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DESIGN GUIDELINES FOR CLIMATE RESPONSIVE URBAN IN-FILL HOMES IN HOT & HUMID CLIMATES Duy (Nguyen Bao) Vo Synthesis 2012 - 2013 M.Sc. in Sustainable Design Carnegie Mellon University Advisors : Vivian Loftness, Azizan Aziz & Erica Cochran Date: 08/06/2013


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Acknowledgement This synthesis has been an extremely rich and valuable experience for me. It would not have been possible without the following people: My family, especially my parents. Words are not enough to describe how unconditional their love for me has been. Without their sacrifices and constant emotional support, I would not have been able to be here, opening my eyes to see the world full of excitement and rich of knowledge. Professor Vivian Loftness, professor Erica Cochran & professor Azizan Aziz. I would like to express my sincere gratitude for their constant guidance & support on this exciting yet tumultuous learning journey of mine. I would like to thank Dr. Anh-Tuan Nguyen of UniversitÊ de Liège for generously sharing his phD dissertation and the weather files of Ha Noi, Da Nang and Ho Chi Minh City. My climate assessment would not have been successful without his aid. My special thanks to a very special group of colleagues that I have been blessed to have the opportunity to study with: Xiaopeng Ma, Ashwini Arun, Haoyu Feng, Zhengzhao Pei, Annie Rantilla, Vaama Joshi, Pushkala, and Reiko Pahl. I would like to thank the following group of professors and experts for generously offering me their opinions , advices and support: professor Nina Baird (CMU), professor Steve Lee (CMU), professor Alison Kwok (University of Oregon), Ms. Melissa Merryweather (Director of Green Consult Asia) and Patrick Bivona Finally I would like to thank Thao Bui for being my biggest inspiration. Without you and your support, I would have never thought of pursuing such a challenging yet enriching topic such as this one.

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Table of Content I. Abstract II. Methodology III. Expected Outcome IV. Background Research 1. 2. 3. 4. 5. 6. 7.

Vietnam’s Energy Demands Air Conditioning Usage Vietnam’s Climates Overview Ha Noi: Overview Da Nang: Overview Ho Chi Minh City: Overview Vietnamese Tube House

V. Design Guidelines Establishment 1. 2. 3. 4. 5.

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Climate Responsive Design Framework Adaptive Comfort Zone Climate Assessment Climate Responsive Design Strategies Regional Case Studies

VI. Proof of Concept VII. Conclusion VIII. Future Works IX. Bibliography X. Appendices

6 7 8 9 10 11 12 15 16 17 18

20 21 24 26 41 62

124 135 136 137 141


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I. Abstract

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This study aims to combine passive design approach and energy

Vietnamese urban dwellings are said to remain unchanged until the economic reform

conservation into a hybrid set of strategies for designing low energy climate

in 1986, from which point Vietnam has been experiencing an accelerated development

responsive urban in-fill homes in three major Vietnamese cities: Ha Noi, Da Nang

associated with the market-oriented economy. At the rapid rate of urbanization and

and Ho Chi Minh City. The tube house, a narrow, long and multistory residential

modernization, Vietnam witnesses the disappearance of its vernacular urban architecture.

dwelling type, is selected to be the main housing typology for this study as it is

Many traditional tube houses are torn down to make ways for much taller and shorter Neo-

commonly found in many major cities in Vietnam. As the population of many

tube houses. These newly interpreted Tube houses not only have a tube form in plan but

major Vietnamese cities rapidly increase, the magnitude of urban heat island

also a tube form in elevation. Inner yards are often shrunk in size or sometimes completely

effect is heightened. It exerts a significant thermal stress on many Vietnamese

filled up eliminating opportunities for natural ventilation and daylighting. These neo tube

urban dwellers while increasing the energy consumption for cooling, especially in

houses, often occupied by far fewer people than traditionally, are bounded on three sides;

the residential building sector. It is indicated that within the five-year span from

hence the design of the faรงade is consequently emphasized.

2005 to 2010, the energy consumption from the residential building sector

increased by 63.9% (Construction, 2010). This rate is expected to increase

construction projects done in similar climates as those of Vietnam are conducted.They serve

steadily the following years. Additionally, many major cities in Vietnam have

as the basis for the establishment of this illustrated set of design strategies. One potential

been experiencing a rapid rate of urbanization in the past couple of decades as

strategy, selected by the author, is modeled to simulate its overall energy effectiveness. The

rural-to-urban migration increases. This in turn has caused an increase in energy consumption as well as CO2 emission (Satoru Komatsu, 2012). In a research

result of this simulation not only and to reaffirm the validity of the entire solution set but

assessing urban heat island effect in Asian mega cities based on satellite data

comfort, and energy efficiency in tropical climates such as Vietnam. This study stresses the

from 2001 to 2003, Tran, et al. finds that the temperature in Ho Chi Minh city, during the dry season, is 5oC and 2oC different from the surrounding rural

importance of integrating design concepts with climate analysis early in the design process.

areas during daytime and at night respectively (Tran Hung, 2006).

Vietnam that can also be applicable to other similar urban settings.

As part of the study, a series of literature reviews on both previous research and

also indicate the applicability and the effectiveness of certain strategies in achieving thermal

The outcome of this study is an illustrated guideline of high-density residential buildings for


II. Methodology

The methodology of this study includes three sections: Background

These graphical climate assessment tools are as follow:

Research, Design Guidelines Establishment and Proof of Concept

• 2-hour Conditioning Square

Background Research

• Sun Path Diagram

• Wind Rose

This section attempts to provide the context from which the topic of the

• Pyschrometric Chart

study was derived from by first presenting the data found on Vietnam’s annual

This section also identifies the climatic assets and liabilities for each of the three

energy consumption as well as the rapid adoption of air conditioining within the

cities based on the climate assessment. Applicable design recommendations and strategies

country’s urban area. The section then identifies the sub climate zones in Ha

are pinpointed and catalogged according to the assets, liabilities and literature reviews

Noi, Da Nang and Ho Chi Minh City categorized by the Koppen World Map.

on scholarly research and built projects. A series of illustrative diagrams are also included

It also highlights key climatic attributes while providing historical context of

to help communicate the strategies to the potential audience. Lastly, this section displays

these three cities. Additionally, literature reviews on the history and evolution of

twelve case studies of built urban in-fill homes found both inside and outside Vietnam. The

Vietnamese tube houses are gathered here in this section.

strategies used in each of these precedents are identified and related back to the design

Design Guidelines Establishment

guidelines established from this study.

This section provides details into the development process of the design

Proof of Concept

guidelines. It includes a series of literature reviews on both the climate responsive

design framework as well as the most appropriate adaptive comfort range for

the outcome of this study. It highlights the typological parameters for the proof-of-concept

the study. The section also breaks down the climate analysis of the three cities

modern in-fill tube house. Graphical elements such as floor plans, sections and diagrams

using a combination of tools including Autodesk Ecotect Weather Tool, Climate

are displayed to show the design. Lastly, a simulation on the effectiveness and applicability

Consultant, and other graphical climate assessment tools.

of a selected strategy is documented from start to finish.

