Chapter 8 perception on indoor environmental conditions

Chapter 8: Perception of Indoor Environmental Conditions
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CHAPTER 8: PERCEPTION OF INDOOR ENVIRONMENTAL
CONDITIONS
8.0 Introduction
Building occupants view the indoor environment in a holistic way. The mechanisms
involved in human observation and perception of this holistic environment are complex.
Sensory stimulation is a starting point which has been previously researched both in a
medical context and subsequently from the point of view of the design and assessment of the
built environment (Williams, 1997). However, individual responses to the various levels of
different environmental factors such as temperature, light and sound are also understood to
be affected by non-physiological factors. These psychological effects are the subject of a
similar field of study concerning the human brain’s interpretation of environmental and
personal motivation. This interpretation has previously been addressed using simple
assessment in which the occupants perceive the relative merits of various environmental
aspects.
Judgements concerning the environment may take the form of an expression of sensation,
how good the condition of an aspect is, or a judgement of satisfaction or dissatisfaction with
individual environmental aspects or the whole. In addition the importance the occupant
attaches to the aspect, and the perceived level of personal control over it, may be used to set
other responses into context. The collation of this type of subjective, detailed information, in
conjunction with quantifiable measurement of the environmental aspects concerned, is
necessary if the natural holistic response to the environment is to be addressed.
This chapter describes how users perceive the environment in their building. The data
discussed in this chapter is derived from the questionnaires obtained from users in the case
study buildings. The objective of this chapter is to evaluate the perception of the respondents
of environmental conditions in bioclimatic building and compare with those in conventional
buildings. The aim is to find out whether or not users in bioclimatic buildings, particularly in
office areas, have better indoor environmental conditions than those in conventional ones. In
addition, communal spaces were also evaluated as parts of the study to determine the
significant impact of these areas to the main office areas. The evaluated environmental
features are listed in table 8. 1 and the rating scales used for the evaluation are shown in table
8.2 to 8.4.

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Table 8.1: Indoor environment evaluation diagram
A. Office Spaces B. Communal Spaces
Thermal Thermal
Thermal sensation in the office Quality of thermal at Lift Lobby
Quality of thermal condition in the office Quality of thermal at Corridor
Satisfaction towards thermal condition
Ventilation Ventilation
Air Movement from natural ventilation Quality of natural ventilation at lift lobby
Quality of natural ventilation Quality of natural ventilation at corridor
Satisfaction towards natural ventilation Quality of air conditioner at lift lobby
Air circulation from air conditioner Quality of air conditioner at corridor
Quality of air conditioner air circulation
Satisfaction towards air conditioner
Lighting Lighting
Level of natural light in the office Quality of natural light at lift lobby
Quality of natural light in the office Quality of natural light at corridor
Satisfaction level towards natural light Quality of artificial lighting at lift lobby
Level of artificial lighting Quality of artificial lighting at corridor
Quality of artificial lighting
Satisfaction towards artificial lighting
Acoustic Acoustic
Noise condition in the office Quality of noise at lift lobby
Quality of the noise Quality of noise at corridor
Satisfaction towards noise condition
Table 8.2: Rating scales used for environmental satisfaction
Description of evaluation elements
negative neutral positive
-3 -2 -1 0 1 2 3
Thermal
Satisfaction Towards the Overall Thermal Condition in
Office
Highlysatisfied
Verysatisfied
Satisfied
Neutral
Dissatisfied
Verydissatisfied
Highlydissatisfied
Natural Ventilation
Overall Satisfaction with the Natural Ventilation
Available in Office
Air Conditioner Circulation
Overall Satisfaction Towards Air Conditioner Air
Movement in Office
Natural Lighting
Overall Satisfaction With the Natural Light Available
in the Office
Artificial Lighting
Overall Satisfaction With the Artificial Lighting
Available in Office
Noise
Satisfaction of the Overall Noise Level in Office

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Table 8.3: Rating scales used for environmental condition
Description of evaluation
elements
negative neutral positive
-3 -2 -1 0 1 2 3
Thermal
Overall Thermal Condition
in Office is Considered
Hot
Too
Warm
Slightly
warm
Comfortable
Slightly
cool
Cool
Very
cold
Natural Ventilation
Overall Air Movement from
Natural Ventilation in Office
Much
too
breezy
Too
breezy
Slightly
breezy
Just right
Slightly
still
Too still
Much
too still
Air Conditioner
Circulation
Overall Air Movement from
Air Conditioner in Office
Much
too
breezy
Too
breezy
Slightly
breezy
Just right
Slightly
still
Too still
Much
too still
Natural Lighting
Overall Level of Natural
Light at Working Station
Much
too dim
Too dim
Slightly
dim
Just nice and
clear
Slightly
bright
Too
bright
Much
too
bright
Artificial Lighting
Overall Level of Artificial
Lighting Available At
Working Station
Much
too dim
Too dim
Slightly
dim
Just nice and
clear
Slightly
bright
Too
bright
Much
too
bright
Noise
Overall Noise Level in
Office
Much
too quiet
Too
quiet
Slightly
quiet
Just nice
Slightly
noisy
Too
noisy
Much
too noisy
Table 8.4: Rating scales used for environmental quality
Description of evaluation elements negative neutral positive
-2 -1 0 1 2
Thermal Quality:
Poor
Fair
Adequate
Good
Excellent
Temperature Level at Working Station
Temperature Level at Lift Lobby
Temperature Level at Meeting Area
Temperature Level at Corridor
Natural Ventilation Quality:
Natural Ventilation Available at Work Station
Natural Ventilation Available at Lift Lobby
Natural Ventilation Available at Meeting Area
Natural Ventilation Available at Corridor
Air Conditioner Circulation Quality:
Air Conditioner Circulation at Working Station
Air Conditioner Circulation at Lift Lobby
Air Conditioner Circulation at Meeting Area
Air Conditioner Circulation at Corridor
Natural Lighting Quality:
Natural Light Available at Working Station
Natural Light Available at Lift Lobby
Natural Light Available at Meeting Area
Natural Light Available at Corridor
Artificial Lighting Quality:
Artificial Lighting Available at Working Station
Artificial Lighting Available at Lift Lobby
Artificial Lighting Available at Meeting Area
Artificial Lighting Available at Corridor
Noise Quality:
Noise Level at Working Station
Noise Level at Lift Car/Lobby
Noise Level at Meeting Area
Noise Level at Corridor

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8.1 Thermal Resistance Value of Clothing (clo value)
Clo value is a numerical representation of a clothing ensemble's thermal resistance, 1 Clo =
0.155 m2
K/w. The thermal resistance value of clothing (clo value) for all respondents was
calculated using a clo calculator in ASHRAE thermal comfort program. The clo calculator is
a tool used to generate and store personal own clothing ensembles. Part of the clo calculator
window is shown below. The clo value for an individual respondent in the survey was
calculated by clicking on the items available in the window based on his/her clothing
interpretation in the questionnaires as shown in figure 8.2. The clo value is automatically
calculated during the clothing ensemble process. The total clo value for every individual in
each building was later recorded in the MS Excel for analysis.
Figure 8.1: Clo calculator template in ASHRAE thermal comfort program.
The clo value for all respondents ranged from 0.54 to 1.14 with an average of 0.68. The
analysis results show that women respondents have a wider range of clo values than men.
Men and women respondents’ respective clo value ranged from 0.57 to 1.06 and 0.54 to
1.14. The average maximum for both bioclimatic and conventional buildings is 1.06 and 0.97

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respectively whereas the average minimum clo value for both types of building is 0.54. The
average clo value for both types of buildings differs by 0.01: 0.67 in bioclimatic and 0.68 in
conventional building.
Table 8.5: Thermal resistance value of clothing (clo value) for all buildings
Clothing
(clo) Value
UMNO MNIAGA IBM Average KOMTAR TIMA LUTH Average
Average 0.68 0.71 0.62 0.67 0.65 0.73 0.66 0.68
Std Div 0.13 0.15 0.12 0.13 0.09 0.16 0.09 0.12
Min 0.55 0.54 0.54 0.54 0.54 0.54 0.54 0.54
Max 0.99 1.14 1.06 1.06 0.93 1.06 0.93 0.97
The level of occupants’ activity in the office spaces varies from reading, sitting, writing,
typing, filing and walking about. Therefore the metabolic rate varies from 1.0 met to 1.7 met
with a mean average metabolic rate of 1.35 met (ASHRAE, 1993). Thermal resistance value
of clothing for all buildings is shown in table 8.4.
Discussion:
Thermal sensation depends on skin temperature and the heat exchange with the environment
depends on the ambient climatic conditions (air and radiant temperature, vapour pressure,
and air speed) but is also modified by the thermo physical properties of the clothing
(specifically its insulation (clo) and vapour transfer (im) values (Givoni & Goldman, 1972).
The addition of thermal resistance due to clothing affects heat transfer mechanisms between
the human body and the environment (dry heat exchange). Dry heat exchange represents the
heat exchange between the human body and the environment through convection and
radiation heat transfer. The actual insulation value (clo) decreases and the evaporative
permeability coefficient (im) of the clothing increases.

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8.2 Thermal Condition
This section presents user’s perceptions of the indoor thermal conditions and their
satisfaction level with them. Perceptions were deliberated using several rating scales in the
survey that evaluated thermal conditions mainly in the office areas and communal spaces in
the building. Overall condition and satisfaction towards thermal condition were also rated in
this section.
Thermal Sensation
The distribution of the thermal sensation ratings in all buildings and in total is shown in table
8.6 and the histogram and normal curve for both types of building is shown in figure 8.2.
The statistics indicate that respondents in bioclimatic buildings are more thermally
comfortable than those in non bioclimatic buildings. The highest rated is MESINIAGA
where almost 80% feel comfortable whereas TIMA is the lowest rated building where less
than 30% feel comfortable and about 15% feel very cold (see table 8.6). LUTH is the highest
rated among conventional types and UMNO is the lowest rated for bioclimatic type. The
rating also indicates that more than 25% (1/4) of the respondents in UMNO, IBM and TIMA
feel cold whereas about 25% (1/4) in KOMTAR feel warm to hot and 10% in UMNO feel
warm.
Satisfaction towards the Thermal Condition in Building
Significantly, more than 25% (1/4) of the respondents in KOMTAR are dissatisfied with the
thermal condition (about the same ratio that feels warm and hot) as shown in table 8.7. 15%
of respondents in UMNO feel dissatisfied (the same ratio that feels warm). However those
who feel cold in IBM and TIMA seem to feel satisfied with the condition as 5% or less feel
dissatisfied in those buildings. Despite that, more than 50% respondents in MESINIAGA,
IBM, TIMA and LUTH are satisfied. These show that MESINIAGA is the highest rated
building among all, where almost 80% are satisfied and KOMTAR is the lowest rated (see
table 8.7).
Discussion:
The average air temperature measured in TIMA (22.8°C) was found to be the lowest among
the others (see chapter 7: table 7.1) and significantly more than 65% of respondents in TIMA
feel slightly cool to very cold. MESINIAGA and KOMTAR respectively have the same
average air temperature which is 24.6°C (the highest among all). However the users
perceived differently in these buildings; 40% of the respondents in KOMTAR feel slightly

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warm to hot whereas only 12% respondents in MESINIAGA feel slightly warm. With the
same average temperature, users in MESINIAGA are likely to feel more comfortable than in
KOMTAR where 79.2% rated it comfortable in MESINIAGA and only 46.3% in KOMTAR.
When asked about their level of satisfaction towards the thermal condition in the building,
about 75% (2/3) of the respondents in each building rated between neutral and highly
satisfied (see table 8.7). As discussed earlier (see chapter 7), TIMA has the lowest average
air temperature (22.8°C) and more than 65% of it respondents feeling slightly cool to very
cold. Surprisingly 60% of the respondents are satisfied with the overall thermal condition in
the building. KOMTAR with the highest average air temperature 24.6°C has 40% of
respondents feeling slightly warm to hot, showing a significant result as 26.8% (1/4) of the
respondents are dissatisfied with the overall thermal conditions. However in MESINIAGA,
with the same average air temperature almost 80% of the respondents are shown to be
satisfied, whereas in UMNO the respondents are more neutral and slightly satisfied.
Collectively, most of the respondents in both types of building are satisfied with the
condition with highest rating of 51.6% for bioclimatic buildings and 49.0% for conventional
ones (see figure 8.3). Although the figures in both types show little difference, the overall
distribution in both types varies from ‘highly satisfied’ to ‘dissatisfied’ for bioclimatic
buildings and ‘very satisfied’ to ‘highly dissatisfied’ for conventional types. This voting
pattern clearly give an indication that users in bioclimatic buildings are relatively more
satisfied than those in conventional buildings in terms of thermal comfort condition and
satisfaction. However the chi-square value and asymptotic significance 2-sided for the cross
tabulation is (χ2
= 9.62, p = 0.087), which means it is statistically not significant (p > 0.05)
and it happens by chance (see figure 8.3).
Table 8.8 – 8.10 present the perception statistic of subjects towards thermal conditions in
several areas in their building and figure 8.4 shows the histogram and normal curve. The
pattern indicates that the thermal condition in bioclimatic buildings in office spaces (users’
workstation) and communal areas (lift lobby and corridor), are highly rated by the
respondents in those buildings as compared to the rating obtained in non bioclimatic
building.

