DAYLIGHT, SUNLIGHT AND OVERSHADOWING
The EXO Building at Point Village
North Wall Quay & East Wall Road,
Dublin 1.
For Grant Thornton, on behalf of the
Specified Assets of Henry A. Crosbie (In Receivership)
DAYLIGHT, SUNLIGHT AND OVERSHADOWING
1. INTRODUCTION
This report comprises an assessment of the likely potential daylight, sunlight, overshadowing impacts
associated with the proposed development of a commercial building of The Exo Building and associated public
realm works, including a Glass Box restaurant café, at Point Village Square, Dublin 1.
It is proposed to develop The Exo Building as a linear building to the east of the former Point Depot, now the
3Arena, and along the East Wall Road. The building will range from 8 to 17 storeys in height, with the taller
element extending into Point Village Square. In addition, a range of public realm works are proposed, including
a Glass Box restaurant/café within Point Village Square which will assist in providing a sense of enclosure along
the eastern side of Point Village Square.
The proposed Exo Building and Glass Box restaurant café are indicated in red on Figure 1 below.
Figure 1: Location of proposed development
2. SUNLIGHT, DAYLIGHT AND OVERSHADOWING
Sunlight, Daylight and Overshadowing assessment is normally carried out with particular regard to potential
impacts on the living spaces and private open spaces of residential properties, but assessments may also
extend to include amenity spaces such as public spaces, parks, playing fields and playgrounds between nondomestic buildings and in streetscapes.
In the case of the proposed development, there are no existing residential properties within the immediate
vicinity. The guidance documents, referenced below, indicate that site specific characteristics be taken into
account when carry out assessments. As such, the locations of the spaces assessed in this report are provided
below in Section 4: Assessment.
Methodology
The assessment of the impacts of the proposed development was prepared using the methodology set out in
BRE 209, ‘Site Layout Planning for Daylight and Sunlight: A Guide to Good Practice’, Second Edition 2011, by P.
J. Littlefair. This is the non-statutory guide referred to in the Dublin City Council Development Plan 2011 – 2017,
and sets out guidelines that are most commonly used in Ireland and the UK to assess the impacts of
development on daylight and sunlight. It provides advisory numerical targets that represent good practice;
however, the location specific characteristics of each site must also be taken into account.
This report uses these guidelines to assess the likely impacts on sunlight, daylight and overshadowing of the
proposed development on nearby properties and public spaces.
It is noted that the guidance is intended to be used in conjunction with the interior daylighting
recommendations in British Standards BS 8206-2 Code of Practice for Daylighting, and in the CIBSE publication
Lighting guide: daylighting and window design. These publications provide specific advice and design
consideration at new rooms and windows which are part of the development, and may themselves be
susceptible to adverse lighting impacts arising from other parts of the same development. The advice in these
publications is not applicable to existing receptors that are outside of the proposed development.
Sunlight
The BRE Report recommends that loss of sunlight should be checked for main living rooms of dwellings, and
conservatories, if they have a window facing within 90° of due south. If the development wholly lies due north,
then sunlight loss need not be analysed.
Sunlight can be quantified in terms of the Annual Probable Sunlight Hours (APSH) for any given location.
Annual Probable Sunlight Hours is the total number of hours in the year that the sun is expected to shine on
unobstructed ground while allowing for average monthly levels of cloud cover for the specific location. The
APSH for any given location depends on its latitude and longitude which determines the number of daylight
hours for any particular location, but also on statistical records for that location which indicates the number
of daylight hours that are likely to experience sunshine.
The number of daylight hours in Dublin ranges from 7hrs 30mins on 21st December to 17hrs 00mins on 21st
June. Over the whole year, there are a total of 4410 daylight hours. In order to determine sunlight hours,
statistical data is available from Met Eireann that identifies the mean daily duration of sunshine for each month
of the year averaged over the 30 year period from 1961 to 1990, recorded at Dublin Airport.