This section attempts to reaffirm the validity of the design guidelines established as

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III. Expected Outcome

Through the exploration process from this study, the following have been

achieved: 1. Understanding the nuances of doing energy efficient and thermally comfortable home in tropical climates, especially in the three major Vietnamese cities: Ha Noi, Da Nang and Ho Chi Minh City. 2. Understanding the role that prioritization of climatic elements plays in the design process. 3. Understanding the nuances of designing a modern in-fill tube house in a dense urban setting 4. Compilation of design strategies for an energy efficient home in tropical climates of Vietnam 5. Assessment the applicability of these above strategies to different parts of the world that share similar climatic conditions as Vietnam

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IV. BACKGROUND RESEARCH

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1. Vietnam’s Energy Demands As fossil fuel depletion and global warming become more increasingly and inherently problematic, many developing countries including Vietnam struggle to sustain their economic growth while actively reducing their energy consumption. It is indicated that in 2010, the building sector in Vietnam was accounted for between 20% and 24% of the total national energy consumption and this portion is expected to rise significantly (Construction, 2010). Many major cities in Vietnam have been experiencing rapid rate of urbanization in the past couple of decades

(BKWH) 120

101

100

89.94

80 60 47.78

40 22.90

20 0

as rural-to-urban migration increases.This in turn has caused an increase in energy consumption as well as CO2 emission (Satoru Komatsu, 2012). Additionally, urban

ELECTRICITY CONSUMPTION IN VIETNAM FROM 1970-2011

1.79

1.89

Figure 1. Electricity consumption in Vietnam from 1970-2011(Google Public Data Explorer, 2011)

ELECTRICITY CONSUMPTION IN VIETNAM FROM 2005-2010

districts. In a research assessing urban heat island effect in Asian mega cities

(BKWh)

Other

100

island effect and population size, predicting that the aforementioned temperature differences will increase as the densification rate of cities increases. Consequently, this increases the demand for cooling while exerting a significant thermal stress

Residential

78.92

80 62.19 60

2010 consumption 3.33 BKWh

89.94

surrounding rural areas during daytime and at night respectively (Tran Hung, 2006).They also identified a strong correlation between the severity of urban heat

11.46

1970 1975 1980 1985 1990 1995 2000 2005 2010 2011 YEAR

heat island effect has become clearly noticeable in the densely built inner city based on satellite data from 2001 to 2003,Tran, et al. found that the temperature in Ho Chi Minh city, during the dry season, is 5oC and 2oC different from the

4.14

2.93

6.47

47.78

2010 consumption 34.36 BKWh

69.21

Commercial 2010 consumption 4.0 BKWh

54.59

Industrial

2010 consumption 47.22 BKWh

40

Agricultural 2010 consumption 1.0 BKWh

on the local population, especially the elderly and the youth(Waibel R. E., 2009)

20

Total Electricity Consumption (BKWh)

0 2005

10

2006

2007

2008

2009

2010

YEAR

Figure 2. Electricity usage in Vietnam by sector from 2005-2010 (Vietnam Electricity)


2. Air Conditioning Usage

Traditionally, low-energy low-cost cooling strategies were widely

used to fare with the year round heat in vernacular Vietnamese architecture. However, as Vietnam rapidly develops, especially after the economic reform taken place in 1986, its increasingly affluent population has been widely adopting air-conditioning as an alternative means to achieving their desired thermal comfort. A market research in Vietnam by Econoler reported a 30% increase in sales of AC units between 2006 and 2008 for both residential and commercial sectors (Econoler, 2009). Additionally, in a 2009 survey of 414 households in Ho Chi

AC

Minh City, 57% of respondents used AC as a mean to reach thermal comfort. (Waibel M. , 2009) 68% of tube houses were equipped with AC units, while 15% of these had AC constantly operated in all major rooms (Waibel M. , 2009). Only 33% of the tube houses used only

AC

natural ventilation while other 49% used a mix natural ventilation and AC mode (Waibel M. , 2009). Furthermore, the study by Waibel also indicated that the rising middle class of Vietnam would become more accustomed to, and prefers mechanical cooling to natural ventilation in achieving thermal comfort. Having recognized those challenges and changes, reducing energy use, especially the energy consumed by building occupants, is an important priority for Vietnam, as the country constantly faces the energy crisis. Research to reduce energy

Legends AIR CONDITIONER Natural ventilation Figure 3. Findings from the AC usage survey conducted by Dr. Michael Waibel

consumption in buildings while maintaining optimal thermal comfort is essential.

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3. Vietnam Climate Overview a. Tropical Climates Tropical climates, or tropical moist climates, extend northward and southward from the

• Tropical Wet (Af) - This minor climate is characterized by its high annual precipitation (at

equator to 15-25 degrees of latitude(Köppen, 1940) In these climates, all months have average

least 60 mm or 2.4 inches) This climate is dominated by the Doldrums Low Pressure System

temperatures above 18 degree Celsius or 65 degree Fahrenheit. The annual rainfall is constantly

annually, thus not having natural seasons.

greater than 1500 mm or 60 inches. There are 3 minor climates classified under tropical moist

Examples:

climates based on their seasonal distribution of rainfall

o Belem, Brazil o Kuala Lumpur, Malaysia o Singapore City, Singapore • Tropical Monsoon (Am) – This minor climate is resulted from change in seasonal direction of the monsoon winds. Its driest month has significant low rainfall, which is less than 60 mm or 2.4 inches (Köppen, 1940). Examples: oMumbai, India oChittagong, Bangladesh

Central & Southern REGION OF VIETNAM

oYangon, Burma • Tropical Wet and Dry (Aw) - This minor climate is characterized by its pronounced dry season, in which the driest month has the precipitation less than 60 mm or 2.4 inches (Köppen, 1940)

TROPICAL RAINFOREST CLIMATE (AF) TROPICAL monsoon CLIMATE (Am) TROPICAL wet & dry CLIMATE (Aw)

Examples: Source: koppen tropical climates map retrieved via http://en.wikipedia.org/wiki

Figure 4. Tropical Climates World Map

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TROPICAL CLIMATES WORLD MAP

o

Chennai, India

o

Lagos, Nigeria

o

Bangkok, Thailand


3. Vietnam Climate Overview b. Humid Subtropical Climates Humid subtropical climates are characterized by warm summers and warm to cool winters. There

• Humid subtropical with no distinguished dry season (CFA) – This minor climate is characterized with average temperature of the warmest month to be over 22oC/72oF.The average temperature

may be either even distribution of the annual precipitation throughout the year or a noticeably dry

of the coldest month is typically under 18oC/64.4oF and above -3oC/26.6oF. This climate has

season.

even distribution of precipitation throughout the year (Troy Kimmel, 2006)

These climates are categorized under Mild temperate/ mesothermal climates group (C).

Examples: o Shanghai, China o Taipei, Taiwan o Austin, Texas, USA o Tampa, Florida, USA • Humid subtropical with dry winter (CWA) - This minor climate is characterized with average temperature of the warmest month to be approximately 22oC/72oF.The average temperature of the coldest month is typically under 18oC/64.4oF and above -3oC/26.6oF. This climate has

NORTHERN REGION OF VIETNAM

a distinctly dry winter, when the precipitation is 10 times less than the wettest summer month (Troy Kimmel, 2006) Examples:

HUMID SUBTROPICAL WITH NO DISTINGUISHED DRY SEASON(CfA) HUMID SUBTROPICAL WITH DRY WINTER (CWA)

Source: koppen subtropical climates map retrieved via http://en.wikipedia.org/wiki

Figure 5. Humid Subtropical Climates World Map

HUMID SUBTROPICAL CLIMATES WORLD MAP

o Delhi, India o Salta, Argentina o Hong Kong, China o Guadalajara, Jalisco, Mexico

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3. Vietnam Climate Overview c. Climates of Vietnam

North East

Because of many topographic differences, the climate of Vietnam tends to vary significantly from place to place within the country.

