floor be permitted. We have therefore proposed no alterations to this staircase. The existing rear extension is a late 20th century conservatory style addition constructed with timber rafters infilled with double glazing incorporating a door with access to the garden. In accordance with advice from planning and conservation officers the proposal seeks to replace the existing conservatory with a part solid part contemporary lightweight glazed extension which will maximise light levels throughout the (currently) dark lower ground floor, reinstating the solid void massing relationship of the original form at this level. The proposal includes the replacement of the existing upper ground floor solid balconette with a walk-on glass deck. The lightness of the design and removal of the heavy balconette will enhance the reading of the original line of the building. Scale Bar 0m 0.5m 1m 2m 5m Existing lower ground floor plan. Glazing to existing rear extension General notes 1. Dimensioned drawings only. Do not scale. 2. All dimensions and levels to be checked on site prior to commencement of any works, and/or preparation of any shop drawings. 3. Any discrepencies in coordinates, levels, or dimensions and must be reported to the architect immediately. 4. All temporary works to be responsibility of the contractor. 5. This drawing is to be read in conjunction with all relevant Architect s drawings, specifications and other Consultant s information. 6. Threefold Architecture Ltd retain the copyright to this drawing which may not be reproduced or copied without prior written consent. Rev. Date Notes Title Existing Lower Ground Floor Plan Drawing Number Revision 12101_011 Date Scale April :50@A3 Purpose For Information Project 12101_HalseyStreet Client M Mavrakefalos & V Kaeppler Threefold ARCHITECTS Great Western Studios, Studio Alfred Road, London, W2 5EU info@threefoldarchitects.com T Threefold Architecture Ltd. Registered in England & Wales, Company No , Registered Office 601, London Rd, Westcliff-on-Sea, Essex, SS0 9PE Copyright Threefold Architecture Ltd, Scale Bar 0m 0.5m 1m 2m 5m Steps from upper ground floor balconette Proposed line of glazing over stair to basement G D F LIGHT WELL STORE garden access A KITCHEN Restore existing paving slabs and renew existing lightwell doors to incorporate double glazing 4629 A GARDEN 1565 minimal glass balustrading to edge of lightwell void below DINING D LIVING ROOM New link to join these adjoining spaces LARDER WC E 700 UTILITY 1115 Existing garden walls retained Existing conservatory removed and rebuilt with sliding glass rear elevation Line of closet wing extended over Proposed window offers views to garden Line of existing rear walls to be retained General notes 1. Dimensioned drawings only. Do not scale. 2. All dimensions and levels to be checked on site prior to commencement of any works, and/or preparation of any shop drawings. 3. Any discrepencies in coordinates, levels, or dimensions and must be reported to the architect immediately. 4. All temporary works to be responsibility of the contractor. 5. This drawing is to be read in conjunction with all relevant Architect s drawings, specifications and other Consultant s information. 6. Threefold Architecture Ltd retain the copyright to this drawing which may not be reproduced or copied without prior written consent. Rev. Date Notes E Revised to include updated annotations F Amended for planning 1. Refurbish and repair all existing external windows. Install window draught proofing. 2. External facade to be carefully repaired and repointed as required. 3. All external railings and steps to be repaired and redecorated as required. 4. Remove and replace all existing non-original skirtings and architraves, door frames and doors. All new woodwork to be hardwood. Doors to be panelled. 5. Remove and replace all non-orginal plasterwork and replace with plasterwork to match existing. 6. Level existing floors, replace non-original finishes with cut stone/ceramic tiling to bathrooms, carpets to bedrooms and engineered hardwood flooring. 7. Alteration and replacement of existing mechanical and electrical installations to serve alterations to the building including new hot and cold water, heating, comfort, ventilation, lighting, alarm, access, data cabling, electrical power and waste disposal systems as necessary. 8. New bathroom fittings and finishes throughout. 9. All original lath and plaster ceilings to be retained. All others to be replaced. 