Table A: Average monthly sunshine hours recorded at Dublin Airport from 1960 to 1990
Month
Daylight Hours
Average Sunlight Hours
Factor
January
245.1
55.8
22.80%
February
268.8
70.0
26.00%
March
360.6
111.6
30.90%
April
412.5
156.0
37.80%
May
483.8
189.1
39.10%
June
499.1
180.0
36.10%
July
502.1
167.4
33.30%
August
452.2
158.1
35.00%
September
376.8
129.0
34.20%
October
323.9
96.1
29.70%
November
254.8
72.0
28.30%
December
229.1
52.7
Total
4408.8
1437.8
23.00%
32.60%
Winter
1677.3
465.2
27.70%
While the average percentage of daylight hours likely to experience sunshine is 32.60%, this varies
substantially from just below 23% in January to just over 39% in May.
The BRE Report recommends that the centre of the window, or in the case of a patio door, a point 1.6m above
floor level, should receive at least 25% of the APSH, including at least 5% of the APSH from 21st September to
21st March. If the available sunlight hours become less than this, and less than 0.8 times their former value,
either over the whole year or just in the winter months, then a noticeable loss of sunlight can occur. If the
overall annual loss is greater than 4% of APSH, rooms may appear colder and less pleasant.
For Dublin, 25% of the APSH, totalling 1,438 hours as seen in Table A, equates to 25% of 1438 hours, or 359.5
hours. During winter, from 21st September to 21st March, there should be a minimum of 5% of 1423 hours, or
71 hours of sun.
Annual recommended target
359.5 probable sunlight hours
Winter recommended target
71.9 probable sunlight hours
A Sunpath Diagram is used to calculate the Annual Probable Sunlight Hours for any given reference point.
Sunpath Diagrams are generated for different longitudinal locations using solar data for different days of the
year at times of day. The Sunpath Diagram comprises a ‘plot’ of the path of the sun as ‘seen’ from a particular
location on different days of the year and at different times of the day. Generally, sunlight in the lowest six
degrees of elevation is discounted to take account of existing built or planted obstructions at or near the
horizon. Existing and proposed developments outside the reference point can also be ‘plotted’ onto the
diagram, and the dates and times at which the suns path will be obstructed by these can be determined from
the plots. The Sunpath Diagram provides a numeric value for the total number of daylight hours during each
month during which the sun would not be blocked by any physical obstructions, but assuming an otherwise
unobstructed clear sky throughout all the hours of daylight. This value, together with the statistical factor in
Table A, can then produce the probable sunlight hours for each month, and in turn, for the whole year as well
as the winter months. Brady Shipman Martin has developed its own specialised software for preparing Sunpath
diagrams for specific locations using standard 3D CAD models. This plots the direction and altitude of the sun
for every two minutes and every day of the year and checks whether any elements of the 3D model obstruct
the line of sight from the sun to particular reference points. It then calculates the total number of hours of
daylight during which sun obstruction will occur.
Sunpath Diagrams at test reference points are presented in Section 4 below. The Sunpath Diagrams are
projections as seen from the test reference points, and the different elements of existing and proposed
development are indicated using different coloured lines so that the relative positions of obstructions can be
readily seen. The colour coding is as follows:
Blue:
Existing buildings or structures, within or external to the site, to be retained
Cyan:
Canopies and brise soleil on existing buildings
Green:
The proposed development
Sunpath Diagrams show the full 360° panorama from each reference point, and the 180° portion of the
panorama that faces into the room and cannot receive sun is shaded in yellow. Within the unshaded part, the
intersection of the sunpath curves and the projection of the different elements of existing and proposed
development are used to calculate the current and post construction access to sunlight hours.
Daylight
The BRE Report recommends the calculation of the Vertical Sky Component. The Vertical Sky Component (VSC)
is defined as “The ratio of that part of illuminance, at a point on a given vertical plane that is received directly
from a CIE Standard Overcast Sky, to illuminance on a horizontal plane due to an unobstructed hemisphere of
this sky”.
The maximum possible VSC value for an opening in a vertical wall, and assuming no obstructions, is 40%. BRE
209 indicates that if the VSC can be maintained above 27%, then enough skylight should still reach the window
of an existing building. If the resultant VSC is both less than 27% and less than 0.8 times its former value after
the construction of the proposed development, occupants of the building will notice a reduction in skylight.