NORTHWEST

There are 3 apparent minor climates in Vietnam: humid subtropical

RED RIVER DELTA North central coast

climate (Cwa), tropical monsoon climate (Am) and tropical wet and

Ha Noi (21.2oN : 105.79oE) Humid subtropical (CWA)

dry (Aw)

o Humid Subtropical Climate with dry winter (Cwa) – North

East, Red River Delta, and North West

o Tropical Monsoon Climate (Am) – North Central Coast and

Mekong River Delta

CENTRAL HIGHLANDS

o Tropical Wet and Dry (Aw) – South East, Central Highlands

DA NANG(16.07oN : 108.23oE) Tropical Monsoon (Aw)

SOUTH central coast

Ho Chi Minh city (10.75oN : 106.67oE) Tropical wet & dry (Aw)

and South Central Coast

Annual rainfall is significant in all regions and torrential in

some (1200 to 3000 mm or 47.2 to 118.1 inches) Annual humidity level is approximately 80%. Seasonal division is more pronounced in the Northern region of Vietnam, as compared to the Southern and Central

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SOUTHEAST CLIMATE ZONES OF VIETNAM

REGIONS OF VIETNAM

MEKONG RIVER DELTA Figure 6. Regions of Vietnam

Figure 7. Climates zones in Vietnam


HA NOI

4. Ha Noi: Overview Ha Noi, previously named Thang Long, is the capital of Vietnam. Due to the length of its development in Vietnamese history, it is both political and cultural capital of the country with multitude of historical landmarks, buildings located in

Square milage POPULATION Population DENSITY

various sites throughout the city. The city is located on the bank of the Red River. Ha Noi has a population of 6.23 million people with a total square milage of

Ha Noi is located within the humid subtropical with dry winter climate

Ha Noi

4828 people/mile

2

Figure 8. Overview of Ha Noi

CLIMATIC CONDITIONS OF HA NOI, vIET nam

1291, making the city the second densest city out of the 3 cities examined in this study (4828 people/sq. mile)

1291 mile2 6.23 million

(%) 100

(째F) 100

classified the Koppen Climate Classification system, with an average humidity of 78.8%. Unlike the other 2 cities, Ha Noi does have four seasons. Summers

90

80

(occurring from May to September) are typically hot and humid with average rainfall of approximately 1680 mm or 66.1 inches, while winters (occurring from November to March) are relatively dry and colder in comparison to the national standard. Spring (April) usually comes with light rain while Autumn (October) is desirable temperature-wise.

80 60 70 40

60

20

50

0

40

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Average Temperature (째F)

Average Low Temperature (째F)

Average High Temperature (째F)

% Humidity

Figure 9. Annual emperature conditions & humidity levels in Ha Noi

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DA NANG

5. Da Nang: Overview Da Nang, along with Ho Chi Minh city and Hai Phong, is not only an important port city but also a transportation hub of Vietnam. It was previously part of Quang Nam province, however in 1997, it was separated to be its own municipality. Da Nang has a population of 0.95 million people with a total square

Square milage POPULATION Population DENSITY

milage of 484.76, making the city the least dense city out of the 3 cities examined

Figure 10. Overview of Da Nang

in this study (1963 people/sq. mile) Da Nang is located within the tropical monsoon climate (Aw) classified by the Koppen Climate Classification system, with an average humidity of

484.76 mile2 0.95 million 1963 people/mile2

CLIMATIC CONDITIONS OF dA nang, vIET nam

(%)

DA NANG CITY

100

(°F) 100

75%(WeatherBase: Historical Weather, 2012). The year is divided into 2 seasons: rainy season (occurring from September to March with average rainfall of approximately 2044 mm or 80 in.) and “dry” season (occurring from April to August with the highest temperature reaching 41oC or 107oF)

90

80

80 60 70 40

60

20

50

0

40

Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Average Temperature (°F)

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Average Low Temperature (°F)

Average High Temperature (°F)

% Humidity

Figure 11. Annual temperature conditions & humidity levels in Da Nang


Ho Chi Minh city

6. Ho Chi Minh City: Overview Ho Chi Minh city, or formerly Saigon, was the capital of the republic of Southern Vietnam. After the “Fall of Saigon” in 1975, the city was then merged with the surrounding province of Gia Dinh and later renamed after the late Ho

Square milage POPULATION Population DENSITY

Chi Minh. The name Saigon, however, is still commonly used amongst many local Vietnamese who reside within the city. Ho Chi Minh city has a population of

Ho Chi Minh city is located within the tropical dry and wet climate (Aw)

9579 people/mile2

Ho chi minh city

Figure 12. Overview of Ho Chi Minh City

7.75 million people with a total square milage of 809, making the city one of the world’s densest cities (9579 people/sq. mile)

809 mile2 7.75 million

CLIMATIC CONDITIONS OF HO CHI minh city, vIET nam

(%) 100

(°F) 100

classified the Koppen Climate Classification system, with an average humidity of 80%(WeatherBase: Historical Weather, 2012). The year is divided into 2

90

80

seasons: rainy season (occurring from May to November with average rainfall of approximately 1800 mm or 71 in.) and dry season (occurring from December to April, with the highest temperature reaching 39oC or 102oF

80 60 70 40

60

20 0

50 Jan Feb Mar Apr May June July Aug Sep Oct Nov Dec Average Temperature (°F)

Average Low Temperature (°F)

Average High Temperature (°F)

40

% Humidity

Figure 13. Annual temperatures & humidity levels in Ho Chi Minh City

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7. Vietnamese Tube House

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a. Traditional Tube House

Vietnamese Tube House dates its conception back to the Le Dynasty (15th- 18th century) in

voids and masses in order to ensure good natural ventilation, and lighting. Traditional Tube

Ha Noi old quarter, as a result of a feudal tax law established in 15th century. It is indicated that as

house basic structure consists of similar (or even identical) modules made of static wooden

settlement in Ha Noi old quarter was gradually populated by rural migrants, a feudal government

structure, which can be easily and massively replicated. As a house gets more populated with

act had been enforced to tax shops by their front widths (To, 2008) As a result, the front parts were

additional occupants, it gets expanded inward through either partial development of courtyards

divided smaller, approximately 2.5-3 meter or 8-10 feet. As vacant land got filed up, the houses

or addition of new masses. Furthermore, traditional tube houses, with their 2-story facades, not

consequently were expanded inwards making them longer and shaped up to the tube form with

only allow for perfect audio-visual communication between the residents and people from the

a total length up to 50-100 meters or 164-328 feet.

street but also create an engaging human-scale street front (To, 2008)

Figure 14. A traditional tube house found in Da Nang

The architectural concept of Vietnamese Tube House is simple yet allowing for great eco-

sufficient spatial composition. Most traditional tube houses are made of a series of alternating

Figure 15. Illustrative diagram of traditional tube houses


b. Neo Tube House

Vietnamese urban dwellings remained unchanged until the economic reform in 1986, from

which point Vietnam has been experiencing an accelerated development associated with the market-oriented economy. At the rapid rate of urbanization and modernization, Vietnam witnessed the disappearance of its vernacular urban architecture. Many traditional tube houses were torn down to make ways for much taller and shorter Neo-tube houses. These newly interpreted Tube houses not only have a tube form in plan but also a tube form in elevation. Inner yards are often shrunk in size or sometimes completely filled up eliminating opportunities for natural ventilation and day lighting..

These neo tube houses are bounded on three sides; hence the design of the faรงade is

consequently emphasized with deliberate use of bright colors, modernist compositions as well as colonial architectural details. Since the dwelling size is currently used to express wealth rather than being derived from necessity, far fewer people live in these taller neo tube houses (Groves, 2006). In addition, it is a common practice in modern Vietnam to have both commercial and residential spaces present in the home. This then propagates the upward building practice of many homeowners, who want to maximize the commercial benefits of their homes.

