SCHOOL OF ARCHITECTURE, BUILDING & DESIGN
Centre for Modern Architecture Studies in Southeast Asia (MASSA)
Bachelor of Science (Honours) (Architecture)
BUILDING SCIENCE 1 (ARC 2412)
AUGUST 2013 INTAKE
__________________________________________________________________________________
Project 1
Human Perception of Comfort Level
Thermal comfort (British Standard BS EN ISO 7730)
‘that condition of mind which expresses satisfaction with the thermal
environment.’
Name
Hong Si Mun
Lau Hao Shun
KhooChee Mei
Kueh Yen Chiew
Hans Hosea Gonza
PreshantRasu
Student ID
0312643
1101G11896
0303125
0312706
0311772
0312813
CONTENT
1.0 Objective ------------------------------------------------------------------------------------1.1 General Procedure
2.0 Introduction
--------------------------------------------------------------------------2.1 Human thermal comfort and factors affected
2.2 Introduction of site
2.3 Macroclimate
2.4 Microclimatic
2.5 Human Activity
3.0 Methodology
---------------------------------------------------------------------------3.1 Building Analysis
3.2 Building Material used in the space
3.3 Tool used to record the data
4.0 Analysis of report ---------------------------------------------------------------------------4.1 Analysis of air temperature and relative humidity
4.2 Bioclimatic chart
4.3 Sun path in Cheras
4.4 Solar radiation
4.5 Wind rose and ventilation
4.6 Heat transfer and human activity
5.0 Discussion -------------------------------------------------------------------------------------6.0 Conclusion -------------------------------------------------------------------------------------7.0 Reference --------------------------------------------------------------------------------------
1.0 OBJECTIVE
The objective of this project is to define thermal comfort in relation to people and space, heat
transfer between physical systems while observing the environment around us. We are to focus
into the building types and quality of space throughout this project. Besides that, the factors that
affect the thermal comfort in a specific space also one of the aspect that we experiment in this
project.
1.1 General Procedure
In this project, we were given a task to measure and find out the range of air temperature, relative
humidity, sun path and air velocity that is within the comfort level. We are to explain the reasons
by analyzing the building and site in context.
The period that we start to monitor the temperature in a room at our chosen site are from 10 pm,
Friday evening (5th September 2013) to 6 am, on the following Sunday morning (7th September
2013).
All the results, analysis, figures and graphs are shown in the following pages. All these results
recorded are based on the factors of human thermal comfort to the building.
2.0 INTRODUCTION
2.1 Human thermal comfort and factors affected
Human thermal comfort is defined by ASHRAE standard 55 as the condition of mind that
expresses satisfaction with the surrounding environment.
Thermal comfort divided into 2 categories: environment and personal. The sub-categories are
shown in the following figure 2.1. Both of the categories’ data is measureable as in MS 1525 by
using a specific tool, data logger.
Environment Factors




Sun path
Air temperature
Relative humidity
Wind speed
Personal Factors
 Clothing insulation
 Metabolic rate
Figure 2.1.1
According to the official Malaysian Standard website (http://www.msonline.gov.my/default.php)
the indoor environment design of an air-conditioned space for suitable thermal comfort cooling
should be as follows:
Figure 2.1.2 Indoor Environment Recommended
Dry bulb temperature: 23°C – 26°C
Maximum dry bulb temperature: 22°C
Relative humidity: 55 % – 70%
Air movement: 0.15 m/s – 0.50 m/s
Maximum air movement: 0.7 m/s
2.2 Introduction of site
The selected case study was conducted in a double storey residential house located in 27, Jalan
Mutiara 3, Taman Mutiara, Cheras, 56000, Kuala Lumpur, Malaysia.
The period selected for the data collection was on 5th September to 7th September 2013. This
experiment is to get a variation of measurement by using data logger. The measurement noted
was in terms of the air temperature and relative humidity for indoor and outdoor environment.
The case study selected was residential terrace house. It was surrounded by terrace houses in 3
sides and facing the garden. There is a highway, Jalan Cheras located around 20 m away from the
building. The full details of the building are shown in the site plan below.
