West End Square Daylight

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    Daylight, Sunlight and Overshadowing

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    Ballymore Properties Group and Network Rail Contents

    November 2011 gva.co.uk 2

    CONTENTS

    1. Introduction....................................................................................................................... 3

    2. Executive Summary ......................................................................................................... 4

    3. Daylight/Sunlight Planning Principles............................................................................. 5

    4. Assessment Results ........................................................................................................... 9

    5. Summary.......................................................................................................................... 21

    Appendices

    Appendix I Site Location Plan, Tabled Results and Contour Drawing

    Appendix ii Overshadowing Assessment

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    Ballymore Properties Group and Network Rail Introduction

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    1. Introduction1.1 GVA Schatunowski Brooks have been instructed by Network Rail Infrastructure Limited

    and Domain Developments Limited to provide daylight, sunlight and overshadowing

    advice for the redevelopment at West End Lane.

    1.2 We have been provided with a 3D Z map model which shows the bulk/massing of theadjacent properties. We have also been provided with the proposed drawings from

    John Thompson and Partners, drawing reference 00437.

    1.3 We have attended site and reviewed the adjacent properties, counting brick coursesin order to locate the height and locations of the adjacent windows to the

    neighbouring residential properties. We have also sought to obtain layout information

    and elevations for the adjacent properties in order to provide a greater accuracy.

    1.4 For the residential properties to Sherriff Road we have had to make estimates on thelocation of the windows as access to the rear of these properties is restricted and the

    foliage from the trees limits the ability to see all the windows to the rear of these

    properties.

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    Ballymore Properties Group and Network Rail Executive Summary

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    2. Executive Summary2.1 The daylight and sunlight assessments to the neighbouring residential properties have

    demonstrated that there will be a good level of daylight and sunlight retained in the

    proposed condition. The development site currently has low level small buildings and

    therefore a comprehensive redevelopment of this site will reduce daylight and sunlight

    levels when comparing the existing and proposed conditions. However, the daylight

    and sunlight levels in the proposed condition are good levels of light.

    2.2 The overshadowing assessment has demonstrated that all but one of the neighbouringgardens and all the proposed amenity areas pass or exceed the BRE Guidelines,

    ensuring good levels of sunlight will be retained with the proposed development in

    place. The one rear garden that falls below the BRE guideline is mostly overshadowed

    by the assumed 1.8m high solid fence. If the fence were not 1.8m high and of solid

    construction then the garden would pass the BRE guidelines.

    2.3 The internal daylight assessments to the proposed habitable rooms have demonstratedthat a good level of compliance will be achieved with the proposed development

    being in place. In the context of the 435 habitable rooms being provided in thisdevelopment only 0.46% fall below the recommended ADF for their use. We consider

    this is a small proportion in the context of what is being provided and it is not

    uncommon to have some rooms below the BRE Guideline recommendations for high

    density developments.

    2.4 The design of the proposed buildings have allowed light to permeate through so as tolimit the effects of daylight and sunlight on the neighbouring properties, whilst ensuring

    that future occupants within the development obtain good daylight and sunlight.

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    Ballymore Properties Group and Network Rail Daylight/Sunlight Planning Principles

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    3. Daylight/Sunlight Planning Principles3.1 The Building Research Establishment (BRE) guidelines Site Layout Planning for Daylight

    and Sunlight: a guide to good practice is the document referred to by most local

    authorities and the second edition has been produced dated 2011. The BRE Guide

    covers amenity requirements for sunlight and daylight to buildings around any

    development site.

    3.2 The introduction to the guidelines state: -

    "The guide is intended for building designers and their clients, consultants and planningofficials. The advice given here is not mandatory and this document should not be seen

    as an instrument of planning policy; Its aim is to help rather than constrain the

    developer. Although it gives numerical guidelines, these should be interpreted flexibly

    because natural lighting is only one of the many factors in site layout design."