A typical Neo Tube House is comprised of reinforced concrete structure with brick and

plastered walls. Due to the simplicity of the overall structure as well as the inexpensive nature of local labor and materials, these tube houses are rarely retrofitted. In the case of ownership churn, they are completely demolished to make ways for new construction. 89% of the tube houses

Figure 17. Illustrative diagram of Neo tube houses

surveyed in a study conducted by Dr. Waibel in 2009 were built within 14 years of the date of the study (Bivona, 2012) (Waibel M. , 2009).

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V. DESIGN GUIDELINES ESTABLISHMENT

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1. Climate Responsive Design Framework “Climate is clearly one of the prime factors in culture, and therefore built form. It is the mainspring

Given the climatic conditions, energy consumption projection and current urban housing

for all the sensual qualities that add up to a vital tropical architecture” – Tan Hock Beng

typology of Vietnam, this study aims to craft a design approach in which these parameters are addressed. The question raised is how should this best be carried out. The argued approach here is to establish a design process where a series of decisions are made to further emphasize the relationship of 3 following elements: people, climate and energy. This is achieved through the use

People

of site, building form and fabric, plant and equipment and social notion of comfort. Over the past few decades, various design approaches, as subsets of the environmental design framework, have been established in order to address said relationship, yet none of them has proactively

CLIMATE

ENERGY

addressed all three aforementioned elements. The proposed set of design strategies for this study will attempt to equally take into account people, climate and energy.

FRAMEWORK OF DESIGN

In order to help establish the framework upon which this study would be based, I looked

to bioclimatic design as well as PassivHaus standard for precedents. While bioclimatic design is deeply rooted in the relationship between human comfort and climatic conditions, PassivHaus

BUILDING FABRIC

SITE

focuses heavily on energy conservation. Though fundamentally different, once strategically

EQUIPMENT

COMFORT

combined, they possess the potentials to effectively address the elements of people, climate and energy. The study aims to carefully assess the effectiveness and transferability of each individual strategy of the two approaches in dense tropical urban setting of Vietnam, and eventually provide a recommended set of strategies.

ACTIVE

PASSIVE

HYBRID

In his book “Climate Responsive Design”, Richard Hyde stated that the “ordering of

climate design strategies suggests that some have a greater impact on climate response than others and this has a bearing on the focus of the design decision-making process” (Hyde, 2000).

Figure 18. Framework of ecological design In the wake of energy crisis and global warming, it is essential to stress the importance of built form relating to “the climate of a place to produce passive low-energy buildings” (Yeang, 2005)

This implies a level of hierarchy in decision-making. However, this hierarchy is not rigid across climates and models, but rather is derived from the context of the design, occupants’ needs and the building site itself. Hyde highlighted the following three sets of factors, as they are related to the filtering mechanism of a building that acts as a climate filter (Hyde, 2000):

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1. Climate Responsive Design Framework •

Microclimate, macroclimate and topography

Building form and fabric

(Olgyay, 1992; Yasmin Bhattacharya, 2009). His method was based on a “bioclimatic” chart

Plant and equipment

that aimed to show human comfort zone in relation to the dry bulb temperature (y-axis) and

However, this study proposes the inclusion of the social notion of comfort as an additional factor

relative humidity (x-axis)(Liu Yang, 2005). He also considered the effects of mean radiant, wind

to the previous three. The idea behind this consideration is stemmed from an article called

speed and solar radiation. Later in 1976, Baruch Givoni developed building climatic charts

“Social Loading and Sustainable Consumption” by Loren Lutzenheiser and Harold Wilhite. The

based on typical psychrometric charts (Givoni, 1976)

authors highlighted the link between changes in the notion of comfort in a typical Japanese

household and certain social changes such as clothing norms and “modern” family view. They

architecture worldwide, many of which greatly reflect their environmental, cultural and historical

speculated that status indicators “vary both across and within each society, however, and the

context in which they exist (Manoj Kumar Singh, 2009). However, vernacular architecture may

nature of those indicators influence social load. A common thread across industrial societies is

not be an appropriate solution for modern architecture today due to our current social and

that the consumption of things confers status, thus increasing load, but this is done in different

physical context. Additionally, our proliferated technical capability will also have prevented us

ways in different countries” (Wilhite, 1999). This is certainly true in the case of a developing

from reverting back to the old-fashioned built forms(Manoj Kumar Singh, 2009). Vernacular

country such as Vietnam. As the middle class grows bigger and becomes more affluent, they

architecture, instead, should serve as a great precedent to modern sustainable architecture

are more likely to remove what is considered “vernacular” or “traditional” in their lifestyle and

since it not only addresses energy-related issues, but also reflects greatly the cultural setup,

households in order to become “modernized”. As a result, passive conditioning strategies lose

socio-economic status as well as the environmental context in which it exists.

their place to mechanical conditioning systems, which means the notion of comfort is changed.

The four set factors identified above, similarly to what had been suggested by Michael Hyde in

manifested in the works of vernacular architecture in hot and humid climates. These precedent

his “Climate Responsive Design” book, are used to formulate 3 building models: passive, active

studies, along with those of contemporary period, will enable me to assess the effectiveness of

and hybrid.

certain strategies, as well as to gain some important insights into the necessary design process

a. Passive Model - Bioclimatic Design

for doing an energy efficient and thermally comfortable home in hot and humid climates.

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Victor Olgyay first proposed the systematic approach of bioclimatic design in the 1950s

This model is achieved through the combined use of site (microclimate, macroclimate, and

Bioclimatic design concepts are linked to numerous different types of vernacular

In the case of this particular study, I will be revisiting bioclimatic design strategies that were

b. Active Model - PassivHaus Standard

topography) design considerations, built form and fabric, and lastly adaptive notion of comfort.

This model is achieved through the combined use of plant and equipment considerations,

Bioclimatic design approach is a great example of the passive model

man-made energy and universal notion of comfort.


Darmstadt house and the GroB-Umstadt house into the PassivHaus standard in 1995. This

c. Hybrid Model

standard was conceived to establish specific energy and quality requirements for new homes in

This model is the overlapped of the two models above

Wolfgang Feist codified passive design strategies used in the construction of both the

cold central Europe. The Passive-On project sought to adapt the PassivHaus standard, originally developed in Germany, to the climates of France, UK, Italy, Spain and Portugal (eERG, 2011).

Model(s)

Although the Passive-On guidelines do address the design of energy efficient home for climates

Notion of Comfort

PHIUS has been working on a home in Lafayette, Louisiana based on Passive House

Adaptive Comfort

Active Model

Universal Comfort

•This model guarantees a constant level of global thermal comfort

Adaptive Comfort

•This system uses plant and equipment to maintain desirable thermal comfort at low energy intake level. •This model uses microclimate • Due to diurnal & seasonal and building fabric to provide changes, it is difficult to manage passive means to reduce the effectiveness of this model. energy. •This model is ideal since it addresses both energy and thermal comfort well.

conditions with dry bulb temperatures reaching 100 degree Fahrenheit, the cooling needs are still present. A few new Passive House projects have started experimenting with climates that have much more pronounced cooling demand as well as higher level of humidity (e.g. NAMA simulation software, WUFIª, is capable of taking into account of thermal mass, convection and humidity storage, which are important issues that practitioners have to deal with when designing for tropical climates.