Figure 2.2.1 Site Plan
2.3 Macroclimate
Malaysia is located in Southeastern Asia (230 N, 112 30 E), divided into east and west Malaysia.
The case study we did is located in the west coast of Peninsular Malaysia. Specifically, Taman
Mutiara, Cheras is located at the east side of Kuala Lumpur.
Air temperature
The climate of west coast Peninsular Malaysia is uniform throughout the whole year. The average
lowest temperature is 23° C in the month of January. The average highest temperature in a year is
34°C in the month of March. This can be explained with the direction of the sun path which in the
month of March, the sun light penetrates directly on the equator.
Relative humidity
The relative humidity of the temperature is related to the air temperature. There is a clear
relationship between air temperature and relative humidity. The higher the air temperature, the
faster the air particles evaporates, so the relative humidity should be low.
Sun path
Being a maritime country close to the equator, Malaysia naturally has abundant sunshine and thus
solar radiation. On the average, Malaysia receives about 6 hours of sunshine per day.
Wind speed
The wind speed over Peninsular is generally light and variable. However, some uniform periodic
changes in the wind flow patterns can be distinguished, for example the southwest monsoon. It is
usually established in the later half of May or early June and ends in September. The prevailing
wind flow is generally southwesterly and light, below 15 knots.
Rainfall
Over the west coast of the Peninsula with the exception of the southwest coastal area, the monthly
rainfall pattern shows the maximum rainfall is within the periods of October – November (wet
season).The dry season in month of September create a great difference of temperature that cause
less average rain fall compare to other month. The average rainfall in September is approximately
210mm. (Figure 2.3.1)
Figure 2.3.1 Average Rainfall
2.4 Microclimate
Air temperature
According to the world weather online, the average weather in Kuala Lumpur is hot and humid.
Temperature in Kuala Lumpur varies a little from season to season. The air temperature on 5th to
7th September fluctuates due to the sun path where the difference of range if 6°C. The details of the
air temperature is shown in (4.0 Methodology --- 4.1 Analysis of air temperature and relative
humidity)
Relative humidity
Since Malaysia is close to the equator, therefore, Cheras, Kuala Lumpur basically enjoys tropical
rainforest climate. There are essentially two seasons in Kuala Lumpur: dry season (May to
September) and a wet season (mid-November to March). Our data collection period fall on the
month of September where we expect our overall relative humidity is slightly lower than other
month.
Sun path
The building that our group selected is a residential terrace house where it is facing the north and
blocked on the east and west side. The sun path that we selected is on the 31st March where the
sun radiation penetrates directly on the equator.
Wind speed
For specific research on climate of Cheras, Kuala Lumpur in the month of September, the southwest monsoon continues to blow over western coastline bringing with heavy afternoon
thunderstorms.
2.4 Human Activity
Throughout the data recorded period, the metabolic rate and clothing insulation of the tenant also
recorded. The data is recorded based on the ASHRAE Standard 50 Appendix A and Appendix B.
On the data recorded period, there is maximum 3 people moving around the area and half of the
time there is no activity carried out in that area. The human activity of that space based on the
daily activity of the tenant. The detail activity is shown in the following figure.
The tenants moving around in this area are with short sleeve cotton shirt and shorts. These
clothing is categorized in summer clothing where the value estimate around 0.5 clo.