    Daylighting

    3.3 The requirements governing daylighting to existing residential buildings around adevelopment site are set out in Part 2.2 of the guidelines. The amount of light available

    to any window depends upon the amount of unobstructed sky that can be seen from

    the centre of the window under consideration. The amount of visible sky and

    consequently the amount of available skylight is assessed by calculating the vertical

    sky component at the centre of the window. The guidelines advise that bathrooms,

    toilets, storerooms, circulation areas and garages need not be analysed. The guidelines

    also suggest that distribution of daylight within rooms is reviewed although bedrooms

    are considered to be less important.

    3.4 The vertical sky component can be calculated by using the skylight indicator providedas part of the guidelines, by mathematical methods using what is known as a waldram

    diagram or by 3D CAD modelling.

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    3.5 The guidelines states the following:-"If this vertical sky component is greater than 27% then enough skylight should still be

    reaching the window of the existing building. Any reduction below this level should bekept to a minimum. If the vertical sky component with the new development in place, is

    both less than 27% and less than 0.8 times its former value, then occupants of the

    existing building will notice the reduction in the amount of skylight."

    3.6 It must be interpreted from this criterion that a 27% vertical sky component (VSC)constitutes adequacy, but where this value cannot be achieved a reduction of up to

    0.8 times its the former value (this is the same as saying a 20% reduction when

    compared against the existing condition) would not be noticeable and would not

    therefore be considered material.

    3.7 The VSC calculation only measures light reaching the outside plane of the windowunder consideration, so this is potential light rather than actual. Depending upon the

    room and window size, the room may still be adequately lit with a lesser VSC value than

    the target values referred to above.

    3.8 Appendix C of the BRE guidelines sets out various more detailed tests that assess theinterior daylight conditions of rooms. These include the calculation of the average

    daylight factors (ADF) and no sky-lines. The ADF value determines the level of interior

    illumination that can be compared with the British Standard, BS 8206: Part 2. This

    recommends a minimum of 2% for kitchens, 1.5% for living rooms and 1% for bedrooms.

    3.9 The no sky-line, or daylight distribution contour shows the extent of light penetration intothe room at working plane level, 850mm above floor level. If a substantial part of the

    room falls behind the no sky-line contour, the distribution of light within the room may

    look poor.

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    Sunlighting

    3.10 Requirements for protection of sunlighting to existing residential buildings around adevelopment site are set out in Part 3.2 of the BRE guidelines. There is a requirement to

    assess windows of surrounding properties where the main windows face within 90

    degrees of due south. The calculations are taken at the window reference point at the

    centre of each window on the plane of the inside surface of the wall. The guidelines

    further state that kitchens and bedrooms are less important in the context of

    considering sunlight, although care should be taken not to block too much sun. The

    guidelines sets the following standard:-

    "If this window reference point can receive more than one quarter of APSH (annualprobable sunlight hours), including at least 5% of APSH in the winter months of 21

    September and 21 March, then the room should still receive enough sunlight. The

    sunlight availability indicator in Appendix A can be used to check this.

    Any reduction in sunlight access below this level should be kept to a minimum. If the

    available sunlight hours are both less than the amount given and less than 0.8 times

    their former value, either over the whole year or just during the winter months then the

    occupants of the existing building will notice the loss of sunlight."

    3.11 To summarize the above, a good level of sunlight to a window is 25% annual probablesunlight hours, of which 5% should be in winter months. Where sunlight levels fall below

    the suggested level, a comparison with the existing condition is reviewed and if the

    ratio reduction is within 0.8 (the same as saying a 20% reduction) its former value then

    the sunlight loss will not be noticeable. Sunlight reduction that fall below 0.8, i.e. 0.7

    (greater than 20%) then the sunlight losses will be noticed by the occupants.

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    Overshadowing

    3.12 The BRE guideline provides recommendations for overshadowing to gardens and openspaces in Part 3.3 of the guidelines.

    3.13 The guidelines recommend:-It is recommended that for it to appear adequately sunlit throughout the year, at least

    half of a garden or amenity area should receive at least two hours of sunlight on 21

    March. If as a result of new development an existing garden or amenity area does not

    meet the above, and the area which can receive two hours of sun on 21 March is less

    than 0.8 times its former value, then the loss of sunlight is likely to be noticeable.