In order to calculate the VSC for a particular reference point, a Waldram Diagram is used. A Waldram Diagram
is a geometric representation of the portion of the sky vault which might be visible from a particular reference
point. Obstructions outside the window are plotted onto the diagram, and the remaining ‘clear’ area can be
calculated as a percentage of the complete ‘unobstructed’ sky vault.
Brady Shipman Martin has developed its own specialised software for preparing Waldram Diagrams using 3D
digital models of the existing and proposed environment. This projects the 3D model onto the Waldram
Diagram, and the projection is then used to calculate those parts of the sky that will be either obstructed or
not in order to calculate the Vertical Sky Component at each test reference point.
Waldram Diagrams are presented in this report for test reference points in Section 4 below. Like Sunpath
Diagrams, Waldram Diagrams are projections as seen from the test reference points, where different elements
from the existing and proposed development are indicated using different coloured lines so that the relative
positions of obstructions can be readily seen. The colour coding is as follows:
Blue:
Existing buildings or structures, within or external to the site, to be retained
Cyan:
Canopies and brise soleil on existing buildings
Green:
The proposed development
Waldram Diagrams only show the portion of the sky that can be seen from the reference point, and therefore,
the whole area of diagram is relevant for calculation purposes. The areas of obstructed and unobstructed parts
of the sky are calculated to determine the VSC.
Overshadowing
The BRE Report acknowledges the value of sunlight in external spaces in enhancing their overall appearance,
ambience and amenity. Relevant spaces noted in the report include private gardens of dwellings, amenity
spaces such as parks, playing fields and playgrounds, and also public spaces between non-domestic buildings
and in streetscapes.
The report recommends that at least half of the area of relevant spaces should receive at least two hours of
sunlight on 21st March.
In order to determine, and to quantify, the effect of overshadowing of the proposed development on the
adjoining public spaces and properties, Sunlight Exposure Plans and Shadow Plans are prepared using 3D
digital models of existing buildings and structures in and around the Point Village and of the proposed
development.
Sunlight Exposure Plans identify the areas of the ground plane that will be capable of receiving different
durations of sunlight on any given day of the year. Sunlight exposure plans are prepared from the 21st March,
and identify areas that will receive up to 1 hour of sunlight, areas that will receive 1 to 2 hours, and areas that
will receive more than 2 hours of sunlight.
Shadow Plans provide a more conventional graphic representation, however, each one only represents a
specific period of time on the 21st March. Shadow plans are prepared for 09:00am, 12:00 noon, and 03:00pm
on the 21st March.
3. RECEIVING ENVIRONMENT
Context and Location
The development site is located along the eastern side of the Point Village Square, occupying the space
between the 3Arena and the East Wall Road, and extending from North Wall Quay into Point Village Square.
Dublin Port lies immediately east of East Wall Road, and in the vicinity of the development site, comprises
marshalling and storage yards with a small number of associated administration and security buildings.
The 3Arena is located on the western side of the development site, and extends from the North Wall Quay to
Point Village Square. Its eastern façade is substantially solid, and any windows and doors serve internal back
of house circulation areas and fire escape routes.
The Point Village District Centre is located to the north of the site and forms the northern edge of Point Village
Square. The southern part of the District Centre facing Point Village Square comprises the Gibson Hotel,
commercial office space, and ground floor retail units.
Point Village Square is a public space located between the 3Arena and the Point Village District Centre. At
present, it extends from the existing Point LUAS station eastwards to East Wall Road, and the space continues
around the 3Arena on the eastern side to North Wall Quay.
The closest residential development is at Castleforbes Square on the northern side of Mayor Street Upper,
over 200m from the development site as indicated in Figure 2 below in yellow
Figure 2: Local context of proposed development, including closest residential uses, and indicating the
horizontal and vertical elements of The Exo building.