TIME
TV
TREADMILL
TELEPHONE
WINDOWS
LIGHTS
FAN
#PEOPLE
10pm
Off
Off
Off
Closed
On
Off
1
11pm
Off
Off
Off
Closed
Off
Off
0
12pm
Off
Off
Off
Closed
Off
Off
0
1am
Off
Off
Off
Closed
Off
Off
0
2am
Off
Off
Off
Closed
Off
Off
0
3am
Off
Off
Off
Closed
Off
Off
0
4am
Off
Off
Off
Closed
Off
Off
0
5am
Off
Off
Off
Closed
Off
Off
0
6am
Off
Off
Off
Closed
On
On
1
7am
Off
Off
Off
Open
On
On
2
8am
Off
Off
Off
Closed
Off
Off
0
9am
Off
Off
Off
Closed
Off
Off
0
10am
Off
Off
Off
Closed
Off
Off
0
11am
Off
Off
Off
Closed
Off
Off
0
12pm
Off
Off
Off
Closed
Off
Off
0
1pm
Off
Off
Off
Closed
Off
On
0
Thursday
Friday
2pm
Off
Off
Off
Open
Off
On
0
3pm
Off
Off
On
Open
Off
On
1
4pm
Off
Off
On
Open
Off
On
2
5pm
Off
Off
On
Open
Off
On
2
6pm
Off
Off
On
Open
Off
On
3
7pm
On
Off
On
Open
On
On
2
8pm
On
Off
On
Open
On
On
3
9pm
On
On
On
Open
On
On
2
10pm
On
On
On
Open
On
On
2
11pm
Off
Off
On
Closed
On
On
1
12am
Off
Off
Off
Closed
Off
Off
0
1am
Off
Off
Off
Closed
Off
Off
0
2am
Off
Off
Off
Closed
Off
Off
0
3am
Off
Off
Off
Closed
Off
Off
0
4am
Off
Off
Off
Closed
Off
Off
0
5am
Off
Off
Off
Closed
Off
Off
0
6am
Off
Off
Off
Closed
Off
Off
0
Saturday
Figure 2.4.1 Activity carried out in the data recorded area
3.0 Methodology
3.1 Building analysis
The case study selected is a terrace house located in Cheras, Kuala Lumpur, Malaysia.
Figure 3.1.1 First floor plan
Figure 3.1.2 Second floor plan
Figure 3.1.3 Living room floor plan
Figure 3.1.4 front elevation
Figure 3.1.5 side elevation
Figure 3.1.6 back elevation
Figure 3.1.7 section
Figure 3.1.8 Photo of the selected space
During the data collection period, only certain electrical appliances are switched on. We try to
control the condition of the space and experiment the basic factors of thermal comfort. Due to the
data logger is highly sensitive apparatus, it is placed in the middle point of the living room and 1 m
above the floor. This procedure is to confirm that there if minimal factors the reading error of the
data logger.
3.2 Building Materials used in the spac e
Building materials is one of the characteristic that should be considered in a building. The material
used may affects the thermal comfort of the building. The following material is used in the case
study building.
Sector in the space
Wall
Roof
Floor
Door
Window
Material
Masonry
Clay
Terrazzo
Wood
Glass
U-value(W/m²K)
0.28
0.62
0.22
0.64
1.60
U-value is a measure of heat loss in a building element. There is a clear relationship between Uvalue and the insulation properties of a building element. If the U-value is high, the thermal
performance of the building envelope is low. In the opposite way, the low U-value usually
indicates high levels of insulation.
3.3 Tool used to record the data
Figure 3.3.1 Image of data logger
The data logger was placed in the middle of the living room about 1m height from the floor, and
left on for the whole of 3 days. During the 3 days, the unit was left neither untouched nor amended.
Once the data recording was done, the unit was switched off, had its SD card removed and then
placed into the computer to upload the data to Microsoft Excel.
4.0 ANALYSIS OF REPORT
4.1 Analysis of air temperature and relative humidity
Based on the graph above, there is a clear line that outdoor temperature fluctuated frequently
while the indoor temperature remains stable.
The highest outdoor temperature is 30°C on 3 pm to 5 pm (6th September). The factor that changes
the outdoor temperature maybe because of the sun set where sunlight reflected on the roads and
causes temperature increases. The lowest temperature is 24°C on 1 am to 7 am (6th September).
The reason to support the reading is there is no sun radiation in 1am to 7 am where the
temperature supposes to be low. Temperature starts to increase from 7 am to 3 pm (6th
September) where there is solar radiation and finally reaches the highest temperature. The
temperature gradually decreases from 5 pm onwards where the sun starts to set. The difference of
temperature in outdoor environment is 6°C where the range is slightly larger than indoor
environment.
The overall graph for indoor temperature is slightly higher than outdoor temperature but the
readings remain stable throughout the date collection period. The highest temperature is 29.5°C
on 5pm to 6 pm and 9 pm to 10 pm (6th September) while the lowest temperature is 28°C on 8am
(6th September). The difference of temperature is 1.5°C.