10. Underfloor heating throughout Basement and Lower Ground Floors Works to floor shown as indicated: A. Restore/reinstate period skirtings/cornicing/plaster mouldings/dado rail. B. Replace non-original built-in joinery C. Form opening to reinstate access. D. New fitted kitchen. E. Altered staircase. F. New basement/access to new basement. Refer to report and appendices for construction and temporary works details. G. Restore/reinstate period fireplace Title Proposed Lower Ground Floor Plan Drawing Number Revision 12101_101 F Date Scale June :50@A3 Purpose For Planning & Listed Building Consent Project 12101_HalseyStreet Client M Mavrakefalos & V Kaeppler Threefold ARCHITECTS Great Western Studios, Studio Alfred Road, London, W2 5EU info@threefoldarchitects.com T Threefold Architecture Ltd. Registered in England & Wales, Company No , Registered Office 601, London Rd, Westcliff-on-Sea, Essex, SS0 9PE Copyright Threefold Architecture Ltd, Plan from withdrawn planning application ref DPS/ DCS/PP/12/02320 showing altered stair to basement Scale Bar 0m 0.5m 1m 2m 5m Stone paved steps to garden Glass bridge over light well below Sliding glass door for garden access Proposed line of glazing over Reinstate original fireplace Works to this room subject to a planning application to be submitted at a later date garden access D K O DINING G G G LIGHT WELL STORE void below KITCHEN Restore existing paving slabs and renew existing lightwell doors to incorporate double glazing GARDEN minimal steel railings to edge of lightwell D K LIVING ROOM UTILITY WC M L H Existing garden walls retained Rear wall Sash window to extension wall in response to advice from planners Line of extended closet wing over Proposed new opening provides stair access to rear of house Remove non-original timber mouldings Existing rear walls to be retained Restore original stair and retain original features Restore existing architraves to doors Remove non-original timber mouldings Carry out damp-proofing to existing coal cellar General notes 1. Dimensioned drawings only. Do not scale. 2. All dimensions and levels to be checked on site prior to commencement of any works, and/or preparation of any shop drawings. 3. Any discrepencies in coordinates, levels, or dimensions and must be reported to the architect immediately. 4. All temporary works to be responsibility of the contractor. 5. This drawing is to be read in conjunction with all relevant Architect s drawings, specifications and other Consultant s information. 6. Threefold Architecture Ltd retain the copyright to this drawing which may not be reproduced or copied without prior written consent. Rev. Date Notes E Revised to include updated annotations F Amended for planning G Amended for planning H Amended for planning I Reduced closet wing extension J Amended for planning K Amended for planning 1. Refurbish and repair all existing external windows. Install window draught proofing. 2. External facade to be carefully repaired and repointed as required. 3. All external railings and steps to be repaired and redecorated as required. 4. Remove and replace all existing non-original skirtings and architraves, door frames and doors. All new woodwork to be hardwood. Doors to be panelled. 5. Remove and replace all non-orginal plasterwork and replace with plasterwork to match existing. 6. Level existing floors, replace non-original finishes with cut stone/ceramic tiling to bathrooms, carpets to bedrooms and engineered hardwood flooring. 7. Alteration and replacement of existing mechanical and electrical installations to serve alterations to the building including new hot and cold water, heating, comfort, ventilation, lighting, alarm, access, data cabling, electrical power and waste disposal systems as necessary. 8. New bathroom fittings and finishes throughout. 9. All original lath and plaster ceilings to be retained. All others to be replaced. 10. Underfloor heating throughout Basement and Lower Ground Floors Works to floor shown as indicated: A. Retain and restore original cornicing. B. Retain and restore matching non-original cornicing. C. Replace non-original cornicing with period-style cornicing to match 'A'. D. Remove non-original cornicing. E. Retain and restore original skirting. F. Retain and restore matching non-original skirting. G. Replace non-original skirting with period-style skirting to match 'E'. H. Retain and restore original dado rail. I. Retain and restore matching non-original dado rail. J. Form opening to reinstate access. K. New fitted kitchen. L. Retain and restore original staircase. M. New basement/access to new basement. Refer to report and appendices for construction and temporary works details. N. Retain and restore exsitng fire surround. O. Reinstate period-style fire place. P. Replace non-original joinery. Title Proposed Lower Ground Floor Plan Drawing Number Revision 12101_101 K Date Scale August :50@A3 Purpose For Planning & Listed Building Consent Project 12101_HalseyStreet Client M Mavrakefalos & V Kaeppler Threefold ARCHITECTS Great Western Studios, Studio Alfred Road, London, W2 5EU info@threefoldarchitects.com T Threefold Architecture Ltd. Registered in England & Wales, Company No , Registered Office 601, London Rd, Westcliff-on-Sea, Essex, SS0 9PE Copyright Threefold Architecture Ltd, Lower ground floor plan submitted as part of this planning application. This takes into account all feedback we have received from the planning and conservation officers. The proposed replacement conservatory has been reduced in size and is not fully glazed. The existing stair from upper ground floor to lower ground floor remains unaltered. The existing laminate flooring and porcelain tiles will be replaced throughout with a high quality stone finish