Characteristics of the Proposed Development
The proposed development comprises a number of elements, including:
The Exo Building: a linear commercial building facing east and west, to be located along the eastern side of
the former Point Depot, now the 3Arena, and along the East Wall Road. The building will be raised some 8.0m
above ground supported on three separate elliptical cores, allowing the public space to flow freely underneath
the building. The building is expressed as two distinct but connected volumes. The southern part,
approximately 2/3 of the overall building footprint, is 8 storeys high, and the northern part rises to 17 storeys.
The overall length of the proposed Exo Building is similar to that of the 3Arena, however, The Exo building will
be positioned slightly further north. This allows the creation of a small public space at the southern end that
addresses North Wall Quay and the River Liffey, and also partly extends The Exo Building into Point Village
Square at the northern end so as to create a sense of enclosure to the public space, and to be a focal point
and city marker that will be visible from along Mayor Street.
The Public Realm: reconfiguration of parts of Point Village Square to provide enclosure along the East Wall
Road side of its current configuration, and to integrate the public space under the Exo Building with the 3Arena
and the main part of Point Village Square, and to provide connectivity between the various elements. A Glass
Box restaurant/café, some 10.0m in height, in the main part of Point Village Square will be part of the public
realm and, in conjunction with The Exo Building, will create a sense of enclosure in the space.
For a full scheme description, see the Planning Report.
4. ASSESSMENT
A set out above, there are no residential dwellings in sufficient proximity to the proposed development to
warrant detailed assessment for impacts on access to daylight, sunlight or for overshadowing.
Given the location of the proposed Exo Building, Glass Box and public realm works relative to existing buildings
in the vicinity, and the function, orientation and arrangement are existing buildings, a number of reference
points have been identified for which to carry out quantified assessment using the same standards that would
be applied to the living spaces of dwellings.
The Gibson Hotel, although commercial, incorporates a range of room types and spaces that could be
considered either public spaces of private accommodation, albeit of a temporary nature. Within the Gibson
Hotel, spaces identified for assessment of Daylight and Sunlight include:
A. Ground Floor retail units of the Point Village District Centre facing Point Village Square
B. The Third Floor restaurant of the Gibson Hotel
C. The Fourth Floor guest rooms of the Gibson Hotel.
Reference Points A, B and C are clearly identified on Figures 3 and 4 below.
In relation to Overshadowing, the public space of Point Village Square is assessed.
For Reference Points A and B, Sunlight and Daylight analysis has been undertaken in two manners. The first
set of calculations take into consideration the substantial overhangs of the first floor terrace and the brise
soleil above the third floor as relevant. The second calculations omit the presence of the terrace and brise
soleil.
In the case of Reference Point C at the fourth floor guest room, there is no existing overhang to regulate or
obstruct access to light, and a single set of calculations is provided.
Assessment of access to daylight sunlight where rooms are set back under terraces and other such features is
specifically referenced in BRE 209, ‘Site Layout Planning for Daylight and Sunlight: A Guide to Good Practice’,
Second Edition 2011, by P. J. Littlefair, It is considered reasonable to measure the access to light at the outer
edge of the terrace, even for living spaces of residential properties, as the space of the terrace is for the
enjoyment of those using the adjacent internal space.
In all cases assessed, the existing trees are omitted as recommended in the guidelines.
Figure 3: Location of test reference points for Daylight, Sunlight and Overshadowing
Figure 4: Location of test reference points for Daylight and Sunlight assessment
Point A: Ground Floor retail unit, glass frontage facing Point Village Square.
Point A, as indicated in Figures 3 and 4 above, is the eastern-most ground floor retail under the Gibson Hotel
facing Point Village Square. The glass front enclosure is set back c. 3.0m from the colonnade that supports the
first floor terrace above. As such, the frontage of the retail unit as it exists at present is substantially shielded
from direct sunlight. In addition, there is a row of trees c. 5.0m outside the colonnade that creates further
shading from direct sunlight.
Photo 1: Test Reference Point A is at the glazed front of the retail units.
