building science ii: lighting integration report

BUILDING SCIENCE IIBLD 61303 / ARC 3413

PROJECT INTEGRATION: LIGHTING ANALYSIS

CHEN EE DONG0321181

TUTOR: MR SIVA

TABLE OF CONTENTS1

CHEN EE DONG0321181

1.0 INTRODUCTION

2.0 SPACE 1: MAIN READING ZONE2.1 Natural Daylighting

Daylight FactorNatural Illuminance

2.2 Artificial LightingLumen Method

2.3 PSALI

3.0 SPACE 2: TEA LOUNGE3.1 Natural Daylighting

Daylight FactorNatural Illuminance

3.2 Artificial Lighting Lumen Method

3.3 PSALI

1.0 INTRODUCTION

2CHEN EE DONG0321181

This project is an integrated module with the Design Studio V project, which is a community library, focusing on principles of lighting in both natural and artificial lighting strategies.

The site in which the community library is located in is Jalan Petaling, Kuala Lumpur. The said community library is orientated in an east-west direction; hence, east and west facades of the library are most prone to direct sunlight. Some issues might arise due to the excess of sunlight, and some key spaces might experience issues in which there is not sufficient illumination. Through this project, natural daylighting strategies shall be explored and artificial lighting shall be proposed where appropriate, alongside PSALI scheme to optimize daylighting in spaces without forgoing illumination quality.

2.0 SPACE A: MAIN READING ZONEThe main reading zone is located at the rear of the building on the first floor. It is open to the public and not too user specific, catered for library activities


such as reading and writing. Hence, sufficient task lighting has to be installed with appropriate spacing to provide an adequate level of illumination to the room in order to provide an enjoyable library experience for the patrons.

Figure 2.0: First floor plan denoting main reading zone and area dimensions.

2.1 NATURAL DAYLIGHTINGNatural daylighting is a passive method of introducing light into space to provide adequate and comfortable levels of illumination.


Daylight factorDaylight factor is usually used to determine the ratio of internal illuminance level to external illuminance level and is defined using the formula

DF = totalareaof openingstotal floor area×100%

Daylight factor is then compared with standard MS 1525 requirements to determine the lighting conditions of the space.

Daylight Factor CalculationsDaylight factor formula DF = totalareaof openingstotal floor area

×100%

Total floor area of space (m2) 11.4 m × 7.191 m = 81.977 m2

Total area of window openings exposed to sun (m2)

Window opening per unit = 5.845 m2

5.845 m2 × 2= 11.684 m2

Daylight factor, DF (%) 11.68481.977

×100%

= 0.1425 × 100 %= 14.25 × 0.1= 1.425 %

Zone Daylight Factor/%

Distribution

Very bright >6 Very large with thermal and glare problems.

Bright 3-6 GoodAverage 1-3 FairDark 0-1 Poor

Figure 2.1.a: Daylight Factor according to MS 1525 table.

ConclusionAccording to the MS 1525 requirements, the daylight factor of the main reading room is fairly illuminated. The lighting conditions are considered


average. This might be due to the lack of fenestration in the eastern façade (only 2 2m wide windows), which are highly efficient in introducing daylight during the morning (eastern sun). However, as the sun gravitates west, the main reading area may experience darkness which would deter reading activities in the zone due to eye strain from the lack of illumination.

Natural Illumination CalculationsLuminance level/lux) Luminance example120000 Brightest sunlight110000 Bright sunlight20000 Shade illuminated by clear blue sky;

midday1000-2000 Typical overcast day; midday400 Sunrise/sunset on a clear day (ambient)< 200 Extreme or darkest storm clouds; midday40 Fully overcast, sunset/sunrise< 1 Extreme of darkest storm clouds,

sunset/sunriseFigure 2.1.b: Luminance intensity according to MS 1525 standard.

Formula DF = E internal (Ei )Eexternal (Eo)× 100%

E external, Eo (lux), given from Figure X

20000 lux

Daylight factor, DF (%) 1.425 %Natural illumination of Space A 1.425 = Einternal (Ei)

20000×100%

Ei = 285 lux

ConclusionThe standard illumination level required for a reading space is 300 lux (library minimum). Natural illumination of the main reading zone is 285 lux which is close to the standard illumination level, hence, 15 lux more is required. This can be easily achieved by introducing some form of artificial lighting into the space to light up the areas which cannot be reached by natural daylight during the day.


Renderings and Light Contour

Figure 2.1.c: Daylight contour at 9 am.

Figure 2.1.d: Daylight contour at 12 pm.


Figure 2.1.e: Daylight contour at 3 pm.

2.2 ARTIFICIAL LIGHTINGAs the library has a proposed 24/7 scheme, indicating that public areas like the main reading zone will be opened throughout the night too, the space cannot be fully dependent on solely natural daylighting strategies. Artificial lighting is to be incorporated into the spaces to provide a well-illuminated, comfortable and relaxing working area especially when natural light levels are low.

