building science 1 final

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Contents 1. Summary 2. Introduction 2.1. General Purpose of Study 2.2. Limitation of Study 2.3. Report Preview 2.4. Diagram and Pictures of Site 3. Methodology 3.1. Equipments 3.2. Factors Affecting Thermal Performance of the Building 3.3. Scaled Drawings 4. Results and Findings 4.1. Temperature and Relative Humidity VS Time Graph 4.2. Bioclimatic Chart 5. Analysis on Thermal Performances 5.1. Site Context 5.1.1. Macro-climate Site Context 5.1.2. Micro-climate Site Context 5.2. Solar Radiation 5.3. Air Movement and Velocities 5.3.1. Wind 5.3.2. Ventilation 5.4. Materials 1 5.4.1. Low-E Glass 5.4.2. Roof Tiles 5.4.3. Brick Wall 5.4.4. Gypsum Board 5.4.5. Aluminum Frame 6. Conclusion 7. References 8. Appendix 2 3 - 10 11 - 20 21 - 25 26 - 46 47 48 49 - 51

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Page 1: Building science 1 final

Contents

1. Summary 2. Introduction

! ! 2.1.! General Purpose of Study! ! 2.2.! Limitation of Study! ! 2.3.! Report Preview! ! 2.4.! Diagram and Pictures of Site

3. Methodology ! ! 3.1.! Equipments ! ! 3.2.! Factors Affecting Thermal Performance of the Building ! ! 3.3.! Scaled Drawings

4. Results and Findings ! ! 4.1.! Temperature and Relative Humidity VS Time Graph ! ! 4.2.! Bioclimatic Chart

5. Analysis on Thermal Performances ! ! 5.1.! Site Context ! ! ! 5.1.1.!Macro-climate Site Context! ! ! 5.1.2.!Micro-climate Site Context! ! 5.2.! Solar Radiation! ! 5.3.! Air Movement and Velocities ! ! ! 5.3.1.!Wind! ! ! 5.3.2.!Ventilation! ! 5.4.! Materials 1! ! ! 5.4.1.! Low-E Glass! ! ! 5.4.2.!Roof Tiles! ! ! 5.4.3.!Brick Wall! ! ! 5.4.4.!Gypsum Board! ! ! 5.4.5. Aluminum Frame

6. Conclusion 7. References 8. Appendix

23 - 10

11 - 20

21 - 25

26 - 46

4748

49 - 51

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1. Summary

! The aim of the project is to create an understanding of the principles of heat transfer

in relation to the buildings and the people that use them. We also find out what thermal

comfort is and what the factors that affect it are. This study also tests our understanding of

how accurate the comfort zone can be when applying it to real life experiences.

! The project included choosing a site to study. Then we were given a Hydro-

Thermometer to measure the temperature and humidity in the site. The study was done

over three days and data was logged at hourly intervals. In our case we chose Siow Yee

Sinʼs room as the site and we did the data logging on from the 19th of April to the 22nd of

April. Aside from the data logger, we had to note all relevant information that would affect

heat transfer or temperature in the site. This included building materials, shading devices,

ventilation, sun paths and site contexts studies.

! After data collecting, the results were tabulated and a graph was generated. Other

resources were also collected such as outdoor temperature, humidity, wind path and

speed. These were then compared with each other to make sense of all the results. A full

analysis on factors affecting the thermal performance of the building was done. Using

resources from lecture materials, online sources and our pooled knowledge about the

subject, we concluded that the site does not comply to the MS1525ʼs definition of a

comfortable zone.

! However based on personal experience and further analysis of the building, we

found that thermal comfort was not a fixed value. Thermal comfort was achieved by its

users when in the building and certain factors were outlined as to why this was possible.

This also proves that thermal comfort varies from personal preferences by the individual.

A good example of the outside forces that made the building more comfortable is

ventilation, as the building was well ventilated at all times.2

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2. Introduction

2.1. General Purpose of the Study

! The project Human Perception of Comfort Level was conducted due to a few

purposes. The definition of ʻthermal comfortʼ is the condition of the mind that expresses the

satisfaction with the thermal environment. Thus, describing a personʼs psychological state

of mind and is usually referred to in terms of whether someone is feeling too hot or too

cold. It is also normally affected by the factors such as air temperature, radiant

temperature, relative humidity, air velocity, activity and clothing. The purposes of this

project is to identify and define the principles of heat transfer in relation to building and

people, to understand what is thermal comfort and discuss factors relating to thermal

comfort and to analyze the effects of thermal comfort factors in a person and in a space.