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Table 8.6: Rating frequency for overall thermal sensation in the office
BUILDING UMNO MNIAGA IBM KOMTAR TIMA LUTH TOTAL
hot 17.1% 8.3% 5.6%
too warm 12.2% 3.0% 8.3% 5.0%
slightly warm 11.1% 12.5% 12.2% 3.0% 8.3% 8.1%
comfortable 50.0% 79.2% 60.0% 46.3% 27.3% 58.3% 51.3%
slightly cool 22.2% 35.0% 4.9% 45.5% 4.2% 18.1%
cool 11.1% 8.3% 5.0% 2.4% 6.1% 4.2% 5.6%
very cold 5.6% 4.9% 15.2% 8.3% 6.3%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
BIOCLIMATIC BUILDINGS CONVENTIONAL BUILDINGS
UMNO
Slightly cool to very cold ratings higher than slightly
warm to hot ratings by 33.3%.
KOMTAR
Slightly warm to hot ratings higher than slightly cool to
very cold ratings by 29.3%.
MESINIAGA
TIMA
IBM
LUTH
Mean = 4.31
Std Dev = 0.801
N = 62
Rating for thermal sensation in the office
Rating Bioclimatic Conventional Total
hot 9.2% 5.6%
too warm 8.2% 5.0%
slightly warm 8.1% 8.2% 8.1%
comfortable 64.5% 42.9% 51.3%
slightly cool 17.7% 18.4% 18.1%
cool 8.1% 4.1% 5.6%
very cold 1.6% 9.2% 6.3%
Total 100.0% 100.0% 100.0%
Mean = 4.02
Std Dev = 1.560
N = 98
Remarks:
The bioclimatic building type has rating mean 4.31 and standard deviation (SD) 0.801 whereas conventional
building type rating mean is 4.02 and SD 1.560. The peak distribution curve for conventional building is about
exactly at the neutral line whereas that for bioclimatic building is skews to the right or in other word is skew towards
the positive categories.
Figure 8.2: Thermal sensation rating in the office

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Table 8.7: Rating for satisfaction level towards thermal condition in the office
highly dissatisfied 3.0% 0.6%
dissatisfied 16.7% 8.3% 26.8% 9.1% 16.7% 14.4%
neutral 50.0% 12.5% 25.0% 26.8% 27.3% 33.3% 28.1%
satisfied 33.3% 50.0% 70.0% 41.5% 57.6% 50.0% 50.0%
very satisfied 25.0% 4.9% 3.0% 5.6%
highly satisfied 4.2% 5.0% 1.3%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
Positive ratings higher than negative ratings by
17.7%.
KOMTAR
19.6%.
MESINIAGA
70.9%.
TIMA
48.5%.
IBM
75.0%.
LUTH
33.3%.
Mean = 4.73
Std Dev = 0.872
N = 62
Rating for satisfaction towards thermal condition in the office
dissatisfied 8.1% 18.4% 14.4%
neutral 27.4% 28.6% 28.1%
satisfied 51.6% 49.0% 50.0%
very satisfied 9.7% 3.1% 5.6%
highly satisfied 3.2% 1.3%
Total 100.0% 100.0% 100.0%
(χ2
= 9.62, p = 0.087)
Mean = 4.34
Std Dev = 0.885
N = 98
Value df Asymp. Sig. (2-sided)
Pearson Chi-Square 9.624(a) 5 .087
Likelihood Ratio 10.746 5 .057
Linear-by-Linear Association 7.142 1 .008
N of Valid Cases 160
a 5 cells (41.7%) have expected count less than 5. The minimum expected count is .39.
Remarks:
The histogram and normal curve for the bioclimatic building type has rating mean 4.71 and SD, 0.872 whereas
conventional building type rating mean is 4.34 and SD, 0.885. The peak curve for bioclimatic type is skew further to
the right than that of conventional ones.
Figure 8.3: Satisfaction rating towards the thermal condition in the office

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Table 8.8: Rating frequency for quality of thermal condition at working station (office)
poor 5.6% 2.4% 3.0% 1.9%
fair 5.6% 8.3% 10.0% 19.5% 3.0% 12.5% 10.6%
adequate 44.4% 20.8% 45.0% 53.7% 48.5% 58.3% 46.3%
good 38.9% 58.3% 45.0% 24.4% 45.5% 29.2% 38.8%
excellent 5.6% 12.5% 2.5%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
33.3%.
KOMTAR
Positive ratings higher than negative ratings by 2.5%.
MESINIAGA
70.8%.
TIMA
39.5%.
IBM
35.0%.
LUTH
16.7%.
Table 8.9: Rating frequency for quality of thermal condition at lift lobby
poor 5.0% 2.4% 1.3%
fair 11.1% 20.0% 22.0% 16.7% 11.9%
adequate 33.3% 41.7% 45.0% 51.2% 69.7% 58.3% 51.9%
good 55.6% 50.0% 30.0% 24.4% 30.3% 25.0% 33.8%
excellent 8.3% 1.3%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
44.5%.
KOMTAR
Positive ratings are equal to negative ratings at
24.4%.
MESINIAGA
58.3%.
TIMA
30.3%.
IBM
LUTH
Table 8.10: Rating frequency for quality of thermal condition at corridor
poor 4.9% 4.2% 1.9%
fair 35.0% 19.5% 16.7% 11.9%
adequate 55.6% 45.8% 25.0% 56.1% 60.6% 58.3% 51.9%
good 38.9% 45.8% 40.0% 19.5% 39.4% 20.8% 32.5%
excellent 5.6% 8.4% 1.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
44.5%.
KOMTAR
Negative ratings higher than positive ratings by 4.9%.
MESINIAGA
54.2%.
TIMA
39.4%.
IBM
LUTH
Positive ratings equal to negative ratings at 20.8%.

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Quality of thermal condition at working station
poor 1.6% 2.0% 1.9%
fair 8.1% 12.2% 10.6%
adequate 35.5% 53.1% 46.3%
good 48.4% 32.7% 38.8%
excellent 6.5% 2.5%
Total 100.0% 100.0% 100.0%
Mean = 3.50
Std Dev = 0.805
N = 62
Mean = 3.16
Std Dev = 0.714
N = 98
Quality of thermal condition at the lift lobby
poor 1.6% 1.0% 1.3%
fair 9.7% 13.3% 11.9%
adequate 40.3% 59.2% 51.9%
good 45.2% 26.5% 33.8%
excellent 3.2% 1.3%
Total 100.0% 100.0% 100.0%
Mean = 3.39
Std Dev = 0.776
N = 62
Mean = 3.11
Std Dev = 0.656
N = 98
Quality of thermal condition at corridor/pathway
poor 3.1% 1.9%
fair 11.3% 12.2% 11.9%
adequate 41.9% 58.2% 51.9%
good 41.9% 26.5% 32.5%
excellent 4.8% 1.9%
Total 100.0% 100.0% 100.0%
Mean = 3.4
Std Dev = 0.757
N = 62
Mean = 3.08
Std Dev = 0.713
N = 98
Figure 8.4: Histogram and normal curve for thermal condition rating at several building
areas

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8.3 Indoor Ventilation
This section presents users’ perceptions of the indoor ventilation condition and their
satisfaction level with them. Perceptions were deliberated using several rating scales in the
survey that evaluate ventilation condition in office and communal areas in the building from
both natural and artificial sources. Overall condition and satisfaction towards the ventilation
element were also rated in this section.
Air Movement from Natural Ventilation
The rating of the overall air movement from natural ventilation in the office for all buildings
and in total percentage is shown in table 8.11. The perceptions of the overall air movement
from natural ventilation at the office show MESINIAGA and UMNO to be the highest and
the lowest rated for bioclimatic type whereas KOMTAR and TIMA are for conventional
type. Among all buildings, the highest rated is MESINIAGA where more than 50% rated it
slightly breezy and TIMA is the lowest rated building since more than 35% rated it slightly
still (see table 8.11). In addition, the collative rating for both types is shown in figure 8.5. In
bioclimatic buildings, more than half of respondents in UMNO, MESINIAGA and IBM
building considered the overall air movement from natural ventilation in their office to be
between “just right” and “slightly breezy”. A similar situation occurred in non-bioclimatic
buildings; KOMTAR, TIMA and LUTH. However, the statistics indicate that the overall air
movement from natural ventilation in bioclimatic building is highly rated by the respondents
in those buildings as compared to the rating obtained in non bioclimatic buildings (see
histogram and normal curve in figure 8.5).
Satisfaction towards natural ventilation in building
Table 8.12 shows the rating frequency for satisfaction level towards natural ventilation in the
office for all buildings. Figure 8.6 pictures the statistics in a histogram for both types of
building. More than 75% (2/3) of the respondents in each bioclimatic building feel neutral to
highly satisfied with the natural ventilation available in the office; 83.3% in UMNO, 91.7%
in MNIAGA, 85.0% in IBM. Quite similar perceptions were obtained in all conventional
buildings but fewer occupants were found to feel the same where only 72.5% in KOMTAR,
60.6% in TIMA and 71.0% in LUTH. In addition, more than 25% (1/4) of the respondents in
conventional buildings gave a negative rating, (27.5%) in KOMTAR, (40.4%) in TIMA and
(29.1%) in LUTH whereas less than twenty percent (1/5) of the respondents in bioclimatic
building gave a negative rating; UMNO (16.7%), MNIAGA (8.3%) and IBM (15.0%). In
simpler words, more than half of the respondents in bioclimatic building type choose

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positive categories whereas in conventional building types less than half of the respondents
do so.
Discussion:
The rating for overall natural ventilation air movement condition shows little difference
between bioclimatic and conventional types but when it comes to satisfaction towards
natural ventilation in the office the difference is obvious. Users in bioclimatic buildings are
relatively more satisfied than those in conventional buildings as mentioned above. More than
half (56.4%) of the respondents in bioclimatic buildings choose positive levels of satisfaction
towards natural ventilation in the office but only about 2/3 (38.1%) of total respondents in
conventional buildings do so. Less than 15% of the respondents in bioclimatic buildings
have negative level of satisfaction but more than a quarter (31.9%) in conventional buildings
do.
The statistics indicate that satisfaction toward availability of natural ventilation in
bioclimatic building is highly rated by the respondents in those buildings as compared to the
rating obtained in non bioclimatic buildings. This outcome gives an indication that the
respondents in bioclimatic building perceived better natural ventilation than in conventional
ones. However the chi-square value and asymptotic significance 2-sided for the cross
tabulation is (χ2
= 11.27, p = 0.127), which means it is statistically not significant (p > 0.05)
and it happens by chance (see figure 8.6).
Table 8.13 – 8.15 present the perception statistics of subjects towards availability of natural
ventilation at their work station, in the lift lobby and corridors in their building. The statistics
show that the availability of natural ventilation at those areas (office and communal) in
bioclimatic buildings is highly rated by the respondents as compared to the rating obtained in
non bioclimatic building. The histogram and normal curve in figure 8.7 explain the condition
further.

