This document provides lighting calculations and proposals for two spaces in a community library: 1) A multifunctional space on the first floor that could be used for exhibitions or workshops. Daylight factor calculations found this space would be too bright. Artificial lighting of 23 recessed LED luminaires arranged in a 6x4 layout is proposed to provide 400 lux. 2) A general reading area on the second floor. Artificial lighting of 29 recessed LED luminaires arranged in a 5x6 layout is calculated to provide the required 300 lux. Both spaces will utilize a PSALI scheme to control circuits and reduce energy consumption while maintaining illuminance.

1. School of Architecture, Building and Design
Bachelor of Science (Hons) in Architecture
Building Science II
Project 2: Integration Project
Jalan Tuanku Abdul Rahman
Community Library
Name: Janice Lee Juen Yung
Student ID No.: 0318695
Tutor: Ar Edwin Chan

2. Table of Content
1.0Lighting Calculation for Multifunctional Space
1.1Daylight Factor Analysis
1.2Artificial Lighting Proposal
1.3PSALI Scheme
1.4 Effective Methods of Maintaining Visual and Thermal Comfort
2.0Lighting Calculation for Indoor & Outdoor General Reading Area
2.1Artificial Lighting Proposal
2.2PSALI Scheme

3. 1.0 Lighting Calculation for Multifunctional Space on First Floor
1.1Daylight Factor Analysis
The multifunctional space which is located on the first floor towards the front facade
of the community library is a space where it can be transformed to exhibition and
indoor workshop area. The room height of this space is 3 meters.

4. Based on MS1525, the daylighting factor distributions are stated as on the table
below:
Zone Daylight Factor (%) Distribution
Very Bright >6 Too bright with thermal and glare
problems
Bright 3 – 6 Good
Average 1 – 3 Fair
Dark 0 – 1 Poor
Daylight Factor Calculation
Area of window exposed to sunlight (m2) 8.8 x 2 = 17.6
Total Internal Surface Area 2(9.25 x 2) + 2(6.6 x 3) + 2(9.25 x 6.6) = 95.1
Average Daylight Factor
W/A x [T∂/(1-R)]
17.6 / 95.1 x [0.6 x 65/(1 – 0.45)]
= 0.08 x 82.91
= 6.72%
Note: Assuming all walls except for the one facing the façade is solid wall
painted in grey paint finish. Transmittance value for window is 0.6, Sky angle
in 76°, and average reflectance value of 0.45.

5. Natural Illumination Calculation
Illuminance (lux) Example
120 000 Very bright sunlight
110 000 Bright sunlight
20 000 Clear sky
1000 – 2000 Overcast sky
400 Sunrise / Sunset
< 200 Midday
40 Fully overcast
< 1 Sunset, Storm
External = 20 000 lux ( Clear Sky)
DF = E_internal / E_external x 100%
6.71 = (Ei / 20 000) x 100%
= 1,342 lux
Based on the requirements set by MS1525, the space is very bright with thermal and
glare problems.

6. 1.2Artificial Lighting Proposal
Based on MS 1525, the required lux level for a workshop or a similarly functioning
space is 400 lux.
Lumen Method Calculation
Proposed Luminaire
Type of fixture Recessed LED Luminaire
Type of model BBS560 (600mm x 600mm module)
Company Philips
Luminous Flux (lm) 3100 lm
Power (W) 26 W
Color Designation White
Lumen Maintenance Factor 0.8
Dimension of Room 6.6 x 9.25
Floor Area (A) 61.05
Height of ceiling (m) 3.0
Height of work level (m) 0.8
Mounting Height (Hm) 2.2
Reflection Factor White Plaster Ceiling = 0.7
Wood Panel Wall = 0.5
Laminated Woodblock Floor = 0.2
Room Index (K) K = 6.6 x 9.25 / 2.2 x (6.6 + 9.25)
= 61.05 / 34.87
= 1.75
Utilisation Factor (UF) 0.44
Maintenance Factor (MF) 0.8
Number of Lamps Required N = 400 x 61.05 / (3100 x 0.44 x 0.8)