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2.2. Limitations of Study

Limitations of Study is the problems and apparent flaws the arise during the course of the

experiment that affects the study which cannot be avoided due to the lack of time and

resources that has been given to execute this study. Below are the limitations faced by our

group during the program of study.

1. Inaccurate External Temperature and Relative Humidity Data

There are a few limitations that had to be considered about when having to perform the

analysis. The first being the usage of inaccurate data of the external temperature and

relative humidity. Our group had utilized the temperature and relative humidity data of

Selangor, which indicates the data is more general and not concentrated within the site.

This limitation is crucial to be pointed out because it is used to compare the external and

internal temperature and relative humidity and to identify the comfort zone using these

datas.

2. Power Failure of the Data Logger

Other than that, our group had problems collecting data for the last 12 hours of the

experiment because the Data Logger ran out of power. Therefore, we are lacking the full

data of the experiment. This creates difficulties achieving a more accurate result in

identifying thermal comfort zone for the site.

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3. Inactivity of Space

The space of the experiment was also a limit as it is remained vacant during the course of

the experiment. This causes inactivity which creates a consistent data being recorded.

Compared to a space that is used for the course of the experiment, the data will be

affected by the factors including number of occupants, wind speed, windows that are

opened and humidity of the space.

4. Placement of Data Logger

Another limitation of our experiment is that the Data Logger was placed on a table near to

a curtain covered window which is never opened during the course of the experiment. This

is considered a limitation because of the fact that the Data Logger is exposed easily and

directly to the sun even with a curtain covering a window.

5. Limitation of Time

Our group are limited to perform the experiment in a 3 day period which during the length

of time, had a couple of problems with the Data Logger. The limited time also is caused by

the fact that the Data Logger needs to be shared among many groups in the course,

therefore, having a specified time of experiment meant every group will have equal

opportunities using the Data Logger. However with only limited time length, the data that

we recorded is not a direct representation of the actual climate throughout the year.

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2.3. Report Preview

! Before conducting the full analysis of the house, a preview of the report was

gradually made out. The predicted temperature of the room was around 30 degrees

Celsius and a 70% of relative humidity. The room would have a full sunlight exposure in

the mornings and getting slightly dimmer in the evening as the sun path goes. It is also

expected to have a regular wind exposure giving the outdoors some slight breeze and a

good ventilation as the room consists of three relatively large windows. The materials of

the house also aids in achieving thermal comfort as low-e glass and wooden deck

floorings are used. The overhang of the rood also provides a good shading system for the

room.

! As for site context, on both sides of the windows are shaded with tall trees with big

foliages. It covers up a lot of the sunlight and absorbs a relative amount of heat giving the

surroundings a cooling effect.

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2.4. Diagrams and Pictures of the Site

! The chosen site is a double story bungalow that is located at Jalan Sungai

Beranang, 32/52, Bukit Rimau, Shah Alam. It occupies an accumulated build up amount of

977 m². The analysis was conducted in one of the bedrooms on the top floor of the house.

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Key Plan(NTS)

Site : 41, Jalan Sungai Beranang, 32/52, Sri Suria, Bukit Rimau,

Selangor

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Front Elevation of the House

Side Elevation of the House

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Exterior of Studied Space

Interior of Studied Space

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Site Context showing the foliages around the study space

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3. Methodology

3.1. Equipment(s)

Data Logger

! For the study, we used a Hydro-Thermometer to measure the indoor temperature

(C) and relative humidity (RH). A Hydro-Thermometer is capable of recording logs of

measured data at specified time intervals. For this study we set the device up to record at

an interval of 3600seconds (1 hour) to create an hourly record of the indoor temperature

and relative humidity. The study will be done over three days. Therefore the machine will

be set up in the chosen room, at least 1 meter above ground to record data continuously

for the three days. The data recorded by the machine is stored within an SD card in a

spreadsheet format. This spreadsheet can be extracted from the card after the study to

access the recorded data.

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3.2. Factors Affecting Thermal Performances of the Building

The following are the factors the affects thermal performance of the building.