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Table 8.11: Rating for overall air movement from natural ventilation in the office
no info 2.5% 0.6%
much too still 3.0% 0.6%
too still 5.6% 5.0% 8.3% 3.1%
slightly still 11.1% 8.3% 15.0% 25.0% 36.4% 20.8% 21.4%
just right 38.9% 20.8% 25.0% 35.0% 45.5% 37.5% 34.6%
slightly breezy 33.3% 50.0% 30.0% 27.5% 15.2% 29.2% 29.6%
too breezy 11.1% 16.7% 30.0% 5.0% 4.2% 9.4%
much too breezy 4.2% 0.6%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
Slightly breezy to much too breezy ratings is higher
than slightly still to much too still ratings by 27.7%.
KOMTAR
Slightly still to much too still ratings is equal to slightly
breezy to much too breezy ratings at 32.5%.
MESINIAGA
Slightly breezy to much too breezy is higher than
slightly still to much too still ratings by 62.6%.
TIMA
Slightly still to much too still ratings is higher than
slightly breezy to much too breezy ratings by 24.2%.
IBM
LUTH
Mean = 4.68
Std Dev = 1.021
N = 62
Rating for air movement from natural ventilation in the office
no info 1.0% 0.6%
too still 1.6% 4.1% 3.1%
slightly still 11.3% 27.8% 21.4%
just right 27.4% 39.2% 34.6%
slightly breezy 38.7% 23.7% 29.6%
too breezy 19.4% 3.1% 9.4%
much too breezy 1.6% 0.6%
Total 100.0% 100.0% 100.0%
Mean = 3.87
Std Dev = 1.027
N = 97
Remarks:
The peak distribution curve for bioclimatic building type is skew to the right whereas the peak for conventional
building type is skew slightly to the left. Bioclimatic building type has rating mean 4.68 and SD, 1.021 whereas
conventional building type has rating mean 3.87 and SD, 1.027.
Figure 8.5: Natural ventilation rating in the office

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Table 8.12: Rating for satisfaction level towards natural ventilation in the office
no info 2.5% 0.6%
very dissatisfied 5.6% 5.0% 8.3% 3.1%
dissatisfied 11.1% 8.3% 15.0% 20.0% 36.4% 20.8% 20.1%
neutral 44.4% 25.0% 25.0% 30.0% 33.3% 25.0% 30.2%
satisfied 38.9% 50.0% 40.0% 35.0% 27.3% 41.7% 37.7%
very satisfied 12.5% 20.0% 7.5% 4.2% 6.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
22.2%.
KOMTAR
15.0%.
MESINIAGA
58.4%.
TIMA
Negative ratings higher than positive ratings by
12.1%.
IBM
45.0%.
LUTH
16.8%.
Mean = 4.56
Std Dev = 0.952
N = 62
Rating for satisfaction towards natural ventilation in the office
no info 1.0% 0.6%
very dissatisfied 1.6% 4.1% 3.1%
neutral 30.6% 29.9% 30.2%
satisfied 43.5% 34.0% 37.7%
Total 100.0% 100.0% 100.0%
(χ2
= 11.27, p = 0.127)
Mean = 4.01
Std Dev = 1.094
N = 97
Remarks:
The peak distribution curve for bioclimatic building type is slightly skew to the right whereas the peak for
conventional building type is about at the centre. The bioclimatic building type has rating mean 4.56 and SD, 0.952
and conventional building type has rating mean 4.01 and SD, 1.094.
Figure 8.6: Satisfaction rating towards natural ventilation in the office

16
Table 8.13: Quality of natural ventilation at work station
no info 2.4% 6.1% 1.9%
poor 5.6% 4.9% 12.1% 8.3% 5.6%
fair 5.6% 4.2% 30.0% 24.4% 21.2% 33.3% 20.6%
adequate 55.6% 50.0% 25.0% 46.3% 42.4% 33.3% 42.5%
good 33.3% 41.6% 45.0% 22.0% 18.2% 25.0% 28.8%
excellent 4.2% 0.6%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
22.1%.
KOMTAR
MESINIAGA
41.6%.
TIMA
21.2%.
IBM
15.0%.
LUTH
16.6%.
Table 8.14: Quality of natural ventilation at lift lobby
no info 2.4% 0.6%
poor 2.4% 9.1% 4.2% 3.1%
fair 11.1% 5.0% 29.3% 12.1% 37.5% 17.5%
adequate 44.4% 45.8% 30.0% 46.3% 60.6% 37.5% 45.6%
good 38.9% 37.5% 60.0% 19.5% 18.2% 20.8% 29.4%
excellent 5.6% 16.7% 5.0% 3.8%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
33.4%.
KOMTAR
14.6%.
MESINIAGA
54.2%.
TIMA
IBM
60.0%.
LUTH
20.9%.
Table 8.15: Quality of natural ventilation at corridor
no info 2.4% 0.6%
poor 9.8% 3.1% 12.5% 5.0%
fair 16.7% 35.0% 22.0% 21.9% 20.8% 19.5%
adequate 44.4% 45.8% 25.0% 48.8% 46.9% 50.0% 44.7%
good 33.3% 45.8% 40.0% 17.0% 28.1% 16.7% 28.3%
excellent 5.6% 8.4% 1.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
22.2%.
KOMTAR
17.2%.
MESINIAGA
54.2%.
TIMA
IBM
LUTH
16.6%.

17
Quality of natural ventilation at working station area
no info 3.1% 1.9%
poor 1.6% 8.2% 5.6%
fair 12.9% 25.5% 20.6%
adequate 43.5% 41.8% 42.5%
good 40.3% 21.4% 28.8%
excellent 1.6% 0.6%
Total 100.0% 100.0% 100.0%
Mean = 3.27
Std Dev = 0.772
N = 62
Mean = 2.70
Std Dev = 0.997
N = 98
Quality of natural ventilation at lift lobby area
no info 1.0% 0.6%
poor 5.1% 3.1%
fair 4.8% 25.5% 17.5%
adequate 40.3% 49.0% 45.6%
good 45.2% 19.4% 29.4%
excellent 9.7% 3.8%
Total 100.0% 100.0% 100.0%
Mean = 3.60
Std Dev = 0.735
N = 62
Mean = 2.81
Std Dev = 0.845
N = 98
Quality of natural ventilation at corridor/pathway
no info 1.0% 0.6%
poor 8.2% 5.0%
fair 16.1% 21.6% 19.5%
adequate 38.7% 48.5% 44.7%
good 40.3% 20.6% 28.3%
excellent 4.8% 1.9%
Total 100.0% 100.0% 100.0%
Mean = 3.34
Std Dev = 0.809
N = 62
Mean = 2.79
Std Dev = 0.901
N = 97
Figure 8.7: Histogram and normal curve for quality of natural ventilation rating at several
building areas

18
Air Conditioner Circulation
This section presents users’ perceptions of the overall air movement from air conditioner in
the office. The statistics in table 8.16 indicate that more than 60% (3/5) of the respondents in
each building considered the overall air movement from air conditioner in their office to be
between “just right” and “slightly breezy”; 72.3% in UMNO, 83.3% in MNIAGA, 85.0% in
IBM, 65.8% in KOMTAR, 84.9% in TIMA and 66.7% in LUTH building. Despite one of the
conventional buildings (TIMA) having about the same rating as all bioclimatic building, it
can still be seen that bioclimatic building is highly rated by the respondents in those
buildings as compared to the rating obtained in non bioclimatic buildings.
About 20% of the respondents in all bioclimatic buildings considered the overall air
movement from air conditioner in their office to be between “slightly still” and “too still”;
16.7% in UMNO, 12.5% in MNIAGA, 15.0% in IBM. More than thirty percent of the
respondents in two conventional buildings 34.2% in KOMTAR and 33.3% in LUTH
building considered the overall air movement from air conditioner in their office to be
between “slightly still” and “much too still”. Figure 8.8 shows the histogram and normal
curve for both type in collective.
Satisfaction towards Overall Air Conditioner Air Circulation in Building
The statistics in table 8.17 show that more than half of the respondents in each building,
except for KOMTAR, rated the overall air movement from air conditioner in their office
between satisfied to highly satisfied categories; 55.6% in UMNO, 79.2% in MNIAGA,
75.0% in IBM, 46.3% in KOMTAR, 63.3% in TIMA and 54.2% in LUTH building. Only
about 20% of the respondents in each non bioclimatic building were not satisfied with the
overall air movement from air conditioner in their office; 21.9% in KOMTAR, 20.9% in
LUTH and just 3.0% in TIMA building. A smaller percentage is obtained in each bioclimatic
building; 11.2% in UMNO, 4.2% in MNIAGA and none in IBM building.
Discussion:
When it comes to artificial ventilation in building where air circulation from an air
conditioner system is involved, there is no vast difference for both types of buildings where
the rating distribution varies from ‘too still’ to ‘too breezy’ for bioclimatic buildings whereas
in conventional buildings is varies from ‘much too still’ to ‘too breezy’. The artificial
ventilation in the tropics normally comes with cooler air as part of the strategies to reduce
indoor heat gain. Significantly the much breezier the air from the air conditioner, the much

19
cooler the space would be. In some cases the building might be over cooled as mentioned by
Ismail (2000).
It was anticipated that the occupants in conventional buildings might feel colder than those
in bioclimatic ones but the statistics indicate that satisfaction towards air conditioner air
circulation in bioclimatic building is highly rated by the respondents in those buildings as
compared to the rating obtained in non bioclimatic buildings. Figure 8.8 shows both types of
buildings have ‘just right’ category as the highest frequency; 64.5% (more than half) in
bioclimatic type and 49.0% (about half) in conventional type. However, more than half of
the respondent in both types of building are satisfied with the condition, with the highest
rating of 54.8% for bioclimatic buildings and 51.0% for conventional ones. Figure 8.9 shows
the overall rating distribution pattern varies from ‘highly satisfied’ to ‘very dissatisfied’
categories for bioclimatic buildings and ‘very satisfied’ to ‘highly dissatisfied’ for
conventional type. The peak for bioclimatic type is skew slightly to the right whereas the
peak for conventional type is almost exactly on the centre line but actually skew slightly to
the left. This clearly explains that the bioclimatic type have better rating than conventional
type in term of users’ satisfaction towards air conditioner circulation in building.
Furthermore, the chi-square value and asymptotic significance 2-sided for the cross
tabulation is (χ2
= 13.47, p = 0.036). It is statistically significant (p < 0.05) which means it
does not happen by chance (see figure 8.9).
Tables 8.18 to 8.20 present the statistics of the subject perception towards quality of air
circulation from air conditioner at users’ workstations, in the lift lobby and corridor. The
distribution presents the perception of the subjects towards the air circulation from the air
conditioner system in their building. The pattern indicates that the quality of air circulation
from air conditioner in the corridor in bioclimatic buildings is highly rated by the
building. However the rating at users’ workstation and in the lift lobby for all buildings
shows no clear advantage either for bioclimatic or conventional. In collective terms, this
voting pattern gives evidence that users in bioclimatic buildings are slightly more satisfied
than those in conventional buildings in terms of artificial ventilation condition and
satisfaction. It can be seen in many of the histograms and normal curves for each of the
features mentioned in this section.