Taking the terrace into account, Table A1 below, and Figures A1 and A2 further below, show the existing
Daylight value, VSE Before, is 15.1% and significantly below the recommended target of 27.0%. Post
construction, this will reduce further to 9.5%, or 0.629 times the current value. Table A1 also shows the
existing Sunlight access is 407.7 hrs annually, or 28.35% of the APSH, and 289.3 hrs or 20.12% of the APSH
during the winter months. Post construction, these will reduce to 273.1 hrs annually, or 18.99% of the APSH,
and 153.5 hrs or 10.68% of the APSH during the winter months. On this basis, the annual result post
construction is slightly below the target of 25.0% of APSH, but the Winter component, before and after
construction, is well above the recommended 5% APSH.
Table A1: Vertical Sky Component and Annual Probable Sunlight Hours at Reference Point A
Reference Point A: Ground Floor retail unit, incorporating the first floor terrace overhang
Vertical Sky Component, %
Annual Probable Sunlight
Hours
VSC Before
VSC After
Ratio
15.1%
9.5%
0.629
APSH Before
APSH After
Ratio
407.7 hrs
273.1 hrs
28.35%
18.99%
289.3 hrs
153.5 hrs
20.12%
10.68%
Annual APSH = 1437.8 hrs
0.670
Winter PSH = 465.2 hrs
0.531
By omitting the terrace overhang, the results are significantly different, as shown in Table A2. It shows the
existing Daylight value, VSE Before, is 33.7% and well above the recommended target of 27.0%. Post
construction, this will reduce to 25.4%, slightly lower than the target 27%, and marginally lower than 0.8 times
the current value. Table A2 also shows the existing Sunlight access is 990.7 hrs annually, or 68.91% of the
APSH, and 342.7 hrs or 23.84% of the APSH during the winter months. Post construction, these will reduce to
764.7 hrs annually, or 53.19% of the APSH, and 181.0 hrs or 12.59% of the APSH during the winter months.
On this basis, the annual result is well above the target of 25.0% of APSH, and the Winter component is also
well above the recommended 5% APSH.
Table A2: Vertical Sky Component and Annual Probable Sunlight Hours at Reference Point A
Reference Point A: : Ground Floor retail unit, omitting the first floor terrace overhang
Vertical Sky Component, %
Annual Probable Sunlight
Hours
VSC Before
VSC After
Ratio
33.7%
25.4%
0.754
APSH Before
APSH After
Ratio
990.7 hrs
764.7 hrs
68.91%
53.19%
342.7 hrs
181.0 hrs
23.84%
12.59%
Annual APSH = 1437.8 hrs
0.772
Winter PSH = 465.2 hrs
0.528
The form and layout of the existing retail unit, set back under the terrace overhang, is such that the existing
access to daylight by residential standards is poor, and access to sunlight is just above the residential
recommendations. By considering the space outside the unit and under the overhang as being part of the
amenity of the unit, it is clear that the access to both daylight sunlight by residential standards greatly exceeds
the recommendations.
The relative impacts of the existing buildings (the 3Arena), the existing terrace overhang, and the proposed
development on both Daylight and Sunlight, can be clearly seen in Figures A1 and A2 below. The dark blue
outline indicates the existing buildings, and they obstruct a relatively small area of the sky or the sunpaths.
The cyan colour indicated the profile of the terrace overhang, and everything above that line in both the
daylight and sunlight diagrams is obstructed by the terrace. The green colour outlines the proposed
development, and although it illustrates a 17 storey development, it obstructs much less daylight or sunlight
than the existing terrace overhang.
Retail units typically make extensive use of artificial lighting as a means of presenting attractive window
displays and creating internal ambience. The level of obstruction to daylight and to sunlight caused by the
existing terrace overhang is substantially greater than any increased obstruction anticipated by virtue of this
development.
Given the retail use of the space, and the pre-existence of the overhang, it is considered that the impact of
the proposed development on daylight and sunlight will be slight, and would be appropriate in an urban
context.
Figure A1: Point A: Ground Floor retail unit. Waldram Diagram
Figure A2: Point A: Ground Floor retail unit. Sunpath Diagram
KEY to Waldram and Sunpath Diagrams above
Blue:
Cyan:
Green:
Existing buildings or structures, within or external to the site, to be retained
Canopies and brise soleil on existing buildings
The proposed development
Point B: Third Floor restaurant unit, on terrace in line with main building wall.