5 04 UPPER ground floor Following our meeting with the conservation officer on site, we propose to reinstate an opening between the hallway and the front half of the living room and to restore existing original skirtings, dado rails and plaster mouldings. We are proposing to replace the nonoriginal double french door to the rear balconette with a bespoke single door designed with more delicate fenestration to compliment and echo the large but delicate sash window to the existing bathroom directly above. Stair to first floor The non original alcove joinery to either side of both chimney breasts will be replaced with high quality joinery to compliment the rest of the house. The existing fireplace will be replaced by a more suitable period piece, but the original surround will be restored. Above left - existing stair to lower ground floor. Following advice from RBKC planning, it is proposed that this stair be retained Below left - existing french doors to upper ground floor balconette; above right - proposal to alter existing french doors for window as floor above The non original laminate floor finishes will be removed and replaced with a high quality hardwood flooring. OUTSIDE REPLACE DOORS BELOW WITH OPENING DOOR TO MATCH THIS STYLE INSIDE

6 05 First, second & third floors Other than the addition of the extended closet wing, the internal alterations to these floors is minimal. The proposal is to restore all remaining original skirtings, dado rails and plaster mouldings and to replace those that are non-matching and non-original with skirtings and mouldings to suit the property. Non original fitted joinery is to be removed and new high quality joinery will be installed as shown on the drawings In order to provide access to the new closet wing extension on the landing between the second and third floor extension we are proposing to make slight alterations to the non-original stair which links these two floors.

7 06 Closet wing extension AND CONSERVATORY We are proposing to extend the closet wing both vertically and in plan. PP/12/00225 which was granted a 1.4m extension on 26th April This extension is modest in comparison to the numerous, far larger extensions elsewhere in the terrace The proposal seeks to add a storey to the closet wing terminating it below the main parapet by 2 brick courses in accordance with the advice received in pre planning feedback. The massing diagrams opposite and the photograph of the rear of Halsey St on Page 2 of this report show the closet wings at No s 14 and 17 have previously been raised to the parapet level. Furthermore at the neighbouring property No. 15 a nonoriginal extension infilling the space between the closet wings of No s 15 and 16 has been constructed and rises to the top of the mansard roof. This results in a non typical condition creating a flat cliff like rear to the terrace across these 2 houses. The design proposes extending the closet wing towards the garden by 1.4 m in accordance with the advice received from RBKC planning department. This will restore the original pattern of closet wings and light wells to the rear of the terrace. The pre-planning feedback and the subsequent meetings we have had with RBKC planning and conservation (ref: L-PP) support our proposal to extend the closet wing: The established character of the rear elevations of this section of Halsey Street comprises a strong rhythm of closet extensions with modest conservatories. It is noted that the adjoining property at no. 15 has a full width [extension]... resulting in a cliff like appearance. The proposed extension will restore the rhythm of closet wings thereby enhancing the character of the Chelsea conservation area. The size of the extension has been derived from the planning precedent of no. 21 ref: The existing shallow closet wing combined with the infill next door gives rise to this gap in the pattern when the terrace is viewed as a whole. The proposed enlargement of the closet wing reinstates a rhythm to the street, thereby enhancing the character of the conservation area. All additions to the closet wing propose to use reclaimed bricks to match, and where possible to reuse the bricks from the existing wall as part of a high performance insulated construction to significantly improve the energy performance of the external fabric of the building in this area. It is proposed that, where possible, the existing windows will be reused and reinstated in the same positions in elevation. Outside the existing non original lower ground floor extension is an excavated light well area, the footprint of which has been reduced in this proposal. Upon the advice of RBKC, the scheme seeks to replace the non-original extension with a half-width lightweight structural glass enclosure. The proposal looks to remove the existing solid balconette outside the ground floor and replace it with a glass deck. It is proposed that the remainder of the extension be replaced with brickwork built out to a width which corresponds to the width of the closet wing above. The proposed minimal glazed enclosure will give rise to an enhanced reading of the rear of the listed building, improving the view of the garden from the ground floor. In comparison to the conservatory it is replacing the proposed glazed enclosure is smaller in volume, lower than the original at the junction with Cliff-like face Existing massing diagram Restores rhythm of rear closet wings Half-width brick extension Half-width glass extension Proposed massing diagram Existing solid balconette Large area of glazing reflects glare to neighbours Large cut out to garden Reduced area of glazing reduces glare to neighbours Garden level extends to glass extension at this on one side to allow for stair access to basement Proposed metal balconette and stair with glazed risers