20
Table 8.16: Rating for overall air circulation from air conditioner system in the office.
much too still 4.9% 8.3% 2.5%
too still 5.6% 4.9% 4.2% 2.5%
slightly still 11.1% 12.5% 15.0% 24.4% 3.0% 20.8% 15.0%
just right 55.5% 75.0% 60.0% 53.6% 39.4% 54.2% 55.0%
slightly breezy 16.7% 8.3% 25.0% 12.2% 45.5% 12.5% 20.6%
too breezy 11.1% 4.2% 12.1% 4.4%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
KOMTAR
MESINIAGA
Slightly breezy to much too breezy equal to slightly
still to much too still ratings is ratings at 12.5%.
TIMA
IBM
LUTH
Mean = 4.10
Std Dev = 0.740
N = 62
Rating for air conditioner air circulation condition in the office
too still 1.6% 3.1% 2.5%
slightly still 12.9% 16.3% 15.0%
just right 64.5% 49.0% 55.0%
slightly breezy 16.1% 23.5% 20.6%
too breezy 4.8% 4.1% 4.4%
Total 100.0% 100.0% 100.0%
Mean = 3.97
Std Dev = 1.030
N = 98
Remarks:
The peak for bioclimatic type is about to skew slightly to the right whereas the peak for conventional type is almost
exactly on the centre line but actually skew slightly to the left. The bioclimatic building type has rating mean 4.10
and SD, 0.740. Conventional building type has rating mean 3.97 and SD, 1.030.
Figure 8.8: Air conditioner air circulation rating condition in the office

21
Table 8.17: Satisfaction towards overall air conditioner air circulation in the office
highly dissatisfied 2.4% 4.2% 1.3%
very dissatisfied 5.6% 2.4% 4.2% 1.9%
dissatisfied 5.6% 4.2% 17.1% 3.0% 12.4% 8.1%
neutral 33.2% 16.6% 25.0% 31.8% 33.4% 25.0% 28.1%
satisfied 50.0% 62.5% 50.0% 43.9% 60.6% 50.0% 52.5%
very satisfied 5.6% 12.5% 20.0% 2.4% 3.0% 4.2% 6.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
44.4%.
KOMTAR
24.4%.
MESINIAGA
75.0%.
TIMA
60.6%.
IBM
75.0%.
LUTH
33.4%.
Mean = 4.84
Std Dev = 0.872
N = 62
Rating for satisfaction towards overall air conditioner circulation
very dissatisfied 1.6% 2.0% 1.9%
neutral 24.2% 30.6% 28.1%
satisfied 54.8% 51.0% 52.5%
Total 100.0% 100.0% 100.0%
(χ2
= 13.47, p = 0.036)
Mean = 4.36
Std Dev = 0.944
N = 98
Remarks:
The bioclimatic building type has rating mean 4.84 and SD, 0.872 whereas conventional building type has rating
mean 4.36 and SD, 0.944. The peak curves for bioclimatic types skew further to the right than the conventional
ones.
Figure 8.9: Satisfaction rating towards overall air conditioner circulation in the office

22
Table 8.18: Quality of air conditioner air circulation at working station
poor 2.4% 4.2% 1.3%
fair 16.7% 8.3% 5.0% 14.6% 9.1% 16.6% 11.9%
adequate 27.8% 12.5% 60.0% 63.4% 27.3% 54.2% 42.5%
good 55.6% 62.5% 35.0% 19.6% 57.6% 25.0% 40.6%
excellent 16.7% 6.1% 3.8%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
38.9%.
KOMTAR
MESINIAGA
70.9%.
TIMA
54.6%.
IBM
30.0%.
LUTH
Table 8.19: Quality of air conditioner air circulation at lift lobby
poor 2.4% 4.2% 1.3%
fair 16.7% 4.2% 35.0% 19.6% 3.0% 20.8% 15.6%
adequate 50.0% 25.0% 40.0% 63.4% 45.5% 62.5% 49.4%
good 33.3% 58.3% 20.0% 14.6% 51.5% 12.5% 31.3%
excellent 12.5% 5.0% 2.5%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
Positive ratings higher than Negative ratings by
16.6%.
KOMTAR
MESINIAGA
66.6%.
TIMA
48.5%.
IBM
10.0%.
LUTH
12.5%.
Table 8.20: Quality of air conditioner air circulation at corridor
poor 5.0% 2.4% 4.2% 1.9%
fair 5.6% 19.6% 6.1% 20.8% 10.0%
adequate 66.6% 37.5% 70.0% 63.4% 42.4% 58.3% 55.6%
good 27.8% 54.2% 20.0% 14.6% 51.5% 16.7% 30.6%
excellent 8.3% 5.0% 1.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
22.2%.
KOMTAR
MESINIAGA
62.5%.
TIMA
45.4%.
IBM
20.0%.
LUTH

23
Quality of artificial ventilation in workstation
poor 2.0% 1.3%
fair 9.7% 13.3% 11.9%
adequate 32.3% 49.0% 42.5%
good 51.6% 33.7% 40.6%
excellent 6.5% 2.0% 3.8%
Total 100.0% 100.0% 100.0%
Mean = 3.55
Std Dev = 0.761
N = 62
Mean = 3.20
Std Dev = 0.773
N = 98
Quality of artificial ventilation at lift lobby area
poor 2.0% 1.3%
fair 17.7% 14.3% 15.6%
adequate 37.1% 57.1% 49.4%
good 38.7% 26.5% 31.3%
excellent 6.5% 2.5%
Total 100.0% 100.0% 100.0%
Mean = 3.34
Std Dev = 0.848
N = 62
Mean = 3.08
Std Dev = 0.699
N = 98
Quality of artificial ventilation at corridor/pathway
poor 1.6% 2.0% 1.9%
fair 1.6% 15.3% 10.0%
adequate 56.5% 55.1% 55.6%
good 35.5% 27.6% 30.6%
excellent 4.8% 1.9%
Total 100.0% 100.0% 100.0%
Mean = 3.40
Std Dev = 0.689
N = 62
Mean = 3.08
Std Dev = 0.713
N = 98
Figure 8.10: Histogram and normal curve for quality of artificial ventilation (air conditioner)
rating at several building areas

24
8.4 ASHRAE Thermal Comfort Program Result
This program was developed by Environmental Analytics (Berkeley, CA) for The American
Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) under RP-
781. The program predicts human thermal response to the environment using several thermal
comfort models, including PMV-PPD, ET*-DISC. This software calculates the predicted
thermal comfort for a human at a point in space. A few things about the thermal environment
of the space and a few things about the person in that environment are needed as input data
for the programs to run.
A seven-point psychophysical scale of warmth. Thermal comfort scale - A seven point ordinal scale of
comfort and warmth.
+3 Hot +3 Much too warm
+2 Warm +2 Too warm
+1 Slightly warm +1 Comfortably warm
0 Neutral 0 Comfortable
-1 Slightly cool -1 Comfortably cool
-2 Cool -2 Too cool
-3 Cold -3 Much too cool
Thermal Sensation (TSENS) and Predicted Mean Vote (PMV) is a predicted vote on the
seven-point thermal sensation scale. Thermal Comfort Scales and Thermal sensation scale,
also referred to as the ASHRAE scale, are show above. Predicted Mean Vote PMV is an
index that predicts the mean value of the votes of a large group of persons on the above
seven point thermal sensation scale. Predicted Percentage of Dissatisfied PPD is an index
that predicts the percentage of thermally dissatisfied people (percentage of a large group of
people voting hot, warm, cool or cold). Beside the prediction of the Predicted Mean Vote
(PMV) and the Predicted Percentage of Dissatisfied (PPD), the real vote of the users was
registered in the questionnaires, making it possible to evaluate the office situations in both
types of buildings (bioclimatic and conventional). This method helps in the prediction of
comfort and acts as a guide to modifying those spaces. The result from this model shows that
the status for all buildings is comfortable and the remarks for UMNO, IBM, TIMA and
LUTH is in ISO whereas for MESINIAGA and KOMTAR is above ISO standard. The ideal
condition for all building is based on Humphreys’ neutral temperature TN(H) of 21.9°C,
whereas if based on Auliciem’s neutral temperature TN(A) for UMNO and LUTH it should
be at 22.6°C, for MESINIAGA and KOMTAR at 23.1°C, for IBM at 23.0°C, and for TIMA
at 22.3°C (see table 8.21 – A. Result mean). This will led to a reduction of 1 to 3°C of the
existing temperature in each building in order to achieve the comfort conditions based on the
TN recommended in this model. Detailed output data is summarised in table (8.22 – 8.29).

25
Table 8.21: ASHRAEE thermal comfort program result (summary)
A. Result (Mean)
Environmental
Measurement UMNO MESINIAGA IBM KOMTAR TIMA LUTH
ET (°C) 23.7 24.9 24.6 24.8 23.2 23.8
SET (°C) 25.1 26.5 25.5 26 25.1 25
TSENS 0 0.2 0.1 0.2 0 0
DISC 0 0.4 0.1 0.2 0 0
PMV 0.35 0.64 0.49 0.57 0.31 0.34
PPD (%) 8 14 10 12 7 7
PD (%) 12 10 11 10 12 12
PS (%) 61 46 48 46 68 61
TS -0.3 0 -0.1 0 -0.4 -0.3
TN (H) 21.9 21.9 21.9 21.9 21.9 21.9
TN (A) 22.6 23.1 23.0 23.1 22.3 22.6
Status Comfortable Comfortable Comfortable Comfortable Comfortable Comfortable
Remarks In ISO Above ISO In ISO Above ISO In ISO In ISO
B. Result (Minimum)
Environmental
ET (°C) 22.9 24.1 24.1 24.3 22.6 23.1
SET (°C) 22.3 23.4 23.3 23.6 21.8 22.4
TSENS -0.2 -0.1 -0.1 -0.1 -0.2 -0.2
DISC -0.2 -0.1 -0.1 -0.1 -0.2 -0.2
PMV -1 -0.61 -0.63 -0.54 -1.13 -0.95
PPD (%) 26 13 13 11 32 24
PD (%) 12 11 11 11 13 12
PS (%) 67 52 53 49 71 65
TS -0.5 -0.2 -0.2 -0.1 -0.9 -0.4
TN (H) 21.9 21.9 21.9 21.9 21.9 21.9
TN (A) 22.3 22.9 22.8 23 22.1 22.4
Status
(Cool)
Comfortable
(Cool)
Comfortable
Comfortable Comfortable Comfortable Comfortable
Remarks Below ISO Below ISO Below ISO Below ISO Below ISO Below ISO
C. Result (Maximum)
Environmental
ET (°C) 25.1 26.4 25.8 25.9 24.6 25.2
SET (°C) 30.2 32.4 31.3 30.3 30.3 29.7
TSENS 0.7 1 0.9 0.8 0.7 0.7
DISC 1.5 2.3 1.9 1.5 1.5 1.3
PMV 1.1 1.37 1.26 1.21 1.06 1.07
PPD (%) 31 44 38 36 29 29
PD (%) 11 10 10 10 12 11
PS (%) 54 39 44 42 63 54
TS -0.1 0.2 0.1 0.1 -0.3 -0.1
TN (H) 21.9 21.9 21.9 21.9 21.9 21.9
TN (A) 22.8 23.4 23.2 23.3 22.5 22.8
Status
Slightly Un-
comfortable
Too Humid
(Warm) Un-
comfortable
Un-
comfortable
Comfortable
Slightly Un-
comfortable
Slightly Un-
comfortable
Remarks Above ISO Above ISO Above ISO Above ISO Above ISO Above ISO