PassivHaus standard, as previously stated, emphasizes the importance of energy

conservation through the deliberate construction of super airtight, super insulated buildings. This particular approach, though highly effective in cold climates, seems like a counter-intuitive option for practitioners in tropical climates where heat and humidity level remain unfavorable year round. In addition, vernacular architecture in these climates has always been embracing the connection between occupants and their surrounding nature through the deliberate use of lightweight structure, highly permeable built forms, and natural conditioning methods. However, due to an increased usage of air conditioning units in residential buildings as well as rapid rate of urbanization, PassivHaus standard becomes relevant.

• Performance of the model is highly variable due to the highly variable climatic conditions. • The success of this model requires careful design, and climate assessment. • High casual gains are often resulted. • The efficiency & local thermal comfort are the biggest challenges to this particular model. • Oversizing of systems & redundancy in system deployment in order to accommodate for peak loads

Passive Model

standard. Even though the climate of Louisiana has high level of humidity and hot summer

housing, Qatar Passive House). Additionally, the newly developed energy performance modeling

Disadvantages

•This is a free running system in which internal temperature follows that of the climate. •Thermal performance of this model will be kept at the external shade temperature

that have hot summer, they are not able to address the possibility of doing such home in hot and humid climates, where cooling demand is high annually.

Advantages

Hybrid Model

Figure 19. Table of advantages & disadvantages for the 3 building models (Hyde, 2000)

23


d. Proposed Solution Set

The set of design solutions proposed by this particular study is of the hybrid model. It will

“modernized” lifestyle. For instance, as a result of the Westernization process in Japan, business

be the overlapped of the passive model (bioclimatic design) and the active model (Passivhaus

suit is currently mandatory in most white-collar work regardless of season or temperature(Wilhite,

standard). Adaptive thermal comfort also will be used as to maximize the effective temperature

1999). As a result, the thermostat has to be lowered in order to keep the employees in a

range, which should ultimately assist with the energy reduction from air conditioning within the

Japanese office building thermally comfortable. Similarly, not so long ago, most Japanese would

home. Due to the climate-driven focus of this study, each of the proposed strategies will be

sleep in what was “living space” during the day. This kind of arrangement was seen to be very

identified according to the following steps:

efficient as it had been in earlier European or American homes. However, “Today, the bedroom

Step 1: Evaluate climate data

has arrived on the scene in Japan and the shared bedroom is on its way to becoming extinct in

Step 2: Identify strategy

other industrial societies, too.” (Wilhite, 1999)

Step 3: Identify specifications of strategy

Step 4: Identify Architectural examples

Westernization process in many developing countries such as Vietnam. Today, social factors

Step 5: Illustrate design strategy

play a significant role in determining what is “comfortable” (Lawrence Agbemabiese, 1996).

However, in the wake of globalization, people of developing countries are quickly removing

themselves from what once was of intrinsic value to their indigenous cultures, and adopting

The notion of comfort, too, has evolved and changed drastically as a result of the

The notion of comfort is no longer a derivative of only physiological attributes but has become

2. Adaptive Comfort Zone a. Social Notions of Comfort

24

It is commonly observed that in developing countries, traditional lifestyles revolve around

influenced by social forces. Many Vietnamese acquire air conditioning as the society is becoming more increasingly affluent. To them, air conditioners are as much a social symbol of wealth and modernity as the number of floors and the modernist western-inspired façade of their tube house. The comfort standard has been universalized to align with the Western lab-derived standard of comfort: 25oC and 50% humidity

b. Selected Adaptive Comfort Zone

the prevailing climatic conditions (Lawrence Agbemabiese, 1996). Based on that observation, it

is safe to assume that there is no such universal standard of human comfort, but rather what is

not as applicable as one might think in the tropics. He conducted an assessment on thermal

perceived as “comfortable” is greatly varied amongst different individuals living in various different climatic contexts. This is mainly due to “human body’s ability to adapt to prolonged exposure to

comfort of 1100 workers in both naturally ventilated and air-conditioned buildings in Thailand. ASHRAE standard defines the comfort zone to be within the range of 23oC to 26oC. Busch

certain environmental conditions” (Lawrence Agbemabiese, 1996). The individual variability of

used “the same criteria for thermal acceptability as in the ASHRAE guidelines” (Lawrence

comfort is closely related to a slew of factors such as ailments, physiological conditions, training,

Agbemabiese, 1996) and identified a much broader temperature range than ASHRAE standard – from 22oC to 30.5oC (Busch, Thesis Dissertation, 1990)

diet, clothing habits, living habits, sex, age, etc.

A study by John Busch in 1990 has indicated that the Western-derived comfort norms are


Busch also found that “workers in naturally ventilated buildings were typically comfortable at temperatures 3oC higher (up to 31oC) than were workers in compressor-cooled buildings (up to 28oC)” (Lawrence Agbemabiese, 1996)(Busch, Thesis Dissertation, 1990). The upper comfort temperature for ASHRAE temperature, which was developed for 40oN latitude, can have additional 1K for every 12o shift in latitude to the South. Since Ho Chi

Minh City, Ha Noi, and Da Nang are located at 10.75oN, 21.04oN and 16.06oN respectively, their according upper comfort temperatures are 28.4oC, 27.58oC and 28oC respectively. These temperatures correspond to the findings in Busch’s study for compressor-cooled buildings.

The findings from Busch’s study have a significant impact in the context of Vietnam,

where the optimized “comfortable” temperature in most buildings has been adjusted to be 25oC. This, coupled with a finding that 1oC decrease in indoor temperature equates to 3-10% saving in energy use from air-conditioning , stresses the relevance of building design since it, if appropriately done, can assist with achieving thermal comfort a relatively low energy intake level. Consequentially, the comfort range from 22oC to 30.5oC identified by Busch is used for the climate assessment of the three cities.

25


3. Climate Assessment a. Overview

As previously mentioned, this study aims to combine energy conservation strategies and

of analyses on dry bulb temperature, humidity level, sky coverage, global horizontal radiation,

passive design approach in order to properly address the relationship of people, climate and

sun path, and prevailing winds are then conducted with the aid of various graphical climate

energy. The framework of this study places a heavy emphasis on climate assessment as it

assessment tools. Lastly, climatic assets and climatic liabilities are identified and prioritized to

informs design solutions that respond accordingly to specific climatic conditions. With that said,

assist with the selecting of applicable design strategies for each of the 3 cities.

the climate assessments of the 3 Vietnamese cities examined in this study are conducted in a

b. Graphical Climate Assessment Tools

similar fashion to that of the regional guidelines for building passive energy conserving homes proposed by the U.S Department of Housing and Urban Development. These guidelines were

conditions for each of the 3 Vietnamese cities: Ha Noi, Da Nang, and Ho Chi Minh City. A series

established based on the idea that, “the basis for effective energy conscious design is responding

i. 2-hour Conditioning Square

to the liabilities and assets in your climate which determine the mechanical system’s loads and

resulting energy use.” (AIA Research Corporation, 1978)

distribution of 2-hourly data on various climatic aspects such as temperature conditions, sky

Climate responsive design strategies reduce reliance on mechanical systems to achieve

coverage, humidity levels and global horizontal radiation. For this study, the conditioning squares

occupant’s thermal comfort as well as the building’s overall energy consumption. In order to

are first generated from weather files of the three cities using Climate Consultant and then

proceed successfully with this approach, practitioners must take into account temperature,

recreated for illustration purposes.

humidity, wind, and sun as they define the climatic environment in which buildings are intended

26

The climate assessment process carried out in this study first identifies the basic climate

A 2-hour conditioning square is a time table that can be used to display the monthly

to operate. Depending on the location, practitioners may employ different strategies to protect

ii. Wind Rose

the building from some of these climatic forces and take advantage of other forces in order to

Wind rose is a graphic tool for visualizing wind patterns for any specific site. It provides “ a very

significantly reduce energy demand for mechanical systems. In other words, regional variations of

succinct but information-laden view of how wind speed and direction are typically distributed

temperature, humidity, wind, and sun dictate whether these forces can be either a liability or an

at a particular directions” (United States Department of Agriculture). A typical wind rose chart

asset to the building’s overall energy consumption. With that said, it is important for practitioners

displays distribution of wind speed, wind direction and relative frequency over a given temporal

to understand the basic climatic condition of a specific location before highlighting the climatic

range. There are a considerable variety of wind roses used in different climate analysis software.

assets and liabilities using the various graphical climate assessment tools such as conditioning

While the graphical elements are often different, the type of information displayed is the same.

square, wind rose, sun path diagram and psychrometric chart.