    3.14 Sunlight at an altitude of 10 or less does not count, because it is likely to be blockedby low level planting anyway. In working out the total area to be considered,

    driveways and hard standing for cars should be left out. Around housing, front gardens

    which are relatively small and visible from public footpaths should be omitted; only the

    main back garden should be analysed. Each individual garden for each dwelling in a

    block should be considered separatelyNormally, trees and shrubs need not be

    included, partly because their shapes are almost impossible to predict, and partly

    because the dappled shade of a tree is more pleasant than the deep shadow of a

    building (this applies especially to deciduous trees). .

    3.15 To summarise, a garden or amenity space should receive at least 50% sunlight for atleast two hours of the day during 21 March. Where this is not achieved in the existing

    condition, a ratio reduction review can be undertaken and if the ratio reduction is 0.8

    or higher (this can also be expressed as 20% or less) then the occupants will not notice

    the sunlight reduction.

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    4. Assessment Results4.1 We set out below the assessments of the neighbouring residential properties, the

    overshadowing effects and the internal daylight/sunlight assessments for the proposed

    habitable rooms.

    4.2 At Appendix I of this report we have appended the tabled results, the no-skylinecontour drawings and 3D views of the development site. At Appendix II we have

    appended the overshadowing analysis. Below is a summary of these results:

    11-77 Sherriff Road (Odd)

    4.3 These properties are located to the south of the development site and we have had torely on the 3D Z map model in order to model the adjacent properties. We have had

    to make assumptions on the location, height and room sizes of these properties as

    access to the rear is restricted. Also due to the distance across the railway line a visual

    inspection of the windows was inconclusive due to the trees and shrubs to the rear of

    each of the gardens.

    4.4 Whilst inspecting the site we noted that the number of storeys for each collection ofproperties and attempted to emulate the number of storeys whilst adopting a rational

    window size and room size in order to give a fair and reasonable indication of the likely

    impact on these properties. We have used the eaves height of the Z map model as

    the control point, taking each storey from the eaves height at 2.8 metres with a window

    of 1.2m high and 1.0m wide.

    4.5 For the purposes of the assessments we have ignored the trees which appear to bepredominantly deciduous. We also note that for 33-77 Sherriff Road that the rear

    extensions to these properties are most likely to be bathrooms or small kitchens. The

    Guidelines state bathrooms need not be analysed as they are not habitable rooms.

    However, for the purposes of this assessment we have assumed that there are

    habitable rooms facing towards the development site to the rear of all these

    properties, which should represent the worst case condition.

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    4.6 We have assessed a selection of properties on Sherriff Street, these being 15a, 19, 27, 37and 47 Sherriff Road. The contour results and location plan can be found on drawings

    BRE/14 and BRE/15 within Appendix 1.

    4.7 The assessment results show that high levels of daylight will be retained in the proposedcondition, in excess of the BRE Guidelines. The design of the proposed buildings have

    allowed light to permeate through so that a good daylight distribution into each of the

    rooms is retained.

    4.8 Sunlight need not be assessed to these properties as the windows are facing north.

    1-12 Aerynn House (Referenced 8a Medley Road)

    4.9 This is a relatively newly built property and we were not able to obtain access into theinner courtyard as the gates onto Medley Road were locked. We were however able

    to obtain access to drawings from the planning portal, drawing reference 10003-P07-13

    from Libero Architects. We have used this information to model the south facing

    windows of this property in order to assess the effects from the proposed development.

    4.10 The first floor level contains the first full habitable floor and therefore this floor level wasused to assess the worse case condition. Drawing BRE/21 shows the contour results and

    location plan at Appendix 1.

    4.11 The VSC assessment results show two windows out of eights, these being windowsW1/380 and W2/380 experience a noticeable reduction in daylight when compared

    against the existing condition. The other six windows exceed the suggested 27% VSC or

    have a reduction in daylight below the suggested 20%.