1. Building Form

! The building form can affect the thermal performance as it determines the size and

orientation of the exterior envelope exposed to the outdoor environment. The roof form can

also affect the thermal comfort of the space as the higher ceiling is, the better the

ventilation. The selected siteʼs house has a relatively high ceiling and the space is not

exposed to outdoor environment.

2. Building Orientation

! The building orientation can affect the building thermal performance by minimizing

the direct solar radiation into the buildingʼs envelop either by building openings or opaque

walls. The rooms is located at the top floor of the house and it has windows facing South

and East. It has minimal sunlight in the evenings.

3. Shading Devices

! The shading system of the house is the overhang of the roof and the thick foliages

that are available in the neighbor's yard.

4. Materials

! The room is made of timber strips flooring, plaster ceiling, clay roof tiles, low-e glass

and aluminum frames. These materials does not reflect the heat of the space and some

absorbs it.

5. Curtains

! The room has a double layer curtain covering each window. It has a layer of

transparent sheer curtains which blocks the first hit of sunlight and heat and after that the

thicker and heavier canvas layer does most of the heat blocking work.

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6. Occupants

! The chosen room is used as a bedroom of one person. Besides sleeping hours, the

room is rarely occupied. Occupation densities and types of activities affect the total heat

gain of a space. Humans give releases heat by the metabolism process to maintain a

constant body temperature.

3.3. Scaled Drawings

! The following are the scaled drawings of the studied building provided the owner of

the building.

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4. Results and Findings

4.1. Temperature and Relative Humidity VS Time Graph

! The graph shows the combined record of data (Humidity (RH) and Temperature (C))

that was measured on the 19th, 20th and 21st of April, 2013. During the three days, the

maximum indoor temperature recorded was 32.6 degrees Celsius, which was at 5:00PM

on the 20th of April 2013. The minimum indoor recorded temperature was 29.7 degrees

Celsius, which was between 6:00AM to 7:00AM on the 22nd of April 2013. The Maximum

temperature for the outdoor data was 35 degrees Celsius at 5:00PM on the 20th of April

2013. The Minimum temperature for the outdoor data was 26 degrees Celsius on all three

days at 5:00AM to 8:00AM, 9:00AM to 10:00AM, 1:00AM to 8:00AM on their respective

dates.

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! The maximum relative humidity from the indoor data indicates that it was 72.4% RH

at 11:00AM on the 20th of April 2013 and the minimum indoor relative humidity was 62.8%

which was at 4:00PM on the 20th of April 2013. For the Outdoor data, the maximum

recorded humidity level was 94% which was a constant event everyday around the early

hours of morning, around 1:00AM to 10:00AM. The minimum recorded humidity level for

the outdoor data was 63% RH at 5:00PM on 20th of April 2013.

! The average temperature and humidity for the indoor measurements are 31.0C and

68.4% RH. The average temperature and humidity for the outdoor data is 28.5C and 85%

RH.

! From the graph we can see that the patterns coincide with one another. When the

external humidity decreases the internal humidity decreases as well. This pattern can be

seen with the temperature graph lines as well.

! The internal temperature increases when the external temperature increases

because when it is hot outside, the house itself heats up along with the environment. The

degree of how much the outside temperature affect the indoor temperatures depends on

building materials, insulation and other heat-related properties that the house contains.

! The relative humidity for both inside and outside are related in the same way. If it is

dry outside, moisture moves towards the dryer air to balance it out. Therefore when there

is a dip in humidity outside, there will be a dip in the internal graph as well.

!

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! Aside from that, the temperature and humidity values are related. From the

behavior of all four lines on the graph we can conclude that the data is inversely

proportional to each other. Which means that when the temperature is high the relative

humidity decreases. This can be explained by the fact that it is dryer when it is hot outside

as all the moisture has evaporated away from the area. For example, on the 20th of April

2013 at 4:00PM to 5:00PM we see a record of the highest indoor temperature measured

and the lowest indoor humidity recorded. This relationship is described as inversely

proportional, i.e. the Temperature (C) value is inversely proportional to the Relative

humidity (%RH) or the Relative humidity (%RH) is inversely proportional the Temperature

(C).

! Looking closely at the graph, the minimum and maximum values indicate certain

events that happened in their respective time periods. During the times of maximum

humidity, the temperatures would be at their lowest point. This is due to the morning fog

which makes the air dense with moisture. It did not rain in that weekend, so this was the

only reason for the temperature dip and humidity peak.