For this particular study, the wind roses for the 3 Vietnamese cities were generated using Autodesk


Ecotect with the hourly weather data specific to these cities.

A typical wind rose chart generated by Autodesk Ecotect comprises of 16 angular wedges,

iii. Sun Path Diagrams

each making up for “an arc of 22.5o around the entire circle. The overall radius of each wedge

represents the percentage of time that the wind came from that direction during the calculation

between air temperature and humidity while relating human thermal comfort conditions to

period.” (Autodesk, 2012) Each of these 16 wedges displays 8 different colored segments. Each

climate data (Yasmin Bhattacharya, 2009). It can be used to plot the temperature and humidity

of these segments represents “the speed of the wind when it was coming from a particular

data collected for the entire 8760 hours of the year; thus it is an immensely useful tool to

direction.The radius of each colored segment (and therefore its size) shows the relative percentage

illustrate aspects of thermal comfort conditions (Yasmin Bhattacharya, 2009). For this particular

of time that the wind from that direction was within that speed range”(Autodesk, 2012).

study, 3 psychrometric charts were created for Ha Noi, Ho Chi Minh city and Da Nang using 3

iii. Sun Path Diagrams

Psychrometric chart, first developed by Baruch Givoni, graphically presents the relationship

different weather files.The weather file of Ha Noi was collected from the DOE website, whereas the weather files of both Da Nang and Ho Chi Minh City were generated from a software

Sun path chart is a graphic tool specifically used for depicting the path of the sun in terms

called Meteor. In order to accurately present the distribution of daily temperature and humidity

of its elevation, azimuth angles over particular times of the day. It provides helpful summary

conditions that occur over the 12 months of the year for each city, daily weather data for every 2

of solar position that architectural designers can refer to when devising shading requirements

hours were processed and averaged for each month of the year. The data then was color-coded

and strategies for any particular location. In a sun path diagram, “North is defined to have an

by months and plotted onto the psychrometric chart. The resulting chart displays 12 different

azimuth angle of 0o and South has an azimuth angle of 180o.” (Solar Radiation Monitoring

diurnal loops representing the temperature and humidity points that occur every 2 hours during

Laboratory, 2013) Typical sun path chart can be plotted in either Cartesian or polar coordinates.

each month. Please see Appendix A, Appendix B, and Appendix C for more details.

Cartesian sun path chart typically displays “solar elevation on one axis and the azimuth on the other at the right angles to the first axis” (Solar Radiation Monitoring Laboratory, 2013). Polar

c. Side by Side Climate Assessment

coordinates “are based on a circle where the solar elevation is represented by smaller and

In order to understand the subtle climatic differences amongst the 3 cities examined in this

smaller circles as the elevation increases and the azimuth is the angle going around the circle

study, analyses of the following elements are displayed side by side:

from 0° to 360° degrees.” (Solar Radiation Monitoring Laboratory, 2013)

Dry Bulb Temperature

For this particular study, the sun path diagrams for the 3 Vietnamese cities were retrieved

Global Horizontal Radiation

using Ecotect Weather Tool. These charts are of stereographic projection, which means that they

Sky Coverage

were plotted using polar coordinates. The daily temperatures from sunrise to sunset were then

Humidity Levels

manually plotted in these sun path charts in order to provide clues to the shading requirements

Prevailing Winds

for each of the 3 cities.

Sun Path

27


Monthly average dry bulb temperature distribution by time of day in the 3 cities Cooling is a must here since the temperatures are above 27oC.

Sunrise

00:00

00:00

00:0

02:00

02:00

02:00

04:00

04:00

04:00

06:00

Sunset

Cooling demand will be high throughout the year in Ho Chi Minh city since the temperatures are consistently above 21oC

Heating is necessary here since the temperatures are below 21oC

Heating would be beneficial here

Sunrise

06:00

These 2 time periods would require some heating since temperatures are below 21oC.

HA nOI - DRY BULB TEMPERATURE (Oc)

08:00

08:00

10:00

10:00

10:00

12:00

12:00

12:00

14:00

14:00

14:00

16:00

16:00

16:00

18:00

18:00

Sunset

20:00

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Cooling is a must here since the temperatures are above 27oC.

Sunset

20:00

22:00

22:00

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Cooling is a must here since the temperatures are above 27oC.

DA NANG - DRY BULB TEMPERATURE (Oc)

HO CHI MINH CITY - DRY BULB TEMPERATURE (Oc)

27OC - 38OC (37%)

< 0OC (0%)

27OC - 38OC (38%)

< 0OC (0%)

27OC - 38OC (65%)

0OC - 21OC (29%)

> 38OC (0%)

0OC - 21OC (5%)

> 38OC (0%)

0OC - 21OC (0%)

> 38OC (0%)

21OC - 27OC (56%)

18:00

20:00

< 0OC (0%) 21OC - 27OC (32%)

28

06:00

08:00

22:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Sunrise

21OC - 27OC (34%)

24:00


Monthly average dry bulb temperature distribution by time of day in the 3 cities OVERALL OBSERVATION

OVERALL OBSERVATION

OVERALL OBSERVATION

29% of the year, Ha Noi’s temperature conditions fall inside the range of 0oC and 21oC whereas the range of 21oC and 27oC is experienced 32% of the year. Ha Noi’s temperature conditions reach their peak during the months of May, June, July, August, September, and October. From June to August, the temperature remains constantly high during both the day and the night. Based on the dry bulb temperature’s conditioning square, the wintry weather in Ha Noi occurs from December to March whereas the summer weather occurs from May to October. Spring season occurs only in April, while autumn season occurs only in November.

5% of the year, Da Nang’s temperature conditions fall inside the range of 0oC and 21oC whereas the range of 21oC and 27oC is experienced 56% of the year. Da Nang’s temperature conditions reach their peak during the months of March, April, May, June, July, August, September, and October. Throughout the year, the temperatures remain below 27oC before sunrise. Based on the dry bulb temperature’s conditioning square, the wintry weather in Ha Noi occurs from December to February whereas the summer weather occurs from April to October. Spring season occurs only in March, while autumn season occurs only in November.

34% of the year, Ho Chi Minh City’s temperature conditions fall inside the range of 21oC and 27oC whereas the range of 27oC and 38oC is experienced 65% of the year. Throughout the year, the temperatures remain within the range of 21oC and 27oC before sunrise. There is no clear indication of the four typical seasons based on the temperature variance in Ho Chi Minh City. Having recognized the frequency of high temperatures in this city throughout the year, cooling will definitely be necessary to ensure occupant’s thermal comfort.

MONTH-TO-MONTH ANALYSIS

MONTH-TO-MONTH ANALYSIS

MONTH-TO-MONTH ANALYSIS

•January & February: the dry bulb temperatures during the 24-hour period

sunrise and after sunset of these two months remain consistently within the range of OoC and 21oC. .However, it is important to note that March has more hours during the day (9 hours) that fall within the range of 21oC and 27oC as compared to December (4 hours).