26
Table 8.22: ATCP input data for bioclimatic buildings
Environmental Measurement UMNO MESINIAGA IBM
Measured Parameters
Lower
Zone
Middle
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Higher
Zone
Higher
Zone Building
Average
7th Floor
13th
Floor
19th
Floor
3rd Floor 6th Floor
11th
Floor
6th Floor
10th
Floor
20th
Floor
22nd
Floor
1. Air Temp (°C)
Min 22.1 23.2 23.1 22.9 23.9 24.1 24.1 24.1 23.2 25.2 24.2 23.4 24.0
Max 23.5 24.4 23.8 23.9 24.8 26.1 24.7 25.1 23.7 26.6 25.4 23.8 24.7
Mean 23.1 23.6 23.3 23.4 24.2 25.1 24.4 24.6 23.5 25.7 24.8 23.6 24.4
2. MRT Link TA
(°C)
Min 22.1 23.2 23.1 22.9 23.9 24.1 24.1 24.1 23.2 25.2 24.2 23.4 24.0
Max 23.5 24.4 23.8 23.9 24.8 26.1 24.7 25.1 23.7 26.6 25.4 23.8 24.7
Mean 23.1 23.6 23.3 23.4 24.2 25.1 24.4 24.6 23.5 25.7 24.8 23.6 24.4
3. Air Velocity
(m/s)
Min 0.07 0.06 0.05 0.07 0.07 0.06 0.05 0.06 0.03 0.04 0.03 0.04 0.04
Max 0.16 0.12 0.16 0.14 0.13 0.11 0.12 0.11 0.11 0.12 0.14 0.08 0.10
Mean 0.09 0.09 0.08 0.09 0.09 0.08 0.07 0.08 0.07 0.07 0.07 0.06 0.07
4. Relative
Humidity (%)
Min 54.3 51.6 51.5 54.2 54.3 50.2 53.4 53.3 58.8 51.3 51.2 50.7 53.5
Max 65.8 69.4 69.1 68.1 67.3 61.4 65.6 64.8 69.1 67.8 62.0 61.3 65.1
Mean 59.9 59.7 59.7 59.8 59.1 53.4 58.7 57.1 62.3 58.4 56.2 54.9 57.9
5. Metabolic
Rate (met)
Min 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
Max 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7
Mean 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35
6. Clothing Level
(clo)
Min 0.57 0.55 0.55 0.55 0.54 0.58 0.61 0.54 0.57 0.54 0.61 0.54 0.54
Max 0.99 0.63 0.78 0.99 1.14 1.06 0.79 1.14 0.63 1.06 0.78 0.61 1.06
Mean 0.76 0.60 0.67 0.68 0.71 0.70 0.71 0.71 0.59 0.67 0.67 0.57 0.62
1. The level of occupants’ activity in the office spaces varies from reading, sitting, writing, typing, filing and walking about. Therefore the metabolic rate varies from 1.0 to 1.7 with an average metabolic rate of 1.35.
(ASHRAE Handbook: 1993).
2. The air velocity obtained from measurement varies from 0.03 m/s to 0.16 m/s (all buildings) and the minimum air velocity input in ATCP is 0.10m/s. Therefore the indoor air velocity in this calculation is set as
constant at 0.10m/s.

27
Table 8.23: ATCP input data for conventional buildings
Environmental Measurement KOMTAR TIMA LUTH
Measured Parameters
Lower
Zone
Middle
Zone
Higher
Zone Building
Average
Lower
Zone
Middle Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Higher
Zone Building
Average22nd
Floor
35th
Floor
51st Floor 8th Floor
17th
Floor
18th
Floor
24th Floor
12th
Floor
25th
Floor
36th
Floor
1. Air Temp (°C)
Min 24.2 24.6 24.0 24.3 22.4 22.5 22.5 22.5 22.5 22.7 22.6 23.2 23.0
Max 25.0 25.2 24.5 24.9 23.1 23.2 23.2 23.3 23.2 23.5 23.7 24.5 23.9
Mean 24.6 24.8 24.2 24.6 22.8 22.8 22.9 22.9 22.8 23.1 23.2 24.0 23.4
2. MRT Link TA
(°C)
Min 24.2 24.6 24.0 24.3 22.4 22.5 22.5 22.5 22.5 22.7 22.6 23.2 23.0
Max 25.0 25.2 24.5 24.9 23.1 23.2 23.2 23.3 23.2 23.5 23.7 24.5 23.9
Mean 24.6 24.8 24.2 24.6 22.8 22.8 22.9 22.9 22.8 23.1 23.2 24.0 23.4
3. Air Velocity
(m/s)
Min 0.04 0.03 0.05 0.04 0.03 0.03 0.02 0.04 0.04 0.05 0.04 0.05 0.05
Max 0.08 0.09 0.09 0.08 0.11 0.10 0.11 0.07 0.08 0.08 0.07 0.11 0.09
Mean 0.05 0.06 0.07 0.06 0.05 0.05 0.04 0.05 0.05 0.07 0.06 0.08 0.07
4. Relative
Humidity (%)
Min 51.3 48.7 54.6 51.8 62.4 57.8 59.4 56.6 59.2 58.7 56.9 59.3 58.6
Max 62.7 63.4 65.1 63.7 72.8 71.3 68.1 70.8 70.8 72.2 71.6 66.6 70.1
Mean 56.7 55.5 59.6 57.3 66.6 63.7 63.4 63.0 64.2 65.0 63.8 62.8 63.9
5. Metabolic
Rate (met)
Min 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
Max 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7
Mean 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35
6. Clothing Level
(clo)
Min 0.54 0.57 0.54 0.54 0.54 0.72 0.54 0.64 0.54 0.54 0.63 0.54 0.54
Max 0.93 0.72 0.79 0.93 0.88 0.99 0.93 1.06 1.06 0.93 0.74 0.72 0.93
Mean 0.66 0.67 0.61 0.65 0.67 0.81 0.67 0.90 0.73 0.65 0.69 0.63 0.66
1. The level of occupants’ activity in the office spaces varies from reading, sitting, writing, typing, filing and walking about. Therefore the metabolic rate varies from 1.0 to 1.7 with an average metabolic rate of 1.35.
(ASHRAE Handbook: 1993).
2. The air velocity obtained from measurement varies from 0.03 m/s to 0.16 m/s (all buildings) and the minimum air velocity input in ATCP is 0.10m/s. Therefore the indoor air velocity in this calculation is set as
constant at 0.10m/s.

28
Table 8.24: ATCP output data for UMNO (bioclimatic)
Results
Minimum Maximum Mean
Lower Zone
Middle
Zone
Higher Zone
Building
Average
Lower Zone Middle Zone Higher Zone
Building
Average
Lower Zone
Middle
Zone
Higher Zone
Building
Average
7th Floor 13th Floor 19th Floor 7th Floor 13th Floor 19th Floor 7th Floor 13th Floor 19th Floor
1. ET (°C) 22.1 23.2 23.2 22.9 24.5 25.3 24.8 25.1 23.4 23.8 23.6 23.7
2. SET (°C) 21.6 22.6 22.5 22.3 29.7 27.0 28.1 30.2 25.6 24.6 24.9 25.1
3. TSENS -0.3 -0.2 -0.2 -0.2 0.6 0.3 0.4 0.7 0.0 0.0 0.0 0.0
4. DISC -0.3 -0.2 -0.2 -0.2 1.3 0.5 0.8 1.5 0.1 0.0 0.0 0.0
5. PMV -1.22 -0.91 -0.88 -1.00 1.03 0.89 0.92 1.10 0.39 0.28 0.31 0.35
6. PPD (%) 36 22 21 26 27 22 23 31 8 7 7 8
7. PD (%) 13 12 12 12 12 11 11 11 12 11 12 12
8. PS (%) 76 63 64 67 59 48 56 54 64 58 62 61
9. TS -0.7 -0.4 -0.4 -0.5 -0.2 0.0 -0.1 -0.1 -0.4 -0.3 -0.3 -0.3
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 21.9 22.5 22.4 22.3 22.6 23.0 22.7 22.8 22.4 22.6 22.5 22.6
12. Status
Cool
Comfortable
Comfortable Comfortable
Cool
Comfortable
Slightly
Uncomfortable
Too Humid
Slightly
Uncomfortable
Slightly
Uncomfortable
Slightly
Uncomfortable
13. Remarks
Below
ISO
Below ISO
Below
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
In
ISO
In
ISO
In
ISO
In
ISO

29
Table 8.25: ATCP output data for MESINIAGA (bioclimatic)
Results
Building
Average
Building
Average
Building
Average
3rd Floor 6th Floor 11th Floor 3rd Floor 6th Floor 11th Floor 3rd Floor 6th Floor 11th Floor
1. ET (°C) 23.9 24.1 24.1 24.1 26.2 27.1 25.7 26.4 24.5 25.2 24.7 24.9
2. SET (°C) 23.2 23.7 23.9 23.4 32.2 32.3 28.9 32.4 26.2 26.8 26.4 26.5
3. TSENS -0.1 -0.1 -0.1 -0.1 1.0 1.1 0.6 1.0 0.2 0.3 0.2 0.2
4. DISC -0.1 -0.1 -0.1 -0.1 2.3 2.3 1.1 2.3 0.3 0.4 0.3 0.4
5. PMV -0.67 -0.53 -0.44 -0.61 1.33 1.46 1.08 1.37 0.56 0.72 0.61 0.64
6. PPD (%) 14 11 9 13 42 49 30 44 12 16 13 14
7. PD (%) 11 11 11 11 10 9 10 10 11 10 11 10
8. PS (%) 54 52 52 52 43 26 44 39 51 39 48 46
9. TS -0.2 -0.2 -0.2 -0.2 0.1 0.4 0.1 0.2 -0.1 0.1 -0.1 -0.0
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 22.8 22.9 22.9 22.9 23.2 23.8 23.2 23.4 22.9 23.4 23.0 23.1
12. Status Comfortable Comfortable Comfortable Comfortable
Too Humid
Warm
Uncomfortable
Too Humid
Warm
Uncomfortable
Too Humid
Slightly
Uncomfortable
Too Humid
Warm
Uncomfortable
13. Remarks
Below
ISO
Below
ISO
In
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO

30
Table 8.26: ATCP output data for IBM (bioclimatic)
Results
Lower
Zone
Middle
Zone
Higher
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Higher
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Higher
Zone
Higher
Zone Building
Average
6th Floor
10th
Floor
20th
Floor
22nd
Floor
6th Floor
10th
Floor
20th
Floor
22nd
Floor
6th Floor
10th
Floor
20th
Floor
22nd
Floor
1. ET (°C) 23.3 25.2 24.2 23.4 24.1 24.5 28.3 26.2 24.2 25.8 23.8 26.1 25.0 23.7 24.6
2. SET (°C) 22.8 24.5 24.0 22.7 23.3 26.3 33.3 29.3 25.9 31.3 24.4 27.3 26.3 24.2 25.5
3. TSENS -0.2 -0.1 -0.1 -0.2 -0.1 0.2 1.2 0.7 0.1 0.9 0.0 0.4 0.2 0.0 0.1
4. DISC -0.2 -0.1 -0.1 -0.2 -0.1 0.3 2.8 1.2 0.2 1.9 0.0 0.6 0.3 0.0 0.1
5. PMV -0.80 -0.23 -0.42 -0.87 -0.63 0.75 1.59 1.18 0.71 1.26 0.25 0.85 0.63 0.21 0.49
6. PPD (%) 18 6 9 21 13 17 56 34 16 38 6 20 13 6 10
7. PD (%) 12 10 11 12 11 11 8 9 11 10 12 9 10 11 11
8. PS (%) 63 38 51 61 53 57 20 35 56 44 59 32 43 58 48
9. TS -0.4 0.1 -0.2 -0.4 -0.2 -0.2 0.6 0.2 -0.2 0.1 -0.3 0.3 0.0 -0.3 -0.1
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 22.5 23.4 22.9 22.6 22.8 22.7 24.1 23.5 22.7 23.2 22.6 23.7 23.2 22.6 23.0
12. Status
Comforta
ble
Comforta
ble
Not
enough
air
movemen
t
Comforta
ble
Comforta
ble
Comfortabl
e
Comforta
ble
Too
Humid
Warm
Very
Uncomfo
rtable
Too
Humid
Warm
Slightly
Uncomfo
rtable
Comforta
ble
Uncomforta
ble
Comforta
ble
Warm
Slightly
Uncomfo
rtable
Comforta
ble
Comforta
ble
Comfortabl
e
13. Remarks
Below
ISO
In
ISO
In
ISO
Below
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
In
ISO
Above
ISO
Above
ISO
In
ISO
In
ISO