8 the existing building and is lighter, as the solid framing is removed. The replacement is of a significantly superior specification and improves the energy performance of the building. Concern has been expressed by neighbours about the possiblility of glare from the new glass extension. The rear of the building is south facing. The angle of the existing conservatory glazing is such that the sun s rays can be reflected back to the neighbouring properties. The orthogonal orientation of the proposed new glazing is such that there will be no sun angles at which the neighbours will be exposed to glare from the new extension. See existing and proposed massing diagrams. The proposed extension offers significantly lower areas of glazing than the existing extension.

9 Location: 16 Halsey Street Job No: 3141 Trial Pit No: Kensington, London SW3 4 Weather: Internal Excavation Method: Hand tools Drawn by: JG Checked by: ME Location: 16 Halsey Street Job No: 3141 Trial Pit No: 1 Kensington, London SW3 Weather: Internal Excavation Method: Hand tools Drawn by: JG Checked by: ME 07 PRE PLANNING FEEDBACK A pre-planning enquiry - case no L-PP - was made on 10th March 2012 outlining the initial proposed works to 16 Halsey Street. A site meeting was held with Simon Smith, planning officer and Justine Page, conservation officer to discuss the proposals. A response was received 9 weeks after submission. We have altered our design proposals in response to their verbal and written feedback and in response to subsequent feedback we have received from RBKC:...an additional storey which is kept at least two brick courses below the eaves of the main house is considered acceptable. Our drawings reflect this requirement. All original walls of historic significance must be retained...floor levels should not be changed and any doors not needed should be retained and fixed shut rather than removed Our drawings reflect this requirement. The existing plans should show the original features of the house... including windows, shutters, architraves, doors, cornices, skirtings and fireplaces and any other features of significance. A separate document, accompanying this application, has been prepared in respect of the above requirement. The following feedback however conflicts with the site conditions: In terms of the closet wing, this could be extended by no more than 1.4m to align with the others in the group. As previously mentioned, other closet wings within 3 houses of no. 16 Halsey Street have been extended by up to 2.5m. Nonetheless we have reduced the proposed extension to 1.4m. The closet wing is visually at the end point of the rear elevation and there should be no further projection outwards from this building line. The existing conservatory extension is full width and currently extends beyond the line to which the closet wing would be extended. In our meeting, RBKC confirmed that the conservatory extension could be extended beyond the line of the extended closet wing. Any extension must be set back from the end of the closet wing by 750mm to preserve the recessed element of the house. As above. In order to safeguard the listed building, the subterranean room should be constructed 500mm clear of the foundations of the house and garden walls. The soil investigation report assessed the condition of the existing foundations to the rear of the property. The results opposite clearly indicate the presence of existing concrete underpins/foundations to the base of the existing (previously external) walls to the rear of the house (see TP1 Section A & TP4 Section A opposite). This is a condition which is also echoed where other internal walls of the house bear onto the ground (see TP5). The presence of concrete provides evidence that the original foundations have either been underpinned or the rear of the house was at some point rebuilt. The former is likely to be the case. In light of the following extract from the subterranean SPD, we feel that this evidence is supportive of our client s proposal to directly underpin the foundations to the rear of the house: Chelmer Site Investigations Unit 15 East Hanningfield Industrial Estate Remarks: Key: Old Church Road, East Hanningfield, Essex CM3 8AB D Small disturbed Telephone: sample Fax: 01245J Jar sample info@siteinvestigations.co.uk B Bulk disturbed Website: samplewww.siteinvestigations.co.uk V Pilcon Vane (kpa) U Undisturbed sample (U100) M Mackintosh Probe Client: Webb Yates Scale: N.T.S. N Sheet Standard No: Penetration 1 of 1Test Blow Count Date: W Water Sample Location: PLASTER BRICK FOUNDATION 500 DM 50(50) 50(20) TDTD Halsey Street Kensington, London SW3 SKIRTING BOARD D SECTION - (A) TP4 (SECTION A) - ENDS AT 700mm Basement level WOOD FLOOR POLYSTYRENE MADE GROUND: medium compact to compact mid brown gravelly silty fine sand with brick and concrete fragments. No roots observed. Suspect MADE GROUND: medium dense to dense mid brown gravelly silty fine sand. No roots observed. Job No: 3141 Trial Pit No: Weather: Internal Excavation Method: Hand tools Drawn by: JG Checked by: ME PLASTER BRICK FOUNDATION SKIRTING BOARD DM 50(20) 50(05) TDTD D TP5 ENDS AT 770mm 5 Basement level WOOD FLOOR SLAB MADE GROUND: medium compact to compact mid brown gravelly silty fine sand with brick and concrete fragments. No roots observed. Suspect MADE GROUND: medium dense to dense mid brown gravelly sandy silty fine sand. No roots observed. S I C Remarks: BRICK PLASTER FOUNDATION DM 50 50(30) TDTD TP1 A TP1 A TP5 TP5 SKIRTING BOARD SECTION - (A) TP1 (SECTION A) - ENDS AT 700mm Basement level WOOD FLOOR POLYSTYRENE BOARD MADE GROUND: medium compact to compact mid brown gravelly silty fine sand with brick and concrete fragments. No roots observed. MADE GROUND: medium dense to dense mid brown gravelly silty fine sand. No roots observed. LOWER GROUND FLOOR CONSERVATORY Key: D Small disturbed sample B Bulk disturbed sample U Undisturbed sample (U100) N Standard Penetration Test Blow Count CLOSET WING TP4 A J Jar sample V Pilcon Vane (kpa) M Mackintosh Probe W Water Sample TP4 A

10 ...the excavation and construction of new foundations may have consequential effects on historic foundations which may impact upon the future stability of the parent building and any adjoining listed buildings. See below for a response from the structural engineer. We have suggested that the front wall of the basement sits beneath the rear wall of the house. In our opinion founding beneath the existing footings is preferable to founding adjacent to them as the excavation of a series of retaining wall sections in these ground conditions would be likely to lead to a progressive loosening of the ground under the footings. The bearing strata in this location is gravel and sand and so ground movements due to moisture variation (associated with clay soils) will not be an issue and so we would not expect founding on different bearing strata to cause relative vertical movements. The building appears to have been constructed circa 1845, long before the common use of concrete in residential foundations. Nevertheless when trial pits have been formed, as part of the exploratory works for this project, concrete footings have been identified. We therefore conclude that the existing building has been underpinned with concrete at some point since its construction. The reason for this underpinning is unclear, however this may have been intended to carry additional load from a mansard roof extension. In some places the original corbelled footings have been removed as part of this work and so we do not believe that this approach will lead to further damage or degradation to the existing foundation structures. The advice in pre planning feedback that...the subterranean room should be constructed 500mm clear of the... garden walls is an onerous requirement given the state of the existing garden walls A site survey found that the garden wall between no. 16 and no. 17 to the north is in a particularly poor state of repair and is on the point of collapse. Given that this existing wall is unsafe and presents a danger to the occupants both at no. 16 and no. 17 our proposal includes to, if necessary, carefully take down and rebuild this existing wall using reclaimed bricks. The basement would be constructed beneath it and that a new wall using reclaimed bricks would then be constructed above using the basement structure as a foundation. The current condition of the boundary wall between 16 and 17 suggest that the wall construction or foundations original foundations to the historic wall may be insufficient and remedial works in the form of underpinning would be recommended to preserve the remaining boundary wall between 14 and 15 and as such the proposal to construct the basement walls by underpinning the garden wall would provide this additional support to preserve this historic structure for the future. In the course of preparing the planning and listed building consent application we have carried out extensive research into the planning precedents of other applications on Halsey Street and have remained informed as to the developments, decisions, amendments and withdrawals of current planning applications. The resulting design has been strongly informed by our observations of recent planning history in the local area and seeks to take on board the information, advice and feedback we have received from RBKC Diagrammatic view of rear as proposed Proposed soft landscaping and border planting New fenestration to match above Glass deck to balconette lightens extension Existing garden walls retained