! During the maximum temperature points, this would be around the afternoon. This

is because the chosen room is blocked by tall trees in the morning. So when the sun

reaches noon position, only then would its rays reach the area around the chosen room,

heating up the air and buildings there. The weather during the weekend was mostly cold in

the mornings and hot in the afternoons, this agrees with the results of the study.

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4.2. Bioclimatic Chart

! The bioclimatic chart shows the position of the comfort zone in a graph of

Temperature (C) versus Relative humidity (%RH). The average of the two values are taken

and plotted on it to see if the chosen room is in the comfort zone or not.

! The average values for indoor temperature and humidity was calculated to be 31.0

degrees Celsius and 68.4%RH respectively.

! As we can see from the graph, the point lies above the comfort point. While it is

within the comfortable humidity range, it is too hot to be in the actual comfort zone.

According the the MS1525 Standard, the comfort zone lies within the range of a

temperature of 23 to 26 degrees celsius, while the comfortable humidity range is around

55-70%RH.

!

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Too Dry

Wind Needed

Comfort ZoneShading Needed

Sultry

Unbereable Limit Of Light Work

0 10 20 30 40 50 60 70 80 90 100Relative Humidity

0

10

20

30

40

Temp/ c

Too Humid

Point of Average Humidity and Temperature

BIOCLIMATIC CHART

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! Despite the data poiting towards an uncomfortable place, personal experience of

the users of the space indicate that it is indeed a habitable place. They hardly need to

switch on air conditioning when in the space. This is most probably due to the good air

flow and ventilation. While the temperature is high,there is still a good breeze and air flow

that creates a comfortable environment.

! The ventilation would help clear the humidity from the room as we can see from the

low humidity average in the room. Therefore it can be concluded that comfort zone is a

value that is subjective to a personʼs own personal comfort zone and also the environment

that directly affects it.

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5. Analysis on Thermal Performances

5.1. Site Context

5.1.1. Macro-climate Site Context

! Bukit Rimau, Shah Alam is a place filled with nourished trees everywhere, lowering

the general temperature of the area as trees provides a sufficient amount of oxygen and

also gives very good shading.

! Bukit Rimau is also a little secluded from the city. It is a specific township as it is not

a very congested area where it is a town and it is not an access point to passerbys as it is

purely a residential area with a minimal amount of shoplots.

! Residences in this area uses the bicycle as one of the main transportation.

Especially when the destination is somewhere nearby in town. Thus again, minimizing the

use of cars.

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! The specific area of the site, Sri Suria consists an amount of around 50 bungalows.

The houses are all spatially laid out as there is at least a full three meters width in between

the houses. It also allows more space for air ventilation as air can come in from all four

sides of the house.

! As it is a guarded area and the houses inside are not packed, therefore the cars

traveling inside would be lesser, thus allowing the area to stay cooling with lesser heat

produced from vehicles.

! And according to this, the car amount in the area would be very little, hence lowering

the air pollution of the area and the temperature would not be risen, maintaining the area a

cool condition.

! Within Sri Suria, there is also a small lake which helps in cooling down the overall

temperature of the area and increases the level of humidity. A large quantity of trees are

also planted in Sri Suria itself, improving the air quality and provides shade.

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! There's a primary school located around the corner so the only times where traffic

would get a little congested would be around 7 in the morning, noon time and 6 in the

evening. Other then that, the amount of greenery actually boost up the thermal comfort

level of the site.

5.1.2. Micro-climate Site Context

! The house is located at about a good five meters away from the side neighbour house.

It gives a wider space in between houses, thus giving a better air ventilation quality.

Natural ventilation is the process of supplying and removing air through an outdoor space

without using mechanical system. Wind flows easily in to the house giving it a cooling

effect and lessen the stuffiness in the house as the house also has a high amount of

relatively large windows and sliding doors.

! The direct neighbor on the side of the room has an amount of big trees. It has a

relatively large foliage at about two and a half meters each. And the land behind the house

is a dedicated land of garden which is also filled with nourished trees. Both sides of these

trees gives shade directly to the selected room. The air quality is, too, naturally improved.

Heat is also absorbed as plants carry out the photosynthesis system.