31
Table 8.27: ATCP output data for KOMTAR (conventional)
Results
Building
Average
Building
Average
Building
Average
22nd Floor 35th Floor 51st Floor 22nd Floor 35th Floor 51st Floor 22nd Floor 35th Floor 51st Floor
1. ET (°C) 24.2 24.6 24.1 24.3 25.9 26.0 25.4 25.9 24.8 25.0 24.5 24.8
2. SET (°C) 23.5 24.1 23.3 23.6 30.3 28.5 28.6 30.3 26.1 26.3 25.3 26.0
3. TSENS -0.1 -0.1 -0.1 -0.1 0.8 0.6 0.6 0.8 0.2 0.2 0.0 0.2
4. DISC -0.1 -0.1 -0.1 -0.1 1.5 1.0 1.0 1.5 0.3 0.3 0.1 0.2
5. PMV -0.59 -0.39 -0.63 -0.54 1.22 1.10 1.04 1.21 0.58 0.63 0.44 0.57
6. PPD (%) 12 8 13 11 36 30 28 36 12 13 9 12
7. PD (%) 11 10 11 11 10 10 10 10 10 10 11 10
8. PS (%) 51 46 53 49 40 38 47 42 46 43 51 46
9. TS -0.2 -0.1 -0.2 -0.1 0.1 0.2 0.0 0.1 -0.0 0.0 -0.1 -0.0
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 22.9 23.1 22.8 23.0 23.3 23.4 23.1 23.3 23.1 23.2 22.9 23.1
12. Status Comfortable
Comfortable
Not enough
air
movement
Comfortable Comfortable Uncomfortable
Too Humid
Slightly
Uncomfortable
Slightly
Uncomfortable
Comfortable Comfortable Comfortable Comfortable Comfortable
13. Remarks
Below
ISO
In
ISO
Below
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
In
ISO
Above
ISO

32
Table 8.28: ATCP output data for TIMA (conventional)
Results
Lower Zone
Middle
Zone
Middle
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Middle
Zone
Higher
Zone Building
Average
Lower
Zone
Middle
Zone
Middle
Zone
Higher
Zone Building
Average
8th Floor
17th
Floor
18th
Floor
24th
Floor
8th Floor
17th
Floor
18th
Floor
24th
Floor
8th Floor
17th
Floor
18th
Floor
24th
Floor
1. ET (°C) 22.5 22.6 22.6 22.6 22.6 24.3 24.5 24.2 24.7 24.6 23.2 23.2 23.2 23.4 23.2
2. SET (°C) 21.8 23.1 21.8 22.5 21.8 28.6 29.7 28.9 30.4 30.3 24.6 25.9 24.6 26.7 25.1
3. TSENS -0.2 -0.1 -0.2 -0.2 -0.2 0.5 0.6 0.5 0.7 0.7 0.0 0.1 0.0 0.2 0.0
4. DISC -0.2 -0.1 -0.2 -0.2 -0.2 0.9 1.3 1.0 1.5 1.5 0.0 0.2 0.0 0.4 0.0
5. PMV -1.14 -0.68 -1.13 -0.88 -1.13 0.91 1.00 0.94 1.07 1.06 0.24 0.41 0.24 0.53 0.31
6. PPD (%) 33 15 32 21 32 22 26 24 29 29 6 9 6 11 7
7. PD (%) 13 13 13 13 13 12 12 12 12 12 12 12 12 12 12
8. PS (%) 73 71 71 71 71 64 63 63 62 63 68 68 67 67 68
9. TS -0.6 -0.6 -0.6 -0.6 -0.9 -0.3 -0.3 -0.3 -0.3 -0.3 -0.4 -0.4 -0.4 -0.4 -0.4
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 22.1 22.1 22.1 22.1 22.1 22.4 22.5 22.5 22.5 22.5 22.3 22.3 22.3 22.3 22.3
12. Status
Cool
Comfortable
Cool
Comforta
ble
Cool
Comforta
ble
Cool
Comforta
ble
Cool
Comfortabl
e
Slightly
Uncomfo
rtable
Slightly
Uncomfo
rtable
Slightly
Uncomfo
rtable
Uncomfo
rtable
Slightly
Uncomforta
ble
Comforta
ble
Comforta
ble
Comforta
ble
Comforta
ble
Comfortabl
e
13. Remarks
Below
ISO
Below
ISO
Below
ISO
Below
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
In
ISO
In
ISO
In
ISO
Above
ISO
In
ISO

33
Table 8.29: ATCP output data for LUTH (conventional)
Results
Building
Average
Building
Average
Building
Average
12th Floor 25th Floor 36th Floor 12th Floor 25th Floor 36th Floor 12th Floor 25th Floor 36th Floor
1. ET (°C) 22.8 22.7 23.3 23.1 24.8 24.8 25.4 25.2 23.4 23.6 24.4 23.8
2. SET (°C) 22.0 22.6 22.6 22.4 29.4 27.7 28.0 29.7 24.7 25.1 25.3 25.0
3. TSENS -0.2 -0.2 -0.2 -0.2 0.6 0.4 0.5 0.7 0.0 0.0 0.0 0.0
4. DISC -0.2 -0.2 -0.2 -0.2 1.2 0.7 0.8 1.3 0.0 0.0 0.1 0.0
5. PMV -1.06 -0.87 -0.88 -0.95 1.01 0.88 0.99 1.07 0.27 0.34 0.44 0.34
6. PPD (%) 29 21 21 24 27 21 26 29 6 7 9 7
7. PD (%) 12 13 12 12 12 11 10 11 12 12 11 12
8. PS (%) 69 70 63 65 59 57 47 54 64 63 53 61
9. TS -0.5 -0.6 -0.4 -0.4 -0.2 -0.1 0.0 -0.1 -0.4 -0.3 -0.1 -0.3
10. TN (H) 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9 21.9
11. TN (A) 22.2 22.2 22.5 22.4 22.6 22.7 23.1 22.8 22.4 22.5 22.8 22.6
12. Status Comfortable
Cool
Comfortable
Comfortable Comfortable
Slightly
Uncomfortable
Too Humid
Slightly
Uncomfortable
Too Humid
Slightly
Uncomfortable
Slightly
Uncomfortable
13. Remarks
Below
ISO
Below
ISO
Below
ISO
Below
ISO
Above
ISO
Above
ISO
Above
ISO
Above
ISO
In
ISO
In
ISO
In
ISO
In
ISO

8.5 Indoor Lighting
This section presents users’ perceptions of the indoor lighting condition and their satisfaction
level with them. Perceptions were measured using several rating scales in the survey that
evaluate lighting conditions in several areas in the building. Overall condition and
satisfaction towards lighting element were also rated in this section.
Natural Lighting in Building
Table 8.30 shows the rating frequency for overall level of natural light in the office spaces of
all buildings. The statistics show that more than half of the respondents in each building,
except for IBM rated the overall natural lighting available in their office as between ‘just
nice and clear’ to ‘much too bright’ categories; 83.4% in UMNO, 79.1% in MNIAGA,
40.0% in IBM, 87.8% in KOMTAR, 57.6% in TIMA and 83.3% in LUTH building. The
statistics indicate that the rating for availability of natural light in bioclimatic building is
about the same as the rating obtained in non bioclimatic buildings. The results give an
indication that there is no clear advantage either for bioclimatic or conventional in terms of
availability of natural light in building as there is no major difference in the rating obtained
in those buildings (see figure 8.11).
Satisfaction with the Natural Light in the Office
This section indicates the satisfaction toward the availability of natural light in building. The
statistics in table 8.31 show that more than 40% of the respondents in each building rated
their satisfaction level towards the overall natural lighting available in their office as between
satisfied and highly satisfied; 44.5% in UMNO, 79.2% in MNIAGA, 45.0% in IBM, 58.6%
in KOMTAR, 48.5% in TIMA and 50.0% in LUTH building. The rating obtained in each
bioclimatic building (except for MESINIAGA) is about the same as that of none bioclimatic
building where more than 50% of the respondents in each building were neutral and satisfied
with the availability of natural light in their office building. KOMTAR is the most highly
rated building followed by UMNO and LUTH. Next is MESINIAGA and TIMA is the
lowest rated.
Figure 8.12 shows the rating pattern for satisfaction toward availability of natural lighting in
the office for both bioclimatic and conventional types of building. It shows that 2/5 of the
respondents in both types of building are satisfied (highest frequency) with the natural
lighting condition in their office by 40.3% for bioclimatic buildings and 44.9% for
conventional ones. This outcome gives an indication that the users’ perceptions of better

natural lighting in bioclimatic buildings compared with conventional ones is not really
substantiated. Furthermore, the chi-square value and asymptotic significance 2-sided for the
cross tabulation between building type and satisfaction with the natural lighting is (χ2
= 6.18,
p = 0.289). This means the crosstabulation is statistically not significant and it’s happen by
chance as (p > 0.05).
Artificial Lighting
This section presents users’ perceptions of the quality of several aspects of artificial lighting
condition and their satisfaction level with them. Table 8.35 shows the rating frequency for
overall level of artificial lighting in the office spaces for all buildings. Over 50% of the
respondents in each building considered the level of artificial lighting in their building as
‘just nice and clear’ and ‘slightly bright’; 77.9% in UMNO, 87.5% in MNIAGA, 70.0% in
IBM, 85.3% in KOMTAR, 66.6% in TIMA and 91.7% in LUTH building.
Figure 8.14 shows the collective rating for overall artificial lighting condition in both types
of building. More than half of the respondents in both types of building rated ‘just nice and
clear’ category and the balance ratings are scatted to others categories. There is no clear
advantage for either type having better overall level of artificial lighting available in office
building. The statistics indicate that all buildings have about the same level of artificial
lighting rated by the respondents in those buildings.
Satisfaction with the Artificial Lighting in Office
The rating obtained in bioclimatic buildings is about the same as that of none bioclimatic
buildings as shown in table 8.36. More than 50% of the respondents in each building are
neutral and satisfied with the availability of artificial light in their office building. There are
more than 10% of the respondents in each bioclimatic building who rated very satisfied and
highly satisfied; 11.1% in UMNO, 25.0% in MESINIAGA, 15.0% in IBM, whereas in
conventional building only about 7.3% in KOMTAR, none in TIMA and 12.5% in LUTH.
There is no negative rating for two conventional buildings (KOMTAR and LUTH) and one
in bioclimatic building (IBM). Figure 8.15 shows the rating distribution for satisfaction
towards the overall level of artificial lighting for both types of buildings. More than half of
the respondents in both types rated ‘satisfied’ category. 25% (1/4) of respondents in
bioclimatic type rated neutral whereas only 21% of respondents in conventional type did.
There is only a small percentage that rated between ‘dissatisfied’ and ‘very dissatisfied’
categories for both types and more for ‘very satisfied’ to ‘highly satisfied’ categories as
shown in the table. The chi-square value and asymptotic significance 2-sided for the cross