Point B, as indicated in Figures 3 and 4 above, is the eastern part of the third floor restaurant terrace
overlooking Point Village Square. The restaurant is enclosed by a glass wall that leads onto the seating terrace.
The Reference Point in this instance is taken on the terrace itself, at a point that is in line with the main building
wall. It is where the seating space joins the walking space along the terrace as shown in Photo 2 below. It
should be noted that the restaurant is in fact dual aspect and it also enjoys the light provided by an atrium at
the core of the building as shown in Photo 3 below.
Photo 2: Test Reference Point B is at the edge of the seating area on the terrace.
Photo 3: Interior of restaurant (terrace to the right) with additional atrium lighting on left.
Taking the brise soleil into account, and treating it as solid even though it does permit some reflected light
through, Table B1 shows the existing Daylight value, VSE Before, is 9.6% and substantially below the
recommended target of 27.0%. Post construction, this will reduce further to 6.5%, or 0.677 times the current
value. Table B1 also shows the existing Sunlight access is 277.4 hrs annually, or 19.29% of the APSH, and 235.9
hrs or 16.41% of the APSH during the winter months. Post construction, these will reduce to 202.4 hrs annually,
or 14.08% of the APSH, and 157.0 hrs or 10.92% of the APSH during the winter months. On this basis, the
annual result, before and after construction, is below the target of 25.0% of APSH, and the post construction
value is just under 0.8 times the existing value, but the Winter component, before and after construction, is
well above the recommended 5% APSH.
Note that the values do not include any additional daylight contribution arising from the atrium space, nor any
additional daylight that is reflected as diffuse light through the brise soleil system overhead.
Table B1: Vertical Sky Component and Annual Probable Sunlight Hours at Reference Point B
Reference Point B: Third Floor restaurant unit, incorporating the brise soleil overhead
Vertical Sky Component, %
Annual Probable Sunlight
Hours
VSC Before
VSC After
Ratio
9.6%
6.5%
0.677
APSH Before
APSH After
Ratio
277.4 hrs
202.4 hrs
19.29%
14.08%
235.9 hrs
157.0 hrs
16.41%
10.92%
Annual APSH = 1437.8 hrs
0.730
Winter PSH = 465.2 hrs
0.666
By omitting the brise soleil overhang, the results are significantly different, as shown in Table B2. It shows the
existing Daylight value, VSE Before, is 36.3% and well above the recommended target of 27.0%. Post
construction, this will reduce to 30.1%, which is still well above the target 27%. Table A2 also shows the existing
Sunlight access is 988.0 hrs annually, or 68.72% of the APSH, and 379.5 hrs or 26.39% of the APSH during the
winter months. Post construction, these will reduce to 849.4 hrs annually, or 59.08% of the APSH, and 267.7
hrs or 19.24% of the APSH during the winter months. On this basis, the annual and winter month results are
both well above the target values of 25.0% of APSH, and 5% APSH during the winter months.
Table B2: Vertical Sky Component and Annual Probable Sunlight Hours at Reference Point B
Reference Point B: Third Floor restaurant unit, omitting the brise soleil overhead
Vertical Sky Component, %
Annual Probable Sunlight
Hours
VSC Before
VSC After
Ratio
36.3%
30.1%
0.829
APSH Before
APSH After
Ratio
988.0 hrs
849.4 hrs
68.72%
59.08%
379.5 hrs
276.7 hrs
26.39%
19.24%
Annual APSH = 1437.8 hrs
0.860
Winter PSH = 465.2 hrs
0.729
The design and layout of the existing restaurant and terrace space, incorporating a substantial brise soleil,
clearly indicates that regulation of daylight and sunlight has been an inherent part of the design in the existing
building and appropriate to the restaurant use.
The terrace space outside the restaurant is clearly part of the amenity of the restaurant, and it is clear that the
access to both daylight and sunlight is highly regulated by inherent design, and that application of residential
standards for this use is not appropriate. This is particularly true for daylight, and it is notable that the relatively
small reduction in sunlight will occur only in the early to mid-morning period of the winter months.