As indicated in the conditioning square, March signals the start of the hot season in Da Nang with an increase in dry bulb temperatures during the day. The temperatures during the day continue to rise and remain for more hours during the 24-hour period in May, June. Da Nang’s hottest period reaches the peak in July. After July, the temperatures gradually drop and the nighttime becomes cooler. From November to February, Da Nang experiences a cooler period with some hours within the range of 0oC and 21oC.

Unlike Ha Noi and Da Nang, Ho Chi Minh City does not have four clearly defined seasons due to the lack of variance in dry bulb temperatures during the 12 months of the year. The dry bulb temperatures throughout the year fall within only 2 temperature ranges: 21oC – 27oC and 27oC and 38oC. The dry bulb temperatures during the day remain consistently within the range of 27oC and 38oC, whereas the dry bulb temperatures during the early morning hours remain within the range of 21oC and 27oC.

•November: this month witnesses the drop in dry bulb temperature during the

•March: this month signals the beginning of the hot period in Da Nang, as the

hours of early morning. Overall the dry bulb temperatures remain within the range of 21oC and 27oC.

dry bulb temperatures, especially from 11:00 to 17:00, increase. The early morning and nighttime temperatures still remain within the 21oC - 27oC range.

•April: the dry bulb temperatures during the 24-hour period of this month

•July: the dry bulb temperatures remain within the range of 27oC and 38oC for

remain consistently within the range of 21oC and 27oC.

the most hours (19 hours) during this month. It can be considered the peak of Da Nang’s hottest period.

of these two months remain consistently within the range of 0oC and 21oC.

•December & March: the dry bulb temperatures during the hours prior to

•June, July & August: the dry bulb temperatures during the 24-hour period of these 3 months remain consistently within the range of 27oC and 38oC. Cooling will be necessary to ensure occupant’s thermal comfort.

•November: the dry bulb temperatures remain within the range of 21oC and

•May, September & October: The dry bulb temperatures during the

•December, January & February: the dry bulb temperatures during the

24-hour period of these 3 months fall within both 21oC – 27oC range (during the night) and the 27oC – 38oC range (during the day). May signals the start of summer weather in Ha Noi with an increase in dry bulb temperatures whereas September and October signal the end of summer weather with a decrease in dry bulb temperatures during the day and night.

early morning hours of these 3 months fall within the range of 0oC and 21oC, whereas the the rest of the hours lie within the range of 21oC and 27oC.

•April and May: the dry bulb temperatures remain within the range of 27oC and 38oC for the most hours (20 hours) during these 2 months. The temperatures start rising shortly after sunrise (7:00 am) and remain consistently high until 3:00 am. •March, June July and August: the dry bulb temperatures remain within the range of 27oC and 38oC for the second most hours (17 hours) during these 4 months. Together with April and May, these months mark the hottest period of the year in Ho Chi Minh City.

27oC consistently during the 24-hour period of this month.

29


MONTHLY AVERAGE GLOBAL HORIZONTAL RADIATION DISTRIBUTION BY TIME OF DAY From December to February where temperature conditions fall within the range of 0oC and 21oC, take advantage of solar heat gain.

From December to February where temperature conditions fall within the range of 0oC and 21oC, take advantage of solar heat gain.

Sunrise

00:00

00:00

00:00

02:00

02:00

02:00

04:00

04:00

04:00

06:00

Sunset

Sunrise

06:00

In general, between 9:00 and 15:00 from April to December, Ha Noi has the strongest global horizontal radiation. Based on the dry bulb temperature analysis, it is important to protect the internal spaces of the building from solar exposure during those hours especially from May to October in order to prevent unwanted heat gain caused by the solar radiation.

HA nOI - GLOBAL HORIZONTAL RADIATION

08:00

08:00

10:00

10:00

10:00

12:00

12:00

12:00

14:00

14:00

14:00

16:00

16:00

16:00

18:00

18:00

Sunset

20:00

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Sunset

18:00

20:00

20:00

22:00

22:00

24:00

In general, from January to September, Da Nang has the strongest global radiation. Based on the dry bulb temperature analysis above it is important to protect the internal spaces of the building from solar exposure between 9:00 and 15:00 especially from April to October in order to prevent unwanted heat gain caused by the solar radiation.

DA NANG - Global Horizontal Radiation

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

24:00

In general, between 10:00 and 14:00 from October to August, Ho Chi Minh City has the strongest global horizontal radiation. Based on the dry bulb temperature analysis above it is important, especially in Ho Chi Minh City, to protect the internal spaces of the building from solar exposure during all hours in between sunrise and sunset of the 12 months of the year.

HO CHI MINH CITY -GLOBAL HORIZONTAL RADIATION

Night Time (48%)

316 - 474 Wh/m2 (9%)

Night Time (50%)

316 - 474 Wh/m2 (11%)

Night Time (50%)

316 - 474 Wh/m2 (10%)

4 - 158 Wh/m2 (14%)

> 474 Wh/m2 (15%)

4 - 158 Wh/m2 (10%)

> 474 Wh/m2 (17%)

4 - 158 Wh/m2 (11%)

> 474 Wh/m2 (20%)

158 - 316 Wh/m2 (11%)

30

06:00

08:00

22:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Sunrise

158 - 316 Wh/m2 (10%)

158 - 316 Wh/m2 (7%)


MONTHLY AVERAGE SKY COVER DISTRIBUTION BY TIME OF DAY Ha Noi’s sky remains significantly cloudy throughout the year. This may actually render passive solar heating to be ineffective during the cold months from November to March.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec As indicated above, Ha Noi’s sky remains significantly cloudy throughout the year. With that said, during the hot months from May to October, direct solar radiation should be less of a concern while diffuse solar radiation should be properly dealt with in order to avoid unwanted heat gain.

Da Nang’s sky remains significantly cloudy during the months that require heating. This may actually render passive solar heating to be ineffective 00:00

00:0

00:00

02:00

02:00

02:00

04:00

04:00

04:00

06:00

06:0

06:00

08:00

08:00

08:00

10:00

10:00

10:00

12:00

12:00

12:00

14:00

14:00

14:00

16:00

16:00

16:00

18:00

18:00

18:00

20:00

20:00

20:00

22:00

22:00

22:00

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Da Nang’s sky remains significantly cloudy throughout the year with the exception of May, June, July and August. These months have relatively clear sky. In addition, these 4 months also have high temperatures, therefore it is important to protect the internal spaces of the building from unwanted heat gain caused by both direct and diffuse solar radiation.

HA nOI - SKY COVER

DA NANG - SKY COVER

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ho Chi Minh City’s sky remains significantly cloudy throughout the year, with the exception of January, March, June, July, and December. These months have relatively clear sky. Since these months have high temperatures, therefore it is important to protect the internal spaces of the building from unwanted heat gain caused by both direct and diffuse solar radiation.

HO CHI MINH CITY - SKY COVER

< 10 (0%)

60 - 80 (43%)

< 10 (0%)

60 - 80 (54%)

< 10 (0%)

60 - 80 (57%)

10 - 30 (0%)

> 80 (41%)

10 - 30 (0%)

> 80 (21%)

10 - 30 (0%)

> 80 (5%)

30 - 60 (15%)

30 - 60 (23%)

24:00

30 - 60 (36%)

31


MONTHLY AVERAGE RELATIVE humidity levels BY TIME OF DAY Humidity levels in Ha Noi remain above 80% for 51% of the year. Caution must be taken to avoid adding extra moisture to the internal spaces of the building.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ha Noi has a very small period during the year (3%) where humidity levels fall within the range of 40% and 60%. Even though evaporative cooling may be of some benefit during this period, however it is ineffective and even not feasible for most of the year due to high humidity levels for most of the year.