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! In the garden of the house, it has two water features. One is located very close to the

selected analysis room and another is a water fountain in front of the house. There is also

a four meters long swimming pool at the neighbor's house. With this much or water

features around, the humidity level is naturally higher and it helps to decrease the

temperature of the surroundings. Water promotes cooling through evaporation as well as

absorbing heat from surrounding materials. Flowing water promotes air movement which

can cool a space down. Water also has a psychological cooling effect, making a space

seem cooler even if there is no measurable temperature change.

! The garden of the house is mostly covered with grass. It does not have much of

cemented or tiled floor. Grass has the ability to absorb heat into the ground, whereas hard

cemented or tiled floor would reflect the heat up towards the building making it hotter.

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! The overhang of the roof outside the selected room is a meter wide. It gives a partial

shade to the space inside the room. It changes with the time of the day according to how

the sun path moves. It aids a lot in giving shade as it limits the amount of sunlight piercing

through the windows.

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5.2. Solar Radiation

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! The room is facing the south-east direction; therefore it would normally be subject to

morning sun rays. However it is blocked by the neighborʼs tall trees which tower over the

chosen rooms windows. This would prevent the room from heating up in the morning, but

not after the sun is in the noon position.

! Solar radiation would then heat up the house and the area around the chosen room

which would contribute to its increase in temperature during the afternoon, till the sun sets.

! The house has an overhung roof over the window of the chosen house so it does

help shade the area during sunny times. Horizontal sun shading is appropriate in this

application because the area only receives sunlight post-noon when the sun is above the

house so a vertical sun shade would be a waste.

! The house has low-E glass that would reduce solar radiation into the rooms greatly.

Itsʼ room uses clay tiles as well that reflect light and heat effectively. This all contributes to

the reduction of solar radiation.

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5.3. Air Movement and Velocities

5.3.1. Wind

Wind is the product of pressure gradients established between high and low

pressure systems.

! Wind direction, speed and frequency will influence the building design including

bracing requirements, roof and wall cladding selection, weather-tightness detailing,

building entry locations, window size and placement and provision of shelter for outdoor

spaces.

Designing for wind

! Generally, designing for wind will require providing shelter but in hot or humid

climates, the building design may deliberately incorporate features or shapes to provide

cooling breezes for a passive cooling effect. In remote locations, wind speed and

frequency may also be a factor in selecting wind as a power generation source.

! Assessment of wind effects in the design process includes the speed (average and

peak) and direction of wind, and how it affects the site at different times of year.

! The prevailing wind direction must be considered in relation to the design of a

building, in particular, for locations of doors and opening windows, and provision of shelter

for outdoor areas. Other aspects of wind to consider include:

- the direction of the strongest wind

- the direction of the coldest wind

- humid/dry winds

- wind that comes off the sea (salt spray issues)

- the wind direction that brings most of the rain.

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Wind regions and zones

Table 5.3.1

This table provides steps to determine wind zone. From Table 5.3.1, determination of the

wind zone for a particular site requires the following steps:

- Determine the wind region.

- Determine whether in a lee zone.

- Determine ground roughness.

- Determine site exposure.

- Determine topographic class.

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Wind movement on site

Table 5.3.2 Wind rose Diagram

The above wind rose is a graphic tool used by meteorologists to give a succinct view of

how wind speed and direction are typically distributed on site

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! Obstruction of wind by buildings and trees will create a region of highly turbulent

flow. There are some trees behind the selected building, and at the same time there are

some buildings around which are the same height as the selected building. Wind speed is

reduced by the obstacle (trees).

The above diagram illustrates how wind travels around the building during daytime and

night time.

! During daytime, sun heats up the land, causing low pressure at the surface.

However, the interior of building is at a lower temperature compared to the exposed land,

where thereʼs high pressure in the building. Air always travels from a higher pressure

region to a lower pressure region. Ventilation of air occurs from the interior of building to

outside. Wind travels from the lowest temperature trees area (lowest temperature/highest

pressure), to the interior of building (low temperature/high pressure) and at the end to the

warmest empty spaces in front of the building (highest temperature/lowest pressure).

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! During night time, the ratio of difference of temperature and pressure between the

interior of building, trees area and empty spaces in front of building is not large enough to

cause a strong air movement due to the difference of pressure. However, wind travels in

all direction and it travels into the building through openings around the building.

5.3.2. Ventilation

The importance of natural ventilation

1. Human Performance in a Hot Environment

In hot stuffy conditions work has little appeal. People gets tired and they lose

concentration. Human relations suffer and performance drops unavoidability. Research

confirms that uncomfortably high or low temperatures, lack of fresh air movement and high

humidity leads to more accidents.