    4.12 The ADF assessment shows all the rooms will greatly exceed the suggested BREguidelines (bedrooms 1%, living rooms 1.5% and kitchens 2.0%) with ADF values ranging

    between 4.66% and 7.03%, which includes the rooms served by windows W1/380 and

    W2/380.

    4.13 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

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    4.14 The sunlight assessments demonstrate that all the windows will either meet or exceedthe BRE Guidelines in the proposed condition.

    4.15 In summary the occupants of 1-12 Aerynn House will retain a high level of daylight andsunlight, in excess of the BRE Guidelines. The occupants will not experience a

    noticeable reduction in daylight or sunlight with the proposed development in place.

    8-12 Medley Road

    4.16 These properties have an oblique view of the development site and we have modelledand calculated 8 and 9 Medley Road as these are the closest properties to the

    development site. Drawing BRE/20 shows the contour results and location plan at

    Appendix 1. The window sizes and locations to the rear of these properties have been

    estimated as access was restricted but we have sought to represent the worst case

    conditions, assuming habitable rooms at all floor levels.

    4.17 The south facing elevation of 8 Medley Road does not appear to contain anyhabitable rooms, although there are rear extensions set back from the site boundary

    that appear to have windows facing the development site.

    4.18 The VSC assessment results show 8 Medley Road will fully pass, obtaining VSC levels inexcess of 27% or reduction less than 20%. The assessments for 9 Medley Road show

    three of the six windows falling below the 20% reduction test, these being W2/370,

    W2/371 and W2/372.

    4.19 The ADF assessment shows all the rooms will obtain good levels of daylight in theproposed condition with ADF values ranging between 1.46% and 3.40%. The rooms

    served by windows W2/370, W2/371 and W2/372 obtain ADF values ranging between

    1.5% to 1.91%, which meets or exceeds the ADF recommendations for bedrooms and

    living rooms.

    4.20 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.21 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

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    4.22 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

    experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    1-7 Medley Road

    4.23 These properties have windows that take an oblique view across the development siteand we have assessed 7 Medley Road to demonstrate the likely daylight and sunlight

    effects. Drawing BRE/19 shows the contour results and location plan at Appendix 1.

    The window sizes and locations to the rear of this property has been estimated as

    access was restricted.

    4.24 The south facing elevation of 7 Medley Road does not appear to contain anyhabitable rooms, although there is a rear extension set back from the site boundary

    that appear to have windows facing the development site.

    4.25 The VSC assessment results for 7 Medley Road show two of the fifteen windows fallingbelow the 20% reduction test, these being W5/350 and W6/350. All the other windows

    tested will achieve a VSC over 27% or have a reduction in daylight less than 20%.

    4.26 The ADF assessment shows all the rooms will obtain good levels of daylight in theproposed condition with ADF values ranging between 1.52% and 3.95%. The room

    served by windows W5/350 and W6/350 obtain an ADF value of 1.52%, which exceeds

    the ADF recommendations for bedrooms and living rooms. It is most probable that this

    room would not be this size and would be subdivided into smaller ancillary rooms, but

    for the purposes of this assessment we have sought to review a worst case condition.

    4.27 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.28 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.29 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

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    experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    166-184 (Even) Iverson Road

    4.30 These properties are located to the north of the development site with windows on therear elevation facing towards the development site. Drawing BRE/18 shows the

    contour results and location plan at Appendix 1. The window sizes and locations to the

    rear of these properties have been estimated.

    4.31 The VSC assessment results for 178-180 Iverson Road show all the windows will achieve aVSC over 27% or have a reduction in daylight less than 20%.

    4.32 The ADF assessment shows all the rooms will obtain good levels of daylight in theproposed condition with ADF values ranging between 1.65% and 2.68%.

    4.33 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.34 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.35 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

    experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    188-190 Iverson Road

    4.36 These collection of properties are commercial and therefore do not require assessmentwith regard to daylight/sunlight impacts, in accordance with the BRE Guidelines.