tabulation between building type and satisfaction with the artificial lighting is (χ2
= 9.99, p =
0.0.76). Again, the crosstabulation is statistically insignificant as p > 0.05 (see figure 8.15).
Tables 8.32 to 8.34 present the statistics for respondents’ perceptions of the quality of natural
light available at users’ workstation, in the lift lobby and corridor. Although there is no
major difference in the rating obtained for overall level of natural light, it was found that the
quality of natural light available at workstation, in the lift lobby, and corridor in bioclimatic
buildings is highly rated by the respondents in those buildings as compared to the rating
obtained in non bioclimatic building (see table 8.32 – 8.34 and figure 8.13). However, there
is no clear advantage either for bioclimatic or conventional when related to artificial lighting
in those areas (see tables 8.37 to 8.39 and figure 8.16).
Discussion:
If we refer to figure 8.11 natural lighting rating conditions for both bioclimatic and
conventional types of buildings show that there is a difference in categories selected by
respondents in both types of building. The rating distribution varies from ‘much too bright’
to ‘too dim’ for bioclimatic buildings whereas in conventional buildings it varies from ‘much
too bright’ to ‘much too dim’. Both types have highest rating falling into the ‘just nice and
clear’ category; 43.5% in bioclimatic and 59.2% in conventional. The balance of the ratings
scatters over the other categories and leads the distribution peaks of bioclimatic types to
skew slightly to the left whereas the conventional types skew slightly to the right, even
though they seem to be almost exactly at the same position (see figure 8.11).
Lighting levels on a desk, the width of the building and the height of the ceiling all affect
workers’ feelings of comfort and their productivity. In terms of running costs, however,
energy for lighting, which accounts for a large portion of the fuel bill for an office building,
can be greatly reduced by the use of daylight. Useful daylight penetrates 3 to 6 meters inside
a building from the windows. This is what is theoretically applied in most bioclimatic
buildings. However, based on the two distribution ratings obtained from the survey, the
belief that bioclimatic buildings have better natural lighting than conventional ones is not
substantiated in this study. The measurements for combined natural and artificial lighting in
all buildings show that all buildings have an average light level more than required (see
section 7.1.2). Designers have provided the appropriate need for visual comfort and it
depends on the users to control the level by any means; blinds, curtain or additional table
lamp is necessary to fit his/her comfort.

Table 8.30: Overall level of natural light in the office spaces
no info 2.4% 4.2% 1.3%
much too dim 3.0% 0.6%
too dim 4.2% 10.0% 12.1% 4.4%
slightly dim 16.7% 16.7% 50.0% 9.8% 27.3% 12.5% 20.6%
just nice and clear 44.3% 62.4% 20.0% 65.9% 45.5% 66.7% 53.1%
slightly bright 27.8% 12.5% 5.0% 2.4% 6.1% 7.5%
too bright 5.6% 4.2% 15.0% 7.3% 3.0% 8.3% 6.9%
much too bright 5.6% 12.2% 3.0% 8.3% 5.6%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
Slightly bright to much too bright ratings are higher
than slightly dim to much too dim ratings by 22.3%.
KOMTAR
Slightly bright to much too bright ratings higher than
slightly dim to much too dim ratings by 9.7%.
MESINIAGA
Slightly dim to much too dim ratings higher than
slightly bright to much too bright ratings by 4.2%.
TIMA
IBM
LUTH
Slightly bright to much too bright ratings equal with
slightly dim to much too dim ratings at 16.7%.
Mean = 3.98
Std Dev = 1.048
N = 62
Rating for natural lighting in the office
no info 2.0% 1.3%
much too dim 1.0% 0.6%
too dim 4.8% 4.1% 4.4%
slightly dim 27.4% 16.3% 20.6%
just nice and clear 43.5% 59.2% 53.1%
slightly bright 14.5% 3.1% 7.5%
too bright 8.1% 6.1% 6.9%
much too bright 1.6% 8.2% 5.6%
Total 100.0% 100.0% 100.0%
Mean = 4.04
Std Dev = 1.331
N = 98
Remarks:
mean 4.04 and SD, 1.331.
Figure 8.11: Natural lighting rating in the office

Table 8.31: Rating for satisfaction level towards natural light in building.
no info 2.4% 4.2% 1.3%
dissatisfied 11.1% 12.5% 15.0% 2.4% 18.2% 8.3% 10.6%
neutral 44.4% 8.3% 40.0% 36.6% 33.3% 37.5% 33.1%
satisfied 27.8% 45.8% 45.0% 51.3% 39.4% 41.7% 43.1%
very satisfied 16.7% 29.2% 7.3% 9.1% 8.3% 11.3%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
33.4%.
KOMTAR
58.6%.
MESINIAGA
66.7%.
TIMA
30.3%.
IBM
30.0%.
LUTH
41.7%.
Mean = 4.65
Std Dev = 0.960
N = 62
Rating for satisfaction towards the natural light in the office
no info 2.0% 1.3%
neutral 29.0% 35.7% 33.1%
satisfied 40.3% 44.9% 43.1%
Total 100.0% 100.0% 100.0%
(χ2
= 6.18, p = 0.289)
Mean = 4.44
Std Dev = 1.006
N = 98
Remarks:
Although they seem like to be at the same position, the distribution peak for bioclimatic buildings type skews to the
right further than conventional type. The bioclimatic building type has rating mean 4.65 and SD, 0.960 whereas
Figure 8.12: Satisfaction rating towards the natural lighting in the office

Table 8.32: Quality of natural light at working station
no info 2.4% 4.2% 1.3%
poor 5.0% 0.6%
fair 11.1% 8.3% 25.0% 2.4% 9.1% 8.1%
adequate 44.4% 25.0% 15.0% 61.0% 51.5% 58.3% 45.6%
good 38.9% 58.4% 45.0% 34.2% 39.4% 37.5% 41.3%
excellent 5.6% 8.3% 10.0% 3.1%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
33.4%.
KOMTAR
32.8%.
MESINIAGA
58.3%.
TIMA
30.3%.
IBM
25.0%.
LUTH
37.5%.
Table 8.33: Quality of natural light at lift lobby
no info 2.4% 4.2% 1.3%
poor 5.0% 2.4% 3.0% 4.2% 2.5%
fair 16.7% 4.2% 20.0% 24.4% 15.2% 25.0% 18.1%
adequate 50.0% 16.6% 40.0% 53.7% 42.4% 37.6% 41.3%
good 33.3% 54.2% 20.0% 17.1% 36.4% 29.2% 30.6%
excellent 25.0% 15.0% 3.0% 6.3%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
16.6%.
KOMTAR
MESINIAGA
75.0%.
TIMA
21.2%.
IBM
10.0%.
LUTH
Positive ratings equal to negative ratings at 29.2%.
Table 8.34: Quality of natural light at corridor
no info 2.4% 4.2% 1.3%
poor 3.0% 0.6%
fair 22.2% 15.0% 7.3% 12.2% 8.3% 10.0%
adequate 38.9% 29.2% 50.0% 73.2% 42.4% 70.8% 53.1%
good 33.3% 58.3% 30.0% 17.1% 42.4% 16.7% 31.9%
excellent 5.6% 12.5% 5.0% 3.1%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
16.7%.
KOMTAR
MESINIAGA
70.8%.
TIMA
27.3%.
IBM
20.0%.
LUTH

Quality of natural light at workstation
no info 2.0% 1.3%
poor 1.6% 0.6%
fair 14.5% 4.1% 8.1%
adequate 27.4% 57.1% 45.6%
good 48.4% 36.7% 41.3%
excellent 8.1% 3.1%
Total 100.0% 100.0% 100.0%
Mean = 3.47
Std Dev = 0.900
N = 62
Mean = 3.27
Std Dev = 0.726
N = 98
Quality of natural light at lift lobby
no info 2.0% 1.3%
poor 1.6% 3.1% 2.5%
fair 12.9% 21.4% 18.1%
adequate 33.9% 45.9% 41.3%
good 37.1% 26.5% 30.6%
excellent 14.5% 1.0% 6.3%
Total 100.0% 100.0% 100.0%
Mean = 3.50
Std Dev = 0.954
N = 62
Mean = 2.95
Std Dev = 0.912
N = 98
Quality of natural light at corridor/pathway
no info 2.0% 1.3%
poor 1.0% 0.6%
fair 11.3% 9.2% 10.0%
adequate 38.7% 62.2% 53.1%
good 41.9% 25.5% 31.9%
excellent 8.1% 3.1%
Total 100.0% 100.0% 100.0%
Mean = 3.47
Std Dev = 0.804
N = 62
Mean = 3.08
Std Dev = 0.755
N = 98
Figure 8.13: Histogram and normal curve for quality of natural lighting rating at several
building areas

Table 8.35: Overall level of artificial lighting in the office
much too dim 5.0% 6.1% 1.9%
too dim 3.0% 0.6%
slightly dim 11.1% 4.2% 20.0% 6.1% 5.6%
just nice and clear 55.7% 75.0% 45.0% 82.9% 57.5% 87.5% 69.4%
slightly bright 22.2% 12.5% 25.0% 2.4% 9.1% 4.2% 10.6%
too bright 5.6% 8.3% 12.2% 18.2% 8.3% 10.0%
much too bright 5.6% 5.0% 2.4% 1.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
KOMTAR
MESINIAGA
“Slightly bright” to “much too bright” ratings higher
than “slightly dim” to “much too dim” ratings by
16.6%.
TIMA
12.1%.
IBM
than “slightly dim” to “much too dim” ratings by 5.0%.
LUTH
12.5%.
Mean = 4.23
Std Dev = 0.948
N = 62
Rating for artificial lighting in the office
much too dim 1.6% 2.0% 1.9%
too dim 1.0% 0.6%
slightly dim 11.3% 2.0% 5.6%
just nice and clear 59.7% 75.5% 69.4%
slightly bright 19.4% 5.1% 10.6%
too bright 4.8% 13.3% 10.0%
much too bright 3.2% 1.0% 1.9%
Total 100.0% 100.0% 100.0%
Mean = 4.24
Std Dev = 0.931
N = 98
Remarks:
The distribution peaks for artificial lighting condition in both building types are slightly skew to the right and at almost
exactly at the same position. The bioclimatic building type has rating mean 4.23 and SD, 0.948 whereas
Figure 8.14: Artificial lighting rating in the office

Table 8.36: Rating frequency for satisfaction with the artificial lighting in office
dissatisfied 5.6% 4.2% 6.1% 2.5%
neutral 38.9% 4.2% 40.0% 19.5% 27.3% 16.7% 23.1%
satisfied 44.4% 66.7% 45.0% 73.2% 57.6% 70.8% 61.9%
very satisfied 11.1% 20.8% 15.0% 4.9% 8.3% 8.8%
highly satisfied 4.2% 2.4% 4.2% 1.9%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
44.9%.
KOMTAR
80.5%.
MESINIAGA
87.5%.
TIMA
42.4%.
IBM
60.0%.
LUTH
83.3%.
Mean = 4.87
Std Dev = 0.778
N = 62
Rating for satisfaction with the artificial lighting in office
neutral 25.8% 21.4% 23.1%
satisfied 53.2% 67.3% 61.9%
Total 100.0% 100.0% 100.0%
(χ2
= 9.99, p = 0.076)
Mean = 4.70
Std Dev = 0.911
N = 98
a 6 cells (50.0%) have expected count less than 5. The minimum expected count is 1.16.
Remarks:
mean 4.70 and SD, 0.911 as shown in figure 8. 29. The distribution peaks for satisfaction towards artificial lighting in
both building types skew slightly to the right and about exactly on the same place.
Figure 8.15: Satisfaction rating towards artificial lighting in the office

Table 8.37: Quality of artificial lighting at working station
poor 5.0% 3.0% 1.3%
fair 5.6% 10.0% 7.3% 3.0% 4.2% 5.0%
adequate 38.8% 20.8% 25.0% 43.9% 33.3% 45.8% 35.6%
good 50.0% 62.5% 55.0% 46.3% 60.6% 45.8% 53.1%
excellent 5.6% 16.7% 5.0% 2.4% 4.2% 5.0%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
50.0%.
KOMTAR
41.4%.
MESINIAGA
79.2%.
TIMA
54.6%.
IBM
45.0%.
LUTH
45.8%.
Table 8.38: Quality of artificial lighting at lift lobby
poor 5.0% 0.6%
fair 4.2% 35.0% 19.5% 6.1% 16.7% 13.8%
adequate 44.4% 12.5% 15.0% 46.3% 33.3% 45.8% 34.4%
good 50.0% 62.5% 45.0% 34.1% 60.6% 37.5% 47.5%
excellent 5.6% 20.8% 3.8%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
55.6%.
KOMTAR
14.6%.
MESINIAGA
79.1%.
TIMA
54.5%.
IBM
LUTH
20.8%.
Table 8.39: Quality of artificial lighting at corridor/pathway
fair 16.7% 4.2% 25.0% 24.4% 3.0% 16.6% 15.0%
adequate 33.3% 20.8% 30.0% 43.9% 36.4% 54.2% 37.5%
good 44.4% 62.5% 45.0% 31.7% 60.6% 29.2% 45.0%
excellent 5.6% 12.5% 2.5%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
33.3%.
KOMTAR
MESINIAGA
70.8%.
TIMA
57.6%.
IBM
20.0%.
LUTH
12.6%.