Lumen method Philips Luxspace DN570B LED20S Type of fixture Recessed

downlightType of bulb LED


Source: Philips lighting product catalogue

Power 36 WVoltage 240 VLuminous flux 3000 lmLifetime of luminaire

70000 hours

Luminaire colour

Warm white

Colour temperature (K)

4000 K

Colour rendering index (CRI)

100

Figure 2.2.a: Type of luminaire

Space dimensions, L × W (m) 11.4 m × 7.191 m

Total floor area (m2) 81.977 m2

Types of luminaire Philips LED recessed downlightLumen of luminaire, F (lm) 2200 lmHeight of luminaire (m) 3.5 mHeight of working plane (m) 0.8mMounting height, Hm (m) 2.7 mReflection factors (%) Ceiling: 0.7

Wall: 0.5Floor: 0.2

Room index, K

RI = L×WHm×(L+W )

11.4×7.1912.7×(11.4+7.191)

= 1.633

Utilization factor, UF (refer to table)

0.6

Maintenance factor, MF 0.8Standard illuminance, E (lux) 300Number of lighting fixtures, N = E× AF ×UF×MF

300×(81.977)3000×0.6×0.8

= 24593.1/1440= 17.07 = 18 fixtures


Spacing to height ratio (SHR)

( 1Hm )×√ ANSHR = ( 1Hm )×√ AN = ( 12.7 )×√ 81.97718 = 0.79046

Smax = SHR x Hm= 0.79046 × 2.7= 2.134 m

Luminaire fitting layout Number of fittings across 11.4 m wall= 11.42.134= 5.34= 6 rows

Number of fittings in each row = 186= 3 fittings per row

Spacing along 7.191 m wall= 7.1913= 2.397 m

Luminaire fitting layout


Figure 2.2.b: Luminaire spacing layout for main reading zone according to calculated dimensions and spacing.

Figure 2.2.c: Section of the main reading zone with artificial lighting (recessed downlight).

ConclusionArtificial lighting is installed in a layout of 6 rows of 3 luminaires each to ensure an even distribution of light in the main reading zone. The luminaires are arranged in a grid of 2.134 m x 2.397 m.Light contour with artificial lighting


Figure 2.2d: Light contour at 3pm (sun away from façade) with artificial lighting.

2.3 PSALI (Permanent Supplementary Artificial Lighting of Interiors)

Figure 2.3.a: Reflected ceiling plan of the main reading zone.

Based on the number of luminaires required and the calculated spacing dimensions, the 18 luminaires can be controlled using 2 switches. Switch A will control the first 6 luminaires closest to the window openings, while Switch B will control the other 2 rows of luminaires (12 units). The PSALI strategy is arranged in such a way that during daytime, the two rows of luminaires located deeper into the building will be switched on while Switch A is turned off. This is because the illumination provided by the row of luminaires at the front is replaced by natural daylighting from the window openings, making the PSALI scheme cost effective as electricity can be


saved. During the night where there is no daylight element, Switch A and Switch B (all luminaires) is turned on to illuminate the space.

Figure 2.3.b: (left) Row of luminaires closest to the facade) is not switched on during

daytime, but row of luminaries deeper into the building is switched on; (right) every row of luminaries are switched on during the night.

3.0 SPACE B: TEA LOUNGE


The tea lounge is located at the front of the first floor. Hence, it would receive maximum sunlight during the evening sun (west). The tea lounge is catered for leisure reading activities and function as a break-out area for patrons, providing them a space to mingle accompanied with light refreshments.

Figure 3.0: First floor plan denoting Space B and area dimensions.

3.1 NATURAL DAYLIGHTING14

CHEN EE DONG0321181

Daylight Factor CalculationsDaylight factor formula DF = totalareaof openingstotal floor area

×100%

Total floor area of space (m2) 10.0 m × 4.308 m= 43.08 m2

Total area of window openings exposed to sun (m2)

Window opening per unit = 4.650 m2

4.650 m2 × 4= 18.6 m2

Daylight factor, DF (%) 18.643.08

×100%

= 0.432 × 100 %= 43.20× 0.1= 4.32 %

Zone Daylight Factor/% DistributionVery bright >6 Very large with thermal and glare

problems.Bright 3-6 GoodAverage 1-3 FairDark 0-1 Poor

Figure 3.1.a: Daylight Factor according to MS 1525 table.

ConclusionThe daylight factor of the tea lounge is 4.32 %, which indicates that the lighting condition of the space is good as the space is brightly and adequately lit. The pivoting doors allow a large influx of daylight into the building, which justifies the brightness of the space. Hence, this can be a well-illuminated space for library patrons to do leisure reading and enjoy light refreshments.