The relative impacts of the existing buildings (the 3Arena), the existing terrace overhang, and the proposed
development on both Daylight and Sunlight, can be clearly seen in Figures B1 and B2 below. The dark blue
outline indicates the existing buildings, and they obstruct a very small area of the sky or the sunpaths. The
cyan colour indicated the profile of the brise soleil overhang, and everything above that line in both the
daylight and sunlight diagrams is obstructed by the brise soleil. The green colour outlines the proposed
development, and while it illustrates a 17 storey development, it obstructs much less daylight or sunlight than
the existing brise soleil overhang.
Given the restaurant use of the space, and the existence of the brise soleil that is an inherent part of the design
of space, it is considered that the impact of the proposed development on daylight and sunlight will be slight,
and would be appropriate in an urban context.
Figure B1: Point B: Third Floor restaurant terrace. Waldram Diagram
Figure B2: Point B: Third Floor restaurant terrace. Sunpath Diagram
KEY to Waldram and Sunpath Diagrams above
Blue:
Cyan:
Green:
Existing buildings or structures, within or external to the site, to be retained
Canopies and brise soleil on existing buildings
The proposed development
Point C: Fourth Floor guest room.
Point C, as indicated in Figures 3 and 4 above, is the eastern-most guest room window at the fourth floor
overlooking Point Village Square. The Reference Point in this instance is at the window plane.
Table C shows the existing Daylight value, VSE Before, is 36.6% and substantially above the recommended
target of 27.0%. Post construction, this will reduce to 30.7% but will remain substantially above the 27.0%.
Table C also shows the existing Sunlight access is 970.2 hrs annually, or 67.48% of the APSH, and 377.8 hrs or
26.28% of the APSH during the winter months. Post construction, these will reduce to 840.6 hrs annually, or
58.47% of the APSH, and 275.2 hrs or 19.14% of the APSH during the winter months. On this basis, the annual
result, before and after construction, is substantially above below the target of 25.0% of APSH, and the winter
component in both instances is also substantially above the recommended 5% APSH.
Table C: Vertical Sky Component and Annual Probable Sunlight Hours at Reference Point C
Reference Point C: Fourth Floor guest accommodation, at window.
Vertical Sky Component, %
Annual Probable Sunlight
Hours
VSC Before
VSC After
Ratio
36.6%
30.7%
0.839
APSH Before
APSH After
Ratio
970.2 hrs
840.6 hrs
67.48%
58.47%
377.8 hrs
275.2 hrs
26.28%
19.14%
Annual APSH = 1437.8 hrs
0.866
Winter PSH = 465.2 hrs
0.728
The results above, and as illustrated in Figure C1 and C2 below, clearly demonstrate that access to both
daylight and sunlight will greatly exceed standards for residential living spaces. It is considered that the impact
of the proposed development on daylight and sunlight will be negligible.
Figure C1: Point C: Fourth Floor guest room. Waldram Diagram
Figure B2: Point C: Fourth Floor guest room. Sunpath Diagram
KEY to Waldram and Sunpath Diagrams above
Blue:
Cyan:
Green:
Existing buildings or structures, within or external to the site, to be retained
Canopies and brise soleil on existing buildings
The proposed development
Overshadowing
In the case of the proposed development, and given the absence of existing residential dwellings, the relevant
space for assessment of overshadowing and sunlight exposure is the Point Village Square.
At present, Point Village Square comprises two connected parts – that to the north of the 3Arena and the
space to the east of the 3Arena that leads down to North Wall Quay.
The proposed development, including the Exo Building and public realm works, will create better definition
and sense of enclosure to the Point Village Square while retaining the two connected parts with related
characters. For the purposes of overshadowing assessment, the solar exposure on the northern and eastern
parts are treated separately as Area A and Area B indicated on Figures D1 to D6 below.
Solar Exposure on the ground on 21st March for both the Existing and Proposed situation is shown in Figure D1
below.