Besides that, the relative humidity of the environment is based on the change of temperature.
Based on the graph plotted, the outdoor relative humidity shows a drastic change in the
percentage rate. The highest relative humidity remains constant for outdoor environment where
the reading is 94% from 12 am to 7 am (6th September). The lowest relative humidity remains at
70% from 2 pm to 5 pm (6th September). There is a great increase in humidity on 1 am to 3 am and
fluctuate dramatically until 5 am (7th September) where the weather is partially cloudy. The
difference of relative humidity of outdoor environment is 24% while the mean is approximately
85.8%.
On the other hand, the indoor relative humidity shows more constant graph reading. The highest
reading for indoor environment is 72% on 8 am (6th September). The lowest reading is 66% on
12am (7th September). The difference of percentage is only 6% and the mean is around 61.1%.
From the analysis of both of the data, the range of relative humidity for outdoor temperature is
higher than indoor temperature. This shows that the factors of the building control the relative
humidity of the specific space which makes the readings constant.
Furthermore, from the analysis of the graph, it shows a relationship between air temperature and
relative humidity. When the air temperature of certain environment is high, the relative humidity
reading is low and vice versa. The second relationship that we get from the graph is the indoor
temperature is higher than outdoor temperature due to human activity. Based on the human
activity table listed above (figure 2.3), the highest temperature of indoor environment is on 5 pm
to 6 pm (6th September) where there is 2 to 3 people moving in that space. The telephone, fan and
window are on in that particular time slot. While for time slot 9 pm to 10 pm, the air temperature
should decreases due to the night but the temperature still remain high. This is because all the
electrical appliances are switched on and there is exercise carried on. The person will radiate heat
due to metabolic rate and indirectly causes the temperature of indoor environment to increase.
4.2 Bioclimatic Chart
From the data collected from the data logger. The mean relative air humidity was calculated as
61.1% and the mean temperature was 28.8°C for the period of data collection. We used this
information to plot on the bioclimatic chart as shown.
The chart shows that our space is within the comfort zone. This is clearly due to the proper cross
ventilation achieved by proper placement of windows and doors throughout the entire building
and shading that prevents direct sunlight into the room. Some of the major sources of heat are the
electrical appliances and human metabolic rate.
4.3 Sun path in Cheras
Figure 4.3.1 Horizontal sun path diagram on Cheras
Located at 3.15°N latitude, at the equator of the Earth, Cheras housing area have a variation of sun
path at different time of the year. The area received adequate sun light the whole year.
The area will experience least thermal intensity on March and September. The thermal intensity is
moderate on September and December. Highest thermal intensity is experienced during June.
These area is not shaded by any building due to it is housing development area.
Sun-shadow in Investigated Room Unit
On 5th September 2013, the position of Sun at 9a.m. is at 28° altitude and N 70 ° E azimuth. Shade
is mainly available at the back of the building. The length of shadow casted by the buildings in the
housing area is the same as they are of the same type.
Zooming into the house unit, the window and door openings are mostly located at the East and
West of the building. The East side of the building is shaded with the balcony while the west side
of the building is shaded by the overhang of roof which is extended to the end of the building.
Figure 4.3.2 Sun and shadow on 5th September 2013 at 9am
Figure 4.33 Shading in the site section on 5th September 2013 at 9am
Figure 4.3.4 Shading in the floor plan on
5th September 2013 at 9am
Figure 4.3.5 Shading in the fright
elevation on 5th September 2013 at 9am
Direct sunbeam affect the East and west side of the building. It does not hit into the
building as the opening is shaded by the balcony at the east and a large overhang at the
back of the building. The side elevation is longer as it is not facing the direct sun beam
where there are no shadow is casted on that side of elevation as shown in figure 4.35.