    1-28 Rowntree Close

    4.37 These are relatively newly built residential properties that have an indirect view of thedevelopment site. For 6, 14, 21 and 28 Rowntree Close these properties are closer to

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    the development site and have blank south facing elevations with no windows facing

    towards the development site.

    4.38 We have reviewed used the Z map model as a basis, counting brick courses in order tolocate and position the windows. We have assessed the daylight and sunlight results to

    6, 14, 21 and 28 Rowntree Close in order to evaluate the effects from the proposed

    development. These properties are closest to the development site and should

    represent the worst case conditions. Drawing BRE/16 and 17 show the contour results

    and location plan at Appendix 1.

    4.39 The VSC assessment results for 6, 14, 21 and 28 Rowntree Close show all the windows willachieve a VSC over 27% or have a reduction in daylight less than 20%.

    4.40 The ADF assessment shows all the rooms will obtain good levels of daylight in theproposed condition with ADF values ranging between 1.07% and 7.48%. There is only

    one room that obtains an ADF lower than the 1.5% benchmark, this being R2/331 which

    obtains a value of 1.07%. This room is located at first floor level and therefore should

    serve a bedroom. The suggested ADF level for a bedroom is 1.0% so the ADF in the

    proposed condition exceeds this level, passing the BRE guidelines.

    4.41 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.42 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.43 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

    experience a noticeable reduction in daylight or sunlight with the proposeddevelopment in place.

    202-220 Iverson Road

    4.44 These properties are located to the north of the development site with windows on therear elevation facing towards the development site. Drawing BRE/18 shows the

    contour results and location plan at Appendix 1. The window sizes and locations to the

    rear of these properties have been estimated.

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    4.45 It is most likely that the small windows serve non habitable rooms such as bathrooms,which would not normally require assessment. However, in order to provide results we

    have modelled and run assessments, assuming room sizes.

    4.46 The VSC assessment results for 206-208 Iverson Road show all the windows will achieve aVSC over 27%.

    4.47 The ADF assessment shows low levels of daylight due to the small window sizes.However, the existing condition is also very low and the reduction in daylight is not

    noticeable with reductions ranging between 3.17% to 5.23%.

    4.48 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.49 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.50 The daylight and sunlight results show that the proposed development will retain agood level of daylight and sunlight, in excess of the BRE Guidelines. The occupants will

    not experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    Hampstead West 224 Iverson Road

    4.51 This is a collection of commercial properties located to the north of the developmentsite. As these properties are commercial use, daylight and sunlight assessments are not

    required.

    1-10 Redcroft 226 Iverson Road

    4.52 These properties are located on the corner of Iverson Road and West End Lane. Thesouth facing elevation does not appear to contain any residential use or windows that

    need assessing.

    4.53 It is the west facing elevation that is likely to contain residential use, with an obliqueview of the development site. We have assessed the windows closest to the

    development site in order to evaluate the effects from the proposed development.

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    Drawing BRE/16 shows the contour results and location plan at Appendix 1. The

    window sizes and locations to the rear of these properties have been estimated.

    4.54 The VSC assessment results for 1-10 Redcroft show all the windows will achieve a VSCover 27%.

    4.55 The ADF assessment shows all the rooms will obtain good levels of daylight in theproposed condition with ADF values ranging between 2.36% and 2.58%.

    4.56 The No Skyline assessment demonstrates that the occupants of all the rooms will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.57 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.58 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

    experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    124-136 West End Lane

    4.59 At first floor level and above we consider there is residential use and as these windowsface towards the development site, daylight and sunlight assessments were

    undertaken.

    4.60 We have had to estimate the window sizes by counting brick courses and estimatingthe room layouts and uses. We have modelled and tested 130 West End Road with the

    results shown on drawing BRE/16.

    4.61 The VSC assessment results for 130 West End Road show all the windows will achieve aVSC over 27%.

    4.62 The ADF assessment shows the room will obtain a good level of daylight in theproposed condition with an ADF value of 2.77%.