It is clear from Figure D1, that on the 21st March, both areas can currently receive greater than two hours of
sunshine over almost the entire of each area. Post construction, the sunlight exposure in the area immediately
in front of the northern face of the 3Arena will be reduced to between zero and two hours. This will be as a
result of the northern part of the Exo Building extending into Point Village Square and obstructing early
morning sunshine. Post construction, Area B will experience a reduction in the central portion to between 1
and 2 hours, and this will be as a result of the middle core of the Exo building coming down to ground level.
The sunlight lost in Area B will also be early morning sunlight.
Similarly, although not strictly required under BRE209, the results for 21st June and 21st December are provided
in Figures D2 and D3 respectively.
For 21st June, Figure D2 shows that the two hour threshold is effectively not breached at all, before or after
construction.
For December, Figure D3 shows that Area A currently receives from zero to one hour in the space immediately
in front of the northern façade of the 3Arena and extending approximately half of the way across Point Village
Square, while Area B receives more than two hours. Post construction, the areas receiving from zero to one
hour, and from one to two hours, will increase to include approximately 60% of Area A and 30% of Area B. It
should be noted however that the sunlight lost will all be early morning sunlight when the amenity of the area
as a public space is less relevant.
Shadow Plans are provided for 21st March, for Existing and Proposed, in Figures D4, D5 and D6 below for
09:00am, 12:00 noon, and for 3:00pm respectively. Shadows resulting from existing buildings or structures
are shown in red, while those resulting from proposed structures are shown in blue. The figures reflect the
findings of the Sunlight Exposure findings, in that the proposed development will result in additional
overshadowing on Point Village Square in the morning hours, and that from approximately 1:00pm, there will
effectively be no additional overshadowing on Point Village Square over and above existing levels of
overshadowing.
It is considered that the public space of Point Village Square, both to the north and east of the 3Arena, will
experience some overshadowing, but given the public space nature of the area and the predominantly
afternoon and evening use of the space, such impacts will be slight.
Figure D1: Sunlight Exposure on 21st March
As Existing (top)
As Proposed (bottom)
Figure D2: Sunlight Exposure on 21st June
As Existing (top)
As Proposed (bottom)
Figure D3: Sunlight Exposure on 21st December
As Existing (top)
As Proposed (bottom)
Figure D4: Shadow Plans for 21st March at 09:00am
As Existing (top)
As Proposed (bottom)
Figure D5: Shadow Plans for 21st March at 12:00 noon
As Existing (top)
As Proposed (bottom)
Figure D6: Shadow Plans for 21st March at 3:00pm
As Existing (top)
As Proposed (bottom)
5. CONCLUSION
The Proposed development is located at the eastern end of the existing North Lotts area, and as such, there
are no potentially sensitive buildings or spaces to the east of the site. Additionally, the closest residential
dwellings to the proposed development are at Castleforbes Square approximately 200m to the west and as
such, is sufficiently far away not to be of concern in relation to the proposed development.
Therefore, there are no impacts on residential dwellings at all, and the impacts that will arise will be in the
form of partial shading and obstruction of daylight on a combination of retail, hotel and commercial uses. As
can be seen from the assessment above, the inherent design characteristics of those buildings is to
substantially shade sunlight and filter daylight to suit their designed uses. By virtue of the relative location of
the proposed building and its orientation, any such impacts will be restricted to the morning time only, and all
afternoon and evening shadows arising from the development will fall east of any existing built development.
Point Village Square, the public space at Point Village, will experience some additional overshadowing, but the
residual access to sunlight will be greater than the recommendations set out in BRE209. The lossof sunlight
will be limited to the morning hours only when the public spaces are less used.
It should also be noted that the overall development proposals are designed to enhance the public realm by
creating a greater sense of enclosure, together with animated frontage, revised pedestrian permeability and
new elements of visual interest – all of these factors will contribute to the quality and amenity of the public
space and it is considered that any increase in overshadowing will be more than compensated for by the other
benefits accruing to the public space and its amenity value.
The impacts on Daylight, Sunlight and Overshadowing are slight to none, and are considered appropriate in an
urban context.