Figure 4.3.6 Sun and shadow on 5th September 2013 at 1pm
Figure 4.3.7 Shading in the site section on 5th September 2013 at 1pm
Figure 4.3.8 shading in the floor plan on
5th September 2013 at 1pm
Figure 4.3.9 shading in the right
elevation
on 5th September 2013 at 1pm
On 5th September 2013, the position of sun at 1pm is of 78°altitude and N 12 ° E azimuth
affect the North side of the building. Sun beam is not directed to the living room. The
projection of balcony and overhang provided shades to the first and ground floor to the
building. The selected room is not affected as it was on the ground floor.
Figure 4.3.10 Sun and shadow on 5th September 2013 at 5pm
Figure 4.3.11 Shading in the site section on 5th September 2013 at 5pm
Figure 4.3.12 Shading in the floor plan
on 5th September 2013 at 1pm
Figure 4.3.13 Shading in the
right elevation on 5th
September 2013 at 1pm
On 5th September 2013, the position of sun at 5pm is of 32° altitude and N 10 ° E azimuth
affect the West side of the building. The living room is shaded as it is on the East side of the
building. The roof and overhang is used to shade the West of the building.
4.4 Solar radiation
The intensity of solar radiation in hot and humid country as Malaysia is high and uniform
throughout the year.
Solar penetration is depend on the weather of that day as whether it is clear sky portion or
cloudy portion or direct sunlight.
The house selected for this project is located at Cheras and it is a double storey house. The
house is facing east; the surfaces that are exposed to the solar radiation are roof, front
elevation and back elevation. The balcony on the left side of the house; and large overhang
on the right side of the house from the figure showing that it receives lesser of solar
radiation with this design.
Figure 4.4.1 Heat distributions throughout the building.
The room selected for this project is the one on the bottom left. As there is a balcony in front
of the room, there is no direct sunlight shines into the room. The surface that receive direct
sunlight are roof, front façade and back façade, therefore heat accumulate mostly on roof
area. The room is located at the ground floor and therefore the effect of solar radiation of
the room is not prominent.
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Figure 4.4.2 Solar ray at 9.00 am, 5th of September
As the balcony of the house on the front elevation blocked most of the solar ray at that time,
the temperature room chosen for the case study is within thermal comfort.
Figure 4.4.3 Solar ray at 1.00 pm, 5th of September
At 1pm, the sun is at the top and the solar ray shines directly on the roof of the house.
However, due to the balcony at the front acted as overhang, the wall of the room is still
shaded and no direct sunlight is shining on the room.
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Figure 4.4.4 Solar ray at 5.00 pm, 5th of September
At 5pm, the wall of the room is still being shaded as the house at the left side is blocking the
sunlight. There are no direct sunlight at all.
4.5 Wind Rose and Ventilation
Figure 4.5.1 Annual wind rose for Cheras neighbourhood
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The Cheras housing area in Kuala Lumpur will experience wind from all side of the direction.
The significant wind speed will be from South East direction which reaches as high as
11m/s of wind speed.
Figure 4.5.2 Wind rose for Cheras neighbourhood from 5-7th Sept 2013
Cheras residence area experience Southwest Monsoon in the month of June - September
with milder wind coming from south west. This season usually accompanied with light
winds, clear mornings, thunderstorms in afternoon.
The wind rose above shows the date and direction of the wind in Cheras area. The highest
frequency of the wind is from south-east which occupies 63% of the graph. The south-east
wind had the fastest wind speed which is 20-30 km/h and it is significant ventilation for a
building.
The building that we selected is facing east and park which crowded with plant and
vegetation despite 3 façade of it being obstructed by the two storey houses. The south-east
wind will go through the main window and door towards the space. There is a significant
wind from the south-east, so the ventilation quality of the building does improve. For the
front façade of the building, there is 63% of wind coming in and the wind speed is 20-30
km/h where the less significant wind is from south-west.
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Figure 4.5.3 front elevation
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From the analysis of site plan, there is a small portion of forest in the south-west of the site
plan. The landscape of the small forest is slightly higher than the residential area and it is
around 500 m away from the building. The south-west wind occurs most probably because
of the present of the forest and carries the wind from high area to low area.
Figure 4.5.4 site plan
The only ventilation in the living room is the main window and door. Through the analysis
of the building, the wind is coming in through the window from the direction of south-east.
The wind speed and wind percentage of front façade compare to back façade is higher.