The actual number of vents required and the air supply necessary makes allowance for

flow resistance based on their exhaust and inlet coefficients. The positioning of the vents

is also critical in order to exhaust the smoke without mixing and cooling them.

2. Natural Ventilation

Natural ventilation is ventilation systems which make use of the existing thermodynamic

forces within a building to draw in fresh air and discharge waste air without the assistance

of machinery or powered components. When the air in a building is heated by solar effect,

product, plant and machinery or other means, it expands, which causes the density to

decrease. This results in a reduction in the mass of a given volume. Should this air then be

exposed to and in contact with

surrounding air that is cooler and heavier, the warmer air will be induced to rise. The rate

at which this air rises depends firstly on the temperature difference between the rising

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column of warmer air and the surrounding cooler air. The greater the temperature

differential, the faster the warm air rises.

3. Stack Height

The rate at which warm air rises also depends on the height through which the

temperature differential is sustained. Because the early theory of ventilation design was

related to chimney stack design this factor is called “stack height” and is defined as being

the vertical distance between the source of cooler air and the upper exit point. Applying

this to a building, the stack height is measured from the fresh air inlet to the throat of the

ventilator. Providing that a temperature differential is maintained through a reasonable

stack height, a natural ventilation system can be invoked by making a hole in the wall of a

building, say a door through which cool air may enter, and a hole in the roof through which

exhaust air may escape. Such natural ventilation systems have been used effectively for

centuries.

4. The EffectS of Wind

Even at low velocity, wind can devastate a ventilation scheme if the shape and position of

the ventilation outlets are not properly designed. Perhaps the most common

misconception is the view that slope mounted ventilators which have openings that

are“offered” to the flow of wind, are reliable. Jack roofs and other exhaust outlet designs

that “catch” wind are equally unreliable. In addition to exhausting warm air, ventilators must

also be designed to preclude the entry of rain and overcome the ill effects of wind. Both

these factors impose influences on the design configuration that, to a greater or lesser

extent, act to the detriment of exhaust performance.

5. Backdrafting

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Backdrafting is the term to describe wind blowing back through an exhaust outlet. The

effect is almost always responsible for inefficient ventilator performance, negative

airflow, or airflow reversal. In addition to reversing the airflow, backdraughting often

reverses the internal drainage geometry of the ventilator, which in turn results in serious

leakage.

Air movement in the building

! During daytime, hot air travels around the building. To achieve optimum thermal

comfort level, fenestrations like windows are mostly closed to avoid the flowing in of hot air

into the house. Curtains are closed as well to prevent sunlight shines into the house

directly. This is to minimize the heat gain.

! During night time, fenestrations like windows are mostly opened to allow heat

gained during daytime to diffuse out of the building (maximize the heat lose). Cold air at

night travels into the building and it forces the hot air out of the building.

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Openings as a factor affecting the ventilation:

The selected building has a distance of 5 meters away from the neighboring houses. Air

can flow into any of the openings of building. Therefore, air is ventilated well in all

directions. Hot air is being brought out through the openings.

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The height of windows from ground level in our case study is around 900mm. Opening at

the level of occupants allows comfort ventilation.

Stack Ventilation

! Stack ventilation occurs in this building to achieve higher quality of thermal comfort.

Stack ventilation is where air is driven through the building by vertical pressure differences

developed by thermal buoyancy. The warm air inside the building is less dense than cooler

air outside, and thus will try to escape from openings high up in the building envelope;

cooler denser air will enter openings lower down. The process will continue if the air

entering the building is continuously heated, typically by casual or solar gains.

! Stack ventilation is one of the two natural ventilation mechanisms, the other being

wind-induced. Since the same openings may contribute to both stack and wind pressure

induced flows, they must not be considered in isolation.

! The effectiveness of the stack effect, i.e. the volume of air that it drives, is

dependent upon the height of the stack, the difference between the average temperature

of the stack and the outside, and the effective area of the openings.

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5.4. Materials

5.4.1. Low-E Glass

! Low-e Glass is a spectrally selective glass option; it reduces long (ultraviolet) and

short wave (infrared) radiation. At the same time allowing visible light to be transmitted

through the glass, an invisible coating is present which dramatically reduces heat transfer

and reflects interior heat back into the space.