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    4.63 The No Skyline assessment demonstrates that the occupants of the room will notexperience a noticeable reduction in daylight when comparing the existing and

    proposed conditions.

    4.64 The sunlight assessments demonstrate that all the windows will greatly exceed the BREGuidelines in the proposed condition.

    4.65 The daylight and sunlight results show that the proposed development will retain a highlevel of daylight and sunlight, in excess of the BRE Guidelines. The occupants will not

    experience a noticeable reduction in daylight or sunlight with the proposed

    development in place.

    --------------------------------

    Internal Daylight Assessment for the Proposed Habitable

    Rooms

    4.66 The internal daylight assessments have been undertaken for the lowest habitable roomsat lower ground, podium, mezzanine and first floor level. These assessments have been

    undertaken for each building with the tabled results and contour drawings on BRE/01-

    13 at Appendix 1.

    4.67 The Average Daylight Factor tests have assumed a window transmittance value of 0.55which is a greater transmittance value than a standard double glazed unit. This is due

    to the requirement for noise attenuation as the site is next to the railway line. We have

    used an average internal reflectance value for mid range walls, ceilings and floors. For

    living/dining/kitchen areas we consider the ADF level of 1.5% or higher is a good level

    of daylight to be achieved.

    4.68 The proposed internal assessments have reviewed the Average Daylight Factor, Noskyline and Annual Probable Sunlight Hours. We consider for new developments that

    the Average Daylight Factor test is best qualitative assessment for adequacy and

    summarize the results for each building below:

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    Building A

    4.69 The results to Building A demonstrate that all the rooms pass the Average DaylightFactor test, obtaining an ADF higher than the suggested value for its use.

    Building B

    4.70 The results to Building B demonstrate that one room out of eleven tested falls below theAverage Daylight Factor test, achieving an ADF of 1.05% rather than 1.5% for a living

    room. Of the 75 habitable rooms within Building B only having one room falling below

    the recommended ADF value only equates to 1.33%, with 98.67% compliant.

    Building C

    4.71 The results to Building C demonstrate that all the rooms pass the Average DaylightFactor test, obtaining an ADF higher than the suggested value for its use.

    Building D

    4.72 The results to Building D demonstrate that all the rooms pass the Average DaylightFactor test, obtaining an ADF higher than the suggested value for its use.

    Building E

    4.73 The results to Block E demonstrate that one room out of thirty one tested fall below theAverage Daylight Factor, achieving an ADF of 0.66% rather than 2.0% for a kitchen. Of

    the 91 habitable rooms within Building E only having one room fall below the

    recommended ADF value only equates to 1.10%, with 98.90% compliant.

    Building F

    4.74 The results to Building F demonstrate that all the rooms pass the Average DaylightFactor test, obtaining an ADF higher than the suggested value for its use.

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    Summary of Internal Daylight Assessment

    4.75 The assessments to each block has demonstrated a good level of compliance isobtained and that at the upper floor level total compliance with the ADF test will be

    achieved. In the context of the 435 habitable rooms being provided within this

    development only having two rooms below the BRE Guideline recommendations only

    equates to 0.46%, which also equates to 99.54% of the habitable rooms passing the BRE

    Guideline recommendations.

    --------------------------------

    Overshadowing Assessment

    4.76 The permanent overshadowing assessment results are shown on drawing BRE/22 atAppendix ii. The transient overshadowing images have also been appended to this

    report, showing the sunlight tracking within the assessment month of March.

    4.77 The assessment of the individual gardens is shown on drawing BRE/22, together with areference that correlates to the table below. The assessments to the gardens have

    included a 1.8m high solid fence as from site inspection this appeared to be the casefor the majority of the gardens. The rear gardens of the Medley Road properties were

    not able to be seen due to restricted access.