Therefore, the ventilation of whole building is from front to back.
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4.6 Heat Transfer and Human Activity
Heat transfer is a discipline of the exchange of thermal energy and heat between physical
systems. Heat gain in the living room from external sources and internal activities. The
external sources are through solar radiation from the window and internal activities are
from the heat radiated by the electrical appliances and human metabolic rate.
The major external source of heat is from the sun radiation. The extreme heat gain is from
the day especially in the afternoon. The sun penetrates through the air, hit on the street and
reflects into the building. The temperature of indoor will increase due to the significant sun
radiation. The minor heat from external environment is the heat radiation of the vehicles.
This is a minimal heat gain for external environment compare to sun radiation.
Figure 4.6.1 Cross ventilation throughout investigated room unit to the end of the building
The wind is travel throughout the investigated unit, the living room to the entire building.
The cross ventilation is achieved by proper placement of windows and doors throughout
the entire building. The major heat gain in the living room is from electrical appliances and
human metabolic rate.
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DISSCUSSION
After the analysis is completed, we understand that the existing conditions perform a
thermal comfort to human activity. But, there is a few ways to improve more on the quality
of the space. The improvement of the elements is to demonstrate a better quality of the
space regards to MS1525.
The first improvement is to consider the U-value of the materials. The material that we want
to emphasis on is the glass used in the window. The glass suggested maybe the double
glazed glass where there is air space between the panels. The U-value is lower which means
the level of insulation is higher.
The second suggestion is to enlarge and add more openings. The openings for existing
condition are suitable for human activity. To improve the quality of ventilation, we will
suggest a bigger opening in the front façade. Another ways is to have a ridge vent on the
roof so that the heat and air can move in various directions.
The window style also one of the factor that will affect the ventilation. As the original
window is casement window, center opening that will bring 70% of wind into the building.
We suggest using casement opening, directional opening or opening louvies that will bring
90% of wind into the space.
The last suggestion is the shading device. The original building uses balcony as a shading
device as it is consider as horizontal shading. For building that faces east and west, the
better solution for shading device is to use egg-crate style as shading. The inward and deep
opening can prevent the solar heat and penetration throughout the space.
CONCLUSION
In conclusion, the space is within the thermal comfort range. Although the external
condition of downpour and solar radiation affects the investigated room unit, but according
to MS 1525, vegetation is helping to cool the surrounding. The existence of the plant at the
site is good heat diffusion.
The presence of difference of temperature inside and outside is due to the night flush
cooling where the heat is absorb and being released at night to cool the interior. Basic
building design as cross ventilation is provided with the placement of the front to the back
of the building which cools the interior. Heat gain in the building is mainly due to the human
activities.
Shading devices is efficient with the balcony placement at the front elevation which shaded
the investigated room from unwanted solar radiation. The orientation of the building with
the longer side is facing North and South is helping to the shade the room alongside the
building where there are no window placement but only having a window for toilet to allow
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ventilation which will bring the unwanted smell out of the toilet. To avoid the direct solar
radiation from coming in, the elevation of the East and West is shorter. To further enhance
the building from receiving too much of unwanted solar radiation, the balcony and larger
overhang and roof are keys to enhance the comfort zone of for the user in the selected room.
Furthermore, the wind speed for the space is considered strong in certain direction. The
strong wind is from south-east and it faces the main window in the front facade. The
ventilation quality within this space is good and it reaches the requirement of thermal
comfort space for human activity.
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Reference
Website
ASHRAE official website
https://www.ashrae.org/resources--publications/bookstore/standard-55
Malaysian standard official website
http://www.msonline.gov.my/default.php
Thermal comfort
http://en.wikipedia.org/wiki/Thermal_comfort
Books
1. Ken Yeang (2008), Ecodesign, Amanual for ecological design, Great Britain by John
Wiley & Sons, Inc.
2. Krisham A., Baker N, Yannas S, Szokolay S.V., Climate responsive architecture, A
design handbook for energy efficient building by Tata McGraw Hill.
3. Baker N., Steemers K., Energy & environment in architecture, a technical design
guide, London & New York by Taylor & Francis.
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