! Heat always flows towards cold. Therefore, window glass without a low-e coating

will absorb the cold from your home and radiate it onto the hotter outside surface, where it

heats up the house. Low-e glass that was used in the chosen room has a special coating

which is a poor radiator of heat and does not allow heat to be transferred into the room.

Instead, the low-e coating actually reflects the heat back outside.

! The chosen room faces the east therefore it receives a lot of sunlight in the morning

where the Low E-glass is most useful. The room was able to contain its heat in the

morning and the user did not feel the need to turn on the Air-Conditioner.

5.4.2. Roof Tiles

! Clay tiles are a natural thermal mass insulator, keeping the heat outside. Cooling is

the largest energy consumption in an average house under tropical climate.

Clay tiles have superior solar reflectance and thermal reflectance of up to 86%. Clay tiles

are recognized 'radiators' with their natural ability to limit penetration of radiant heat during

the day, re-emitting heat to the outside at night which enables the house to maintain its

indoor temperature.

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5.4.3. Brick Wall

! Brick buildings, particularly double brick, have excellent thermal mass. Thermal

mass, the ability of a material to retain heat energy when the house is subjected to a

temperature differential, plays a key role in stabilizing temperature changes that the

chosen house area experiences, keeping the internal temperature in the comfort zone

longer and lowers the usage of artificial cooling.

5.4.4. Paint

! White exterior walls absorb less heat than dark walls. And light, bright walls

increase the longevity of siding, particularly on the east, west, and south sides of the

house. The paint color for the chosen room is Light Green therefore if can reflect heat and

makes the room cooler than a darker colored room.

5.4.5. Gypsum Board

! Gypsum board is an excellent fire-resistive building material which makes it an

excellent heat resistant material. The properties of Gypsum board make that has a

combustible core that contains 21% chemically combined. It very effectively retards the

transfer of heat. Gypsum board has an R value of 0.076 Km2/W which measures its

thermal insulation ability. Higher numbers indicate a better insulator.

5.4.6. Aluminum Frame

! Although very strong, light, and almost maintenance free, metal or aluminum

window frames conduct heat very rapidly, which makes metal a very poor insulating

material. Therefore it causes the chosen room to be warmer during the day as heat was

able to penetrate into the room. To reduce heat flow, metal frames should have a thermal

break which is an insulating plastic strip placed between the inside and outside of the

frame and sash. Windows that was not sealed properly can cause heat infiltration inside of

the house. The aluminum frame has an R value of 0.67 h°Fft².

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Conclusion

!

! As a conclusion, we found that the chosen space to be a moderately comfortable

room. Even though it did not comply to the MS1525 Standard for a comfort zone, Itʼs

unique properties enabled it to become a habitable space that could be deemed

comfortable to its users. The temperature average was 31.0 degrees Celsius, which is a

little high but normal for Malaysiaʼs climate. The humidity levels were at a comfortable 68.4

%RH average. This can be attributed to the buildings efficient ventilation. The study gave

us a better understanding of comfort zones and what it means to us. It makes us consider

that finer details in maintaining a comfortable space, which would greatly benefit our future

endeavors.

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Reference

1. Architecture.com (2013). Natural ventilation - stack ventilation. [online] Retrieved from: http://www.architecture.com/SustainabilityHub/Designstrategies/Air/1-2-1-2-Naturalventilation-stackventilation.aspx [Accessed: 15 May 2013].

2. karlbarrett (2012). An Introduction to Microclimate: Considerations In Site Analysis. [online] Retrieved from: http://creativeurbanite.wordpress.com/2011/02/19/back-to-basics-microclimate/ [Accessed: 15 May 2013].

3. Level.org.nz (n.d.). Analysing wind impact on a building site. [online] Retrieved from: http://www.level.org.nz/site-analysis/wind/ [Accessed: 15 May 2013].

4. Timeanddate.com (2013). Kuala Lumpur, Malaysia weather and forecast. [online] Retrieved from: http://www.timeanddate.com/weather/malaysia/kuala-lumpur [Accessed: 15 May 2013].