Quality of artificial light at your workstation
poor 1.6% 1.0% 1.3%
fair 4.8% 5.1% 5.0%
adequate 27.4% 40.8% 35.6%
good 56.5% 51.0% 53.1%
excellent 9.7% 2.0% 5.0%
Total 100.0% 100.0% 100.0%
Mean = 3.68
Std Dev = 0.785
N = 62
Mean = 3.48
Std Dev = 0.677
N = 98
Quality of artificial light at lift lobby area
poor 1.6% 0.6%
fair 12.9% 14.3% 13.8%
adequate 22.6% 41.8% 34.4%
good 53.2% 43.9% 47.5%
excellent 9.7% 3.8%
Total 100.0% 100.0% 100.0%
Mean = 3.56
Std Dev = 0.898
N = 62
Mean = 3.30
Std Dev = 0.707
N = 98
Quality of artificial lighting at corridor or pathway
fair 14.5% 15.3% 15.0%
adequate 27.4% 43.9% 37.5%
good 51.6% 40.8% 45.0%
excellent 6.5% 2.5%
Total 100.0% 100.0% 100.0%
Mean = 3.50
Std Dev = 0.825
N = 62
Mean = 3.26
Std Dev = 0.708
N = 98
Figure 8.16: Histogram and normal curve for artificial lighting rating at several building
areas

8.6 Noise Level in Building
Users’ perceptions of the indoor noise level condition and their satisfaction level with them
are presented in this section. Several rating scales were used in the survey to evaluate noise
level condition in several areas in the building. Overall condition and satisfaction towards
noise level were also rated by the users.
Overall noise level in building
Table 8.40 shows the rating frequency for overall noise level in building. Figure 8.17 shows
the histogram and normal curve for the collective distribution by type. The statistics indicate
that all buildings have about the same rating for noise level rated by the respondents in those
buildings. However, about 12% consider the noise level to be slightly noisy in LUTH. This
might be due to the number of colleagues working in the same area in LUTH offices which
were found to be the highest among all buildings (see 6.3.3; table 6.5).
Collectively, the highest rating falls into ‘slightly quiet’ in bioclimatic building type and ‘just
nice’ in conventional type, at 43.5% and 64.3% respectively. The rating distribution varies
from ‘too quiet’ to ‘slightly noisy’ for bioclimatic buildings whereas in conventional
buildings it varies from ‘much too quiet’ to ‘too noisy’. There is no clear advantage either in
bioclimatic or conventional buildings in noise level criteria but the histogram and normal
curve shows some difference for both types (see figure 8.17).
Satisfaction of the noise level in office building
Table 8.41 shows the users’ satisfaction towards the noise level in their building. Figure 8.18
pictures the histogram and normal curve for each type collectively. The statistics indicate
that satisfaction towards the noise level in bioclimatic building is highly rated by the
buildings. This outcome gives an indication that the respondents in bioclimatic building
perceived a better noise level condition than in conventional ones. The highest rate is for the
‘satisfied’ category in bioclimatic building type and ‘neutral’ in conventional type at 71.0%
and 49.0% respectively. The rating distribution varies from ‘highly satisfied’ to ‘dissatisfied’
for both bioclimatic and conventional buildings types but the curve peak describing users in
bioclimatic building showed them to be more satisfied than those in conventional buildings
(see figure 8.18).

Discussion:
It was anticipated that bioclimatic buildings might be exposed to the outside noise due to
open-able windows available in most of the office areas. The rating for both perceptions
(noise condition and satisfaction) for every individual building is comparatively small. There
is no clear disadvantage to having those open-able windows around the office areas. Despite
that, based on the collective measure (see figure 8.17 and 8.18), it shows a very clear
indication that bioclimatic building has a better rating compared to the rating obtained from
conventional buildings in term of noise level condition. The users’ satisfaction toward the
condition also describes similar results. The chi-square value and asymptotic significance 2-
sided for the cross tabulation is (χ2
= 22.12, p = 0.000). This clearly explains that the
bioclimatic type have better rating than conventional type in term of users’ satisfaction
towards the noise level in the building (see histogram figure 8.18). It is statistically
significant which means it does not happen by chance as p < 0.05.
As mentioned in the previous section (Chapter 7) the noise level measurement in all
buildings is quite high compared to most requirements and standards for office buildings.
Although the average readings were about 3 to 7 dB above the comfort level (60 – 70 db),
the occupants (most of them) still consider the condition in the office area to be just nice or
slightly quiet (see table 8.40 and figure 8.17). Furthermore, most of them perceived the
condition as neutral and satisfied (see table 8.41 and figure 8.18).
Tables 8.42 to 8.44 present the perception statistics of subjects towards the quality of noise
in building in several areas such as at the work station, in the lift lobby and corridor. The
statistics show that bioclimatic buildings is highly rated by the respondent in those areas than
the rating obtained in conventional ones except for working station areas (see also figure
8.19).

Table 8.40: Rating frequency for overall noise level in the office
too noisy 2.4% 4.2% 1.3%
slightly noisy 8.3% 9.8% 6.1% 12.5% 6.9%
just nice 27.8% 45.8% 40.0% 65.9% 63.6% 62.5% 54.4%
slightly quiet 55.6% 37.6% 40.0% 17.0% 24.2% 16.7% 28.8%
too quiet 16.7% 8.3% 20.0% 4.9% 3.0% 4.2% 8.1%
much too quiet 3.0% 0.6%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
Slightly quite to much too quite ratings higher than
slightly noisy to much too noisy ratings by 72.3%.
KOMTAR
MESINIAGA
TIMA
IBM
LUTH
Mean = 4.69
Std Dev = 0.759
N = 62
Rating for overall noise level in building
too noisy 2.0% 1.3%
slightly noisy 3.2% 9.2% 6.9%
just nice 38.7% 64.3% 54.4%
slightly quiet 43.5% 19.4% 28.8%
too quiet 14.5% 4.1% 8.1%
much too quiet 1.0% 0.6%
Total 100.0% 100.0% 100.0%
Mean = 4.17
Std Dev = 0.774
N = 98
Remarks:
The curve peak for conventional building type skew slightly to the right and for bioclimatic building type; the peak
skew to the right slightly further than that of conventional ones. The bioclimatic building type has rating mean 4.69
and SD, 0.759 whereas conventional building type has rating mean 4.17 and SD, 0.774.
Figure 8.17: Noise level rating in the office

Table 8.41: Rating frequency for satisfaction towards noise condition in office
dissatisfied 5.6% 8.3% 2.4% 3.0% 8.3% 4.4%
neutral 16.6% 20.8% 5.0% 53.7% 39.4% 54.2% 35.6%
satisfied 66.7% 54.3% 95.0% 34.1% 48.5% 29.2% 50.6%
very satisfied 11.1% 8.3% 9.8% 6.1% 8.3% 7.5%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
72.2%.
KOMTAR
41.5%.
MESINIAGA
62.5%.
TIMA
54.6%.
IBM
95.0%.
LUTH
29.2%.
Mean = 4.89
Std Dev = 0.727
N = 62
Rating for satisfaction towards the noise level in the office
neutral 14.5% 49.0% 35.6%
satisfied 71.0% 37.8% 50.6%
Total 100.0% 100.0% 100.0%
(χ2
= 22.12, p = 0.000)
Mean = 4.53
Std Dev = 0.749
N = 98
a 5 cells (50.0%) have expected count less than 5. The minimum expected count is 1.16.
Remarks:
The curve peak for conventional building type skew to the right further than that of bioclimatic building types as
shown in figure 8. 33. The bioclimatic building type has rating mean 4.89 and SD, 0.727 whereas conventional
building type has rating mean 4.53 and SD, 0.749
Figure 8.18: Satisfaction rating towards noise level in the office

Table 8.42: Quality of the noise level at working station
poor 3.0% 0.6%
fair 5.6% 7.3% 3.0% 12.5% 5.0%
adequate 27.8% 8.3% 45.0% 63.4% 21.2% 62.5% 40.0%
good 66.6% 66.7% 50.0% 24.4% 51.5% 20.8% 43.8%
excellent 25.0% 5.0% 4.9% 21.2% 4.2% 10.6%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
61.1%.
KOMTAR
22.0%.
MESINIAGA
91.7%.
TIMA
66.7%.
IBM
55.0%.
LUTH
12.5%.
Table 8.43: Quality of the noise level at lift lobby
poor 3.0% 0.6%
fair 5.6% 12.2% 3.0% 4.2% 5.0%
adequate 33.3% 12.5% 50.0% 63.4% 30.3% 70.8% 45.0%
good 61.1% 62.5% 50.0% 24.4% 63.6% 25.0% 45.6%
excellent 25.0% 3.8%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
55.5%.
KOMTAR
12.2%.
MESINIAGA
87.5%.
TIMA
57.6%.
IBM
50.0%.
LUTH
20.8%.
Table 8.44: Quality of the noise level at corridor
fair 4.2% 12.2% 6.1% 8.3% 6.3%
adequate 38.9% 20.8% 45.0% 65.9% 42.4% 75.0% 50.0%
good 61.1% 54.2% 50.0% 19.5% 51.5% 16.7% 39.4%
excellent 20.8% 5.0% 2.4% 4.4%
TOTAL 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0%
UMNO
61.1%.
KOMTAR
MESINIAGA
70.8%.
TIMA
45.4%.
IBM
55.0%.
LUTH

Quality of noise condition at working station
poor 1.0% 0.6%
fair 1.6% 7.1% 5.0%
adequate 25.8% 49.0% 40.0%
good 61.3% 32.7% 43.8%
excellent 11.3% 10.2% 10.6%
Total 100.0% 100.0% 100.0%
Mean = 3.82
Std Dev = 0.641
N = 62
Mean = 3.44
Std Dev = 0.813
N = 98
Quality of noise condition at the lift lobby area
poor 1.0% 0.6%
fair 1.6% 7.1% 5.0%
adequate 30.6% 54.1% 45.0%
good 58.1% 37.8% 45.6%
excellent 9.7% 3.8%
Total 100.0% 100.0% 100.0%
Mean = 3.76
Std Dev = 0.645
N = 62
Mean = 3.29
Std Dev = 0.642
N = 98
Quality of noise condition at corridor/pathway
fair 1.6% 9.2% 6.3%
adequate 33.9% 60.2% 50.0%
good 54.8% 29.6% 39.4%
excellent 9.7% 1.0% 4.4%
Total 100.0% 100.0% 100.0%
Mean = 3.73
Std Dev = 0.657
N = 62
Mean = 3.22
Std Dev = 0.618
N = 98
Figure 8.19: Histogram and normal curve for quality of noise condition rating at several
building areas

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