HA nOI - RELATIVE HUMIDITY

Out of the three cities, Ho Chi Minh City experiences the highest levels of humdity (>80%) least frequently (26%). Avoid adding extra moisture to the internal spaces of the building especially during the dotted red period.

00:00

00:0

00:00

02:00

02:00

02:00

04:00

04:00

04:00

06:00

06:0

06:00

08:00

08:00

08:00

10:00

10:00

10:00

12:00

12:00

12:00

14:00

14:00

14:00

16:00

16:00

16:00

18:00

18:00

18:00

20:00

20:00

20:00

22:00

22:00

22:00

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Out of the three cities, Da Nang experiences the lowest levels of humidity (40% 60%) least frequently, only 2% of the year. Similarly to Ha Noi, practitioners should take caution when considering evaporative cooling strategies as it is ineffective and even not feasible for most of the year.

DA NANG - RELATIVE HUMIDITY

24:00

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Out of the three cities, Ho Chi Minh City experiences low humidity levels most frequently. As indicated in the conditioning square, from December to May, Ho Chi Minh City has a distinctively dry season with humidity levels falling within the range of 40% and 60%. Evaporative Cooling would be of benefit for buildings in Ho Chi Minh City during this period.

HO CHI MINH CITY - RELATIVE HUMIDITY

< 20 (0%)

60 - 80 (40%)

< 20 (0%)

60 - 80 (37%)

< 20 (0%)

60 - 80 (60%)

20 - 40 (0%)

> 80 (51%)

20 - 40 (0%)

> 80 (59%)

20 - 40 (0%)

> 80 (26%)

40 - 60 (3%)

32

Out of the three cities, Da Nang experiences the highest levels of humidty (>80%) most frequently, 59% of the year. Avoid adding extra moisture to the internal spaces.

40 - 60 (2%)

40 - 60 (13%)

24:00


Prevailing wind directions of the 3 cities HA NOI - MONTHLY WIND ROSES hrs

hrs

105+ 94 84 73 63 52 42 31 21 <10

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

131+ 117 104 91 78 65 52 39 26 <13

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

January

February

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

May

30 km/h 20 km/h 10 km/h

72+ 64 57 50 43 36 28 21 14 <7

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

July

September

30 km/h 20 km/h 10 km/h

69+ 62 55 48 41 34 27 20 13 <6

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

October

November

50 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

30° 40 km/h 45°

510 408 306 204 <102

30km/h km/h 30 300°

60° 20km/h km/h 20 75°

10km/h km/h 10

WEST

EAST

255°

105°

240°

120°

225°

135° 210°

150° SOUTH

40 km/h 30 km/h 20 km/h 10 km/h

165°

20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

40 km/h 30 km/h 20 km/h 10 km/h

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

November

50 km/h

45°

213 170 128 85 <42

30 km/h 300°

60° 20 km/h 75°

10 km/h

WEST

EAST

255°

105°

240°

120°

225°

135° 210°

150° 195°

SOUTH

165°

30 km/h 20 km/h 10 km/h

February

40 km/h 30 km/h 20 km/h 10 km/h

52+ 46 41 36 31 26 20 15 10 <5

40 km/h 30 km/h 20 km/h 10 km/h

May

30 km/h 20 km/h 10 km/h

35+ 31 28 24 21 17 14 10 7 <3

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

July

40 km/h 30 km/h 20 km/h 10 km/h

77+ 69 61 53 46 38 30 23 15 <7

50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

October

November

50 km/h

40 km/h 315°

December - March East (E) May - September South (S)

20 km/h 10 km/h

hrs 50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

77+ 69 61 53 46 38 30 23 15 <7

hrs 50 km/h 40 km/h 30 km/h 20 km/h 10 km/h

118+ 106 94 82 70 59 47 35 23 <11

hrs

30° 45°

306 244 183 122 <61

30 km/h 300°

60° 20 km/h

285°

30 km/h

39+ 35 31 27 23 19 15 11 7 <3

612+ 550 489 428 367

15°

330°

Annual Wind Rose

40 km/h

December

NORTH 345°

hrs 50 km/h

hrs

70+ 62 56 48 42 35 28 21 14 <7

50 km/h

10 km/h

September

August

hrs

66+ 59 52 46 39 33 26 19 13 <6

20 km/h

hrs

52+ 46 41 36 31 26 20 15 10 <5

40 km/h

30 km/h

52+ 46 41 36 31 26 20 15 10 <5

June

hrs 50 km/h

40 km/h

March

50 km/h

April

66+ 59 52 46 39 33 26 19 13 <6

hrs 50 km/h

hrs

38+ 34 30 26 22 19 15 11 7 <3

50 km/h

hrs

30°

40 km/h

hrs

65+ 58 52 45 39 32 26 19 13 <6

427+ 384 341 298 256

15°

58+ 52 46 40 34 29 23 17 11 <5

50 km/h

January

December

40 km/h

285°

10 km/h

hrs

52+ 46 41 36 31 26 20 15 10 <5

50 km/h

October

20 km/h

hrs 50 km/h

hrs

48+ 43 38 33 28 24 19 14 9 <4

30 km/h

September

hrs 50 km/h

330°

South-East (SE)

20 km/h

August

315°

March - September

30 km/h

51+ 45 40 35 30 25 20 15 10 <5

50 km/h

July

40 km/h

June

NORTH

North-East (NE)

40 km/h

hrs

174+ 156 139 121 104 87 69 52 34 <17

50 km/h

hrs 50 km/h

hrs

88+ 79 70 61 52 44 35 26 17 <8

345°

November - February

10 km/h

52+ 46 41 36 31 26 20 15 10 <5

hrs

Annual Wind Rose

20 km/h

May

50 km/h

81+ 72 64 56 48 40 32 24 16 <8

30 km/h

hrs

53+ 47 42 37 31 26 21 15 10 <5

March

50 km/h

April

76+ 68 60 53 45 38 30 22 15 <7

40 km/h

hrs

35+ 31 28 24 21 17 14 10 7 <3

50 km/h

hrs 50 km/h

30 km/h

50 km/h

February

hrs 50 km/h

40 km/h

hrs

171+ 153 136 119 102 85 68 51 34 <17

hrs

65+ 58 52 45 39 32 26 19 13 <6

50 km/h

January

hrs

330°

195°

10 km/h

1021+ 918 816 714 612

15°

315°

285°

20 km/h

December

NORTH 345°

30 km/h

hrs

50 km/h

hrs

80+ 71 64 55 48 40 32 24 16 <8

40 km/h

10 km/h

40 km/h

HO CHI MINH CITY - MONTHLY WIND ROSES

hrs

100+ 89 80 69 60 50 40 30 20 <10

50 km/h

August

hrs 50 km/h

20 km/h

hrs

68+ 61 54 47 40 34 27 20 13 <6

40 km/h

30 km/h

118+ 106 94 82 70 59 47 35 23 <11

June

hrs 50 km/h

40 km/h

hrs

125+ 112 100 87 75 62 50 37 25 <12

50 km/h

April

hrs

hrs 50 km/h

March

hrs

158+ 142 126 110 94 79 63 47 31 <15

50 km/h

DA NANG - MONTHLY WIND ROSES

75°

10 km/h

WEST

EAST

255°

105°

240°

120°

225°

Annual Wind Rose November - April North-West (NW) May - October South-West (SW)