11 08 HERITAGE IMPACT STATEMENT In the preparation of these proposals careful consideration has been given to the Planning Policy Statement 5 Planning for the Historic Environment The building at 16 Halsey St is located on the eastern side of the street towards the northern end. The terrace is listed as a group and described as being of ample proportions with a frontage in near perfect condition. The Heritage values of Halsey street are largely associated with the public realm and streetscape appearance which is unchanged by the proposals in this application. Halsey street is noted for its three storey brick and stucco terraces, of which the middle and ends of the terrace are defined by pedimented windows, stuccoed quoins and cornices. No 16 does not fall into this group. The notable Heritage values for which this building is statutorily protected are pre dominantly associated with its external features to the front facade, and its relationship to the street. Its original internal features, spatial hierarchy and layout are recognised as being of historical importance, as such any alterations should be of appropriately high quality to respond to the existing fabric of the building. The recognition of the cultural, historic and architectural importance of this building and its group are central to the proposals to enhance and improve the dwelling. The intention of the refurbishment and extension is to safeguard the future of the building and extend its use as a high quality residential building. The proposed internal alterations have no impact on the adjoining properties on Halsey St, and as such have no impact on the special appearance of the conservation area. They are of such a small scale in relation to the conservation area as a whole, as to have no impact on its special character. Original internal features where they remain as identified on the drawings will be repaired, restored and refurbished as appropriate. All non-original finishes and fittings are to be removed and replaced with high quality finishes and joinery as indicated on the drawings. Original fire surrounds will be retained with non original fireplaces and surrounds replaced with new or reclaimed to suit the period and grandeur of the building. All the works of restoration, both generally and in detail, comprise significant enhancements to the special architectural interest of the listed building. The rear of the east side of Halsey st is characterised by a variety of significant alterations and extensions to the rear of the buildings such as to have largely eroded the original form of the rear of the terrace. The proposed alterations to the rear of No 16 seek to reinstate the pattern of closet wings through the extension of the existing closet wing in direct response to the non original full height infill of the lightwell in the adjacent property. In addition a sensitive, part solid, part glazed extension added to the rear in replacement of a non original Victorian conservatory, will reduce the mass at the rear of the building and enhance the reading of the buildings rear form. The replacement of the heavy terrace with a glass deck will improve the light to the lower ground floor rooms. The non original heavily framed french doors at ground floor will be removed and replaced with a single door designed and fabricated to match the existing large panel sash windows above reinstating the original style of fenestration to this opening. These alterations seek to enhance the special character of the building and wider conservation area. External foul waste and rainwater goods will be refurbished or replaced as required with those of matching materials. The proposed basement complies with the latest LDF Subterranean Development guidelines. A minimum of 15% of the existing garden is retained unexcavated and a minimal lightwell is included to a single storey depth to minimise the visual impact of the basement development. A single minimal flush detailed rooflight in the garden to the rear will be all but invisible such as to have no impact on the character of the listed building. In addition the structural design has been developed in direct response to the site investigations and geotechnical information to preserve and protect the future of the existing historic structures. No development is proposed directly beneath the existing Listed Building, where underpinning is proposed beneath the buildings existing underpinned foundations and garden walls it is considered to be a positive design decision to preserve and protect the building and will have no detrimental impact on the existing structures. Taken together the works to the house would not only be of significant benefit immediately to the heritage asset value of the listed building and its setting, but also to its future, and for the benefit of future generations. The setting of No 16 Halsey St would also be significantly enhanced. The improvements to the back of the house will dramatically enhance its appearance from the rear and surrounding buildings, and the character of the building and wider conservation area.