5. Effect of Building Form on the Thermal Performance of Residential Complexes in the Mediterranean Climate of the Gaza Strip (Huda Muhammed Hussein Abed, 2012) Retrieved at 11.50 pm on May 15th, 2013 from http://library.iugaza.edu.ps/thesis/104557.pdf

6. Improved Pedestrian Thermal Comfort Through Urban Design (Love, J. May 2009)Retrieved at 5.30 am on May 16th, 2013 fromhttp://geoplan.asu.edu/files/planning/JLove_appliedProject2.pdf

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Appendix

Place Date Time Internal Humidity (%RH)

External Humidity (%RH)

Internal Temperature (°C)

External Temperature (°C)

1 4/19/13 23:00:00 71.8 89 30.6 28

2 4/19/13 0:00:00 68.4 94 31.3 27

3 4/20/13 1:00:00 68.4 89 31.1 28

4 4/20/13 2:00:00 68.6 94 30.9 27

5 4/20/13 3:00:00 68.8 89 30.8 27

6 4/20/13 4:00:00 69.2 89 30.6 27

7 4/20/13 5:00:00 69.5 94 30.5 26

8 4/20/13 6:00:00 69.5 94 30.4 26

9 4/20/13 7:00:00 69.8 94 30.3 26

10 4/20/13 8:00:00 70 94 30.2 26

11 4/20/13 9:00:00 71.1 89 30.3 27

12 4/20/13 10:00:00 72.3 89 29.7 27

13 4/20/13 11:00:00 72.4 84 30 29

14 4/20/13 12:00:00 70.9 79 30.4 31

15 4/20/13 13:00:00 69.5 75 30.9 31

16 4/20/13 14:00:00 65.5 71 31.5 32

17 4/20/13 15:00:00 63.8 67 32 33

18 4/20/13 16:00:00 62.8 67 32.4 34

19 4/20/13 17:00:00 63.5 63 32.6 35

20 4/20/13 18:00:00 64.8 67 32.5 33

21 4/20/13 19:00:00 65.2 75 32.4 31

22 4/20/13 20:00:00 65.4 79 32.2 30

23 4/20/13 21:00:00 65.8 79 32 30

24 4/20/13 22:00:00 66.2 89 31.9 29

25 4/20/13 23:00:00 66.6 84 31.7 29

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26 4/20/13 0:00:00 67.4 84 31.5 29

27 4/21/13 1:00:00 66.7 89 31.7 28

28 4/21/13 2:00:00 66.7 89 31.5 28

29 4/21/13 3:00:00 67 94 31.3 27

30 4/21/13 4:00:00 67.4 94 31.2 27

31 4/21/13 5:00:00 68 94 31 27

32 4/21/13 6:00:00 68.4 94 30.8 27

33 4/21/13 7:00:00 68.8 94 30.7 27

34 4/21/13 8:00:00 68.8 94 30.7 27

35 4/21/13 9:00:00 68.9 94 30.8 26

36 4/21/13 10:00:00 68.4 84 31 26

37 4/21/13 11:00:00 69.4 71 30.6 28

38 4/21/13 12:00:00 69.1 71 30.8 30

39 4/21/13 13:00:00 68.7 71 31.2 32

40 4/21/13 14:00:00 67.7 71 31.6 33

41 4/21/13 15:00:00 67.1 71 31.9 33

42 4/21/13 16:00:00 67.3 75 31.9 32

43 4/21/13 17:00:00 67.4 75 31.9 31

44 4/21/13 18:00:00 67.4 79 31.8 30

45 4/21/13 19:00:00 67.4 79 31.7 30

46 4/21/13 20:00:00 67.3 94 31.5 27

47 4/21/13 21:00:00 67.5 94 31.3 27

48 4/21/13 22:00:00 67.9 94 31.2 27

49 4/21/13 23:00:00 68.1 89 31 27

50 4/21/13 0:00:00 68.5 94 30.9 27

51 4/22/13 1:00:00 68.7 94 30.7 26

52 4/22/13 2:00:00 69 94 30.5 26

53 4/22/13 3:00:00 69.3 94 30.3 26

54 4/22/13 4:00:00 69.5 94 30.2 26

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55 4/22/13 5:00:00 69.9 94 30 26

56 4/22/13 6:00:00 70.3 94 29.9 26

57 4/22/13 7:00:00 70.6 94 29.7 26

58 4/22/13 8:00:00 71.1 94 29.7 26

59 4/22/13 9:00:00 71.9 94 29.9 28

60 4/22/13 10:00:00 72.3 89 30 30

61 4/22/13 11:00:00 71.3 79 30.3 31

68.377049 31.014754

max 72.4 32.6

min 62.8 29.7

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