7. = 24420 / 1091.2
= 22.38 ~ 23 lamps
Spacing to Height Ratio (SHR) SHR = 1/Hm x √(A/N)
= 1 / 2.2 x √(61.05 / 23)
=0.45 x 1.63
= 0.74
SHR = S / 2.2 = 0.74
S = 1.63
Fittings Layout Fittings required = 9.25 / 1.61 = 5.67 ~ 6 rows
Fittings required = 6.6 / 1.61 = 4.05 ~ 4 rows
Space along Wall = 9.25 / 6 = 1.54 m
Space along Wall = 6.6 / 4 = 1.65 m
Fitting Layout
The indoor workshop is arranged with 6 by 4 rows of recessed LED luminaires to
achieve the MS 1525 requirement of a minimum 400 lux. This sufficient illuminance
will allow work to be done efficiently and properly.

8. 1.3PSALI Scheme
Based on the calculations and light contour analysis, the luminaires are split into 3
circuits. On a bright day, the green circuit can be switched on to light up the
multifunctional space. However, on a slightly gloomy day, the red circuit can be

9. switched on to brighten the room. All circuits including the blue circuit is switched on
on a late evening or night. The total illuminance of the room is remained constant
with very slight changes only as the luminaires are segregated into 3 different
circuits. By doing so, not only did the total illuminance of the room has very slight
changes only, it also reduces the energy consumption of the building.
1.4 Effective Methods of Maintaining Visual and Thermal Comfort
During the day, natural daylight that penetrates through the space may cause
thermal and glare problems. In order to tackle thermal and glare problems, motorised
roller blinds will be placed along the windows of the room and can be controlled
when the thermal and visual comfort decreases.

10. 2.0 Lighting Calculation for General Reading Area
2.1Artificial Lighting Proposal
Because of the nature of activities that will be held in the general reading area
located on the 2nd floor of the community library, it is crucial that the space is well lit
at all times of the day especially during the evening as activities will be going on,
hence, artificial lighting is still needed. Based on MS 1525, the required lux level for a
workshop or a similarly functioning space is 300 lux.

11. Lumen Method Calculation
Proposed Luminaire
Type of fixture Recessed Mini Luxspace
Type of model DN560B
Company Philips
Luminous Flux (lm) 1000
Color Designation Warm White
Lumen Maintenance Factor 0.8
Dimension of Room 5.4 x 7.6
Floor Area (A) 41 m2
Height of ceiling (m) 3.0
Height of work level (m) 0.5
Mounting Height (Hm) 2.5
Reflection Factor White Plaster Ceiling = 0.7
Wall = 0.5
Floor = 0.2
Room Index (K) K = 5.4 x 7.6 / 2.5 x (5.4 + 7.6)
= 41 / 32.5
= 1.26
Utilisation Factor (UF) 0.54
Maintenance Factor (MF) 0.8
Number of Lamps Required N = 300 x 41 / (1000 x 0.54 x 0.8)
= 12300 / 432
= 28.47 ~ 29 lamps

12. Spacing to Height Ratio (SHR) SHR = 1/Hm x √(A/N)
= 1 / 2.5 x √(41 / 29)
=0.4 x 1.19
= 0.48
SHR = S / 2.5 = 0.48
S = 1.2
Fittings Layout Fittings required = 7.6 / 1.2 =6.3 ~ 6 rows
Fittings required = 5.4 / 1.2 = 4.5 ~ 5 rows
Space along Wall = 7.6 / 6 = 1.27 m
Space along Wall = 5.4 / 5 = 1.08 m
Fitting Layout
The general reading area is arranged with 5 by 6 rows of recessed LED luminaires to
achieve the MS 1525 requirement of a minimum 300 lux. This sufficient illuminance
will allow work to be done efficiently and properly.

13. PSALI Scheme

14. Based on the calculations and light contour analysis, the luminaires are split into 3
circuits. On a bright day, the green circuit can be switched on to light up the general
reading area. However, on a slightly gloomy day, the red circuit can be switched on
to brighten the room. All circuits including the blue circuit is switched on, on a late
evening or night. The total illuminance of the room is remained constant with very
slight changes only as the luminaires are segregated into 3 different circuits. By
doing so, not only did the total illuminance of the room has very slight changes only,
it also reduces the energy consumption of the building.