Natural Illumination Calculations


Luminance level/lux) Luminance example120000 Brightest sunlight110000 Bright sunlight20000 Shade illuminated by clear blue sky;

midday1000-2000 Typical overcast day; midday400 Sunrise/sunset on a clear day (ambient)< 200 Extreme or darkest storm clouds; midday40 Fully overcast, sunset/sunrise< 1 Extreme of darkest storm clouds,

sunset/sunriseFigure 3.1.b: Luminance intensity according to MS 1525 standard.

Formula DF = E internal (Ei )Eexternal (Eo)× 100%

E external, Eo (lux), given from Figure X

20000 lux

Daylight factor, DF (%) 4.32 %Natural illumination of Space B 4.32 = Einternal (Ei)

20000×100%

Ei = 864 lux

ConclusionThe standard illumination level required for a lounge is 150 lux. The natural illumination of the space however is 864 lux, exceeding the standard requirements by 715 lux. The space is amply illuminated but might have glare problems or thermal discomfort. Appropriate shading devices are recommended to reduce such problems and provide optimum user comfort.


Renderings and Light Contour

Figure 3.1.c: Daylight contour at 9 am.

Figure 3.1.d: Daylight contour at 12 pm.

Figure 3.1.e: Daylight contour at 3 pm.


3.2 ARTIFICIAL LIGHTINGAs the library has a proposed 24/7 scheme, indicating that public areas like the tea lounge will be opened throughout the evening and night too, the space cannot be fully dependent on solely natural daylighting strategies. Artificial lighting is to be incorporated into the spaces to provide a well-illuminated, comfortable and relaxing working area especially when natural light levels are low.

Lumen method Philips UnicOne Compact

Pendant LEDType of fixture Pendant

Source: Philips lighting product catalogue

Type of bulb LED Power 31 WVoltage 240 VLuminous flux 2400 lmLifetime of luminaire

70000 hours

Luminaire colour

Warm white

Colour temperature (K)

3000 K

Colour rendering index (CRI)

100

Figure 3.2.a: Type of luminaire proposed

Space dimensions, L × W (m) 10.0 m × 4.308 m

Total floor area (m2) 43.08 m2

Types of luminaire UnicOne Compact Pendant LEDLumen of luminaire, F (lm) 2400 lmHeight of luminaire (m) 3.0 mHeight of working plane (m) 0.8mMounting height, Hm (m) 2.2 mReflection factors (%) Ceiling: 0.7

Wall: 0.5Floor: 0.2


Room index, K

RI = L×WHm×(L+W )

10.0×4.3082.2×(10.0+4.308)

= 1.37

Utilization factor, UF (refer to table)

0.6

Maintenance factor, MF 0.8Standard illuminance, E (lux) 150 luxNumber of lighting fixtures, N = E× AF ×UF×MF

150×43.082400×0.6×0.8

= 6462/1152= 5.609= 6 fixtures

Spacing to height ratio (SHR)

( 1Hm )×√ ANSHR = ( 1Hm )×√ AN = ( 12.2 )×√ 43.086 = 1.218

Smax = SHR x Hm= 1.218 × 2.2= 2.68

Luminaire fitting layout Number of fittings across 10.0 m wall= 10.02.68= 3.731= 4 rows

Number of fittings in each row = 64= 1.5 = 2 fittings per row

Spacing along 4.308 m wall= 4.3082= 2.154 m


Luminaire Fitting Layout

Figure 3.2.b: Luminaire fitting layout in the tea lounge according to calculated dimensions and spacing.

Figure 3.2.c: Section of the tea lounge with artificial lighting (pendant downlight).

CONCLUSION


Artificial lighting in the tea lounge is organized in a layout of 4 rows of 2 luminaires each to fulfil standard illumination requirements and provide a well-roundded illumination throuhgout the room, especially during night time when the daylight element is not applicable.LIGHT CONTOUR WITH ARTIFICIAL LIGHTING

Figure 3.2d: Light contour at 9 am (sun furthest away from façade)

3.3 PSALI (Permanent Supplementary Artificial Lighting Interiors)

Figure 3.3.a: Reflected ceiling plan of the tea lounge.


Based on the calculated number of luminaires and the spacing layout, the total of 8 luminares can be controlled using 2 light switches. The first 4 luminaires facing the front can be controlled using Switch A and the 4 luminaires at the back can be controlled using Switch B. Hence, the rows of luminaires can be controlled differently according to the level of illumination required for the room. As the daylight factor of the tea lounge is 4.32 %, indicating that the space is well-lit during the day, the Switch A can be turned off as natural daylight is able to illuminate the front of the room but not the back, hence, luminaires controlled by Switch B has to be switched on.

Figure 3.3.b: (left) Row of luminaires closests to the balcony (outdoors) is not switched on during daytime, but row of luminaries deeper into the building is switched on; (right) every

row of luminaries are switched on during the night.

This alternating strategy of PSALI application can enable a lowered cost of electricity as not all lights have to be switched on by optimizing the benefits of natural daylight illumination.