12 09 PLANNING POLICY FRAMEWORK The proposal has been revised following guidance set out in the pre planning feedback letter ref DPS/DC/ PLB/12/0166 Pre3 and in response to advice given in relation to the withdrawn applications ref: In addition reference has been made to the Subterranean Development SPD in preparation of the design proposals. For the reasons given above and set out in detail in this report it is considered that proposals would comply with Core Strategy policies CL1, CL2, CL3, CL5, CL6, UDP policies CD47, CD48 and C63, and the Subterranean Development SPD. DPS/DCS /PP/12/02320 DPS/DCS /LB/12/02321 DPS/DCS /PP/12/02333 DPS/DCS /LB/12/02334 In addition the scheme has been assessed in relation to relevant policies contained in the London Plan and to RBKC s adopted Core Strategy in addition to a number of saved policies within the UDP. The following policies have been referred to in the development of the design and are considered to be relevant to the proposals: CS CL1 Context and Character CS CL2 New Buildings, Extensions and Modifications CS CL3 Heritage Assets - Conservation Areas and Historic spaces CS CL5 Amenity CS CL6 Small Scale Alterations and Additions UDP CD47 Resist Proposals for Extensions UDP CD48 Resist Proposals for Conservatories UDP CD63 Conservation Area views Extensions at the rear are subordinate to the original building and enhance the visibility of the form of the building and thus respect the scale, proportion and character of the existing building, within the context of the individual plot and the wider streetscape. The proposed additions are of a high quality in terms of both aesthetics and function, with respect to qualities of space and light, sustainability and robustness. As such they result in enhancement of the character of the building and area. The enlargement to the closet wing reinstates the rhythm of the building line to the rear thus enhancing the character of the group. The reinstatement of the closet wing relationship between No15 and 16 does not give rise to a worsening of light conditions when taking account of the prevailing general standard. This is considered in addition to the orientation of the rear facade and thus the enlargement of the closet wing does not give rise to the loss of direct sunlight to adjacent windows. It is considered that the proposals would not have a worsening impact on the living conditions of surrounding occupiers. The proposed extensions result in an enlargement of the garden through the reduction of the sunken area directly adjacent to the rear of the house. In addition the proposed replacement extension includes reinstated garden access thus removing the full width nature of the existing conservatory.

13 10 APPENDICES 01_ The Architectural Drawings Site Location Plan 12101_001 Location Plan Plans as Existing 12101_011 B Lower Ground Floor 12101_011a Garden Plan 12101_012 A Upper Ground Floor 12101_013 A First Floor 12101_014 A Second Floor 12101_015 A Third Floor Plan 12101_016 A Roof Plan 02_Structural Engineering Report Engineering Design and Method Statement Geotechnical Report and Survey Structural Engineering Drawings 03_Sustainability and Ecohomes Assessment Ecohomes Assessment Sections as Existing 12101_020 B Section AA 12101_021 B Section BB Elevations as Existing 12101_030 B Front Elevation 12101_031 B Rear Elevation Plans as Proposed 12101_100 H Basement Floor 12101_101 K Lower Ground Floor 12101_101a A Garden Plan 12101_102 J Upper Ground Floor 12101_103 G First Floor 12101_104 G Second Floor 12101_105 G Third Floor Plan 12101_106 A Roof Plan Sections as Proposed 12101_020 E Section AA 12101_021 D Section BB Elevations as Proposed 12101_301 Front Elevation 12101_302 F Rear Elevation