    Area AssessedProposed % in

    Sun

    Existing % in

    SunArea Assessed

    Proposed % in

    Sun

    Existing % in

    Sun

    1 48.98 49.98 2 49.30 49.30

    3 65.79 67.43 4 60.96 61.05

    5 55.88 58.25 6 54.94 58.84

    7 54.08 58.04 8 54.03 59.00

    9 41.48 50.29 10 34.38 64.23

    11 50.40 50.40 12 40.35 40.35

    13 49.67 49.67 14 34.98 34.98

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    Ballymore Properties Group and Network Rail Assessment Summary

    November 2011 gva.co.uk 20

    15 40.99 40.99 16 52.44 52.44

    17 37.09 37.09 18 38.92 38.92

    19 39.49 39.49 20 40.08 40.08

    21 40.18 40.18 22 40.43 40.43

    23 43.71 43.71 24 46.94 46.94

    25 62.89 62.89 26 53.69 53.69

    27 51.85 51.85 28 52.49 52.49

    29 54.28 54.28 30 49.91 49.91

    31 62.18 62.18 32 41.81 41.81

    33 42.66 42.66 34 41.21 41.21

    35 37.25 37.25 36 28.55 28.55

    37 30.13 30.13 38 50.57 50.57

    4.78

    The overshadowing assessment to the neighbouring gardens demonstrates that onlyareas 3-10 will experience any diminution in permanent overshadowing. Areas 3, 4, 5,

    6, 7, 8 and 9 will have reductions in sunlight that will not be noticeable as they are

    within the 20% reduction when comparing the existing and proposed conditions.

    4.79 Area 10 has a reduction in sunlight below the 20%, when comparing the existing andproposed conditions. The majority of the sunlight obstruction is due to the 1.8m high

    fence and if the fences were lower or has a lattice effect the sunlight penetration

    would pass the BRE guidelines in the proposed condition.

    4.80 We consider the effects of the proposed development would not render the gardenuninhabitable and high levels of sunlight will be obtained at 11am and noon. It is

    noted that the effects of the proposed development is no different to the effect from 1

    Medley Road on the gardens to 176-168 Iverson Road.

    4.81 The transient overshadowing images demonstrate that the proposed podium levelsand play ground areas will obtain sunlight throughout the day, obtaining no

    permanent overshadowing effects.

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    Ballymore Properties Group and Network Rail Assessment Summary

    November 2011 gva.co.uk 21

    5. Summary5.1 The daylight and sunlight assessments to the neighbouring residential properties have

    demonstrated that there will be a good level of daylight and sunlight retained in the

    proposed condition. The development site currently has low level small buildings and

    therefore a comprehensive redevelopment of this site will reduce some daylight and

    sunlight when comparing the existing and proposed conditions. The daylight and

    sunlight assessments to the neighbouring properties have demonstrated that the

    occupants will not experience a noticeable reduction in daylight or sunlight.

    5.2 The overshadowing assessment has demonstrated that all but one of the neighbouringgardens and all the proposed amenity areas pass or exceed the BRE Guidelines,

    ensuring good levels of sunlight will be retained with the proposed development in

    place. The one rear garden that falls below the BRE guideline is mostly overshadowed

    by the assumed 1.8m high solid fence. If the fence were not 1.8m high and of solid

    construction then the garden will pass the BRE guidelines.

    5.3 The internal daylight assessments to the proposed habitable rooms have demonstratedthat a good level of compliance will be achieved with the proposed development

    being in place. In the context of the 435 habitable rooms being provided in thisdevelopment only 0.46% fall below the recommended ADF for their use. We consider

    this is a small proportion in the context of what is being provided and it is not

    uncommon to have some rooms below the BRE Guideline recommendations for high

    density developments.

    5.4 The design of the proposed buildings have allowed light to permeate through so as tolimit the effects of daylight and sunlight on the neighbouring properties, whilst ensuring

    that future occupants within the development obtain good daylight and sunlight.

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    Report

    Appendices

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    Report

    Appendix I

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    Report

    Appendix IIAppendix II

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    March 21 8am

    March 21 9am

    March 21 10am

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    March 21 11am

    March 21 12pm

    March 21 1pm

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    March 21 2pm

    March 21 3pm

    March 21 4pm

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    March 21 5pm

    March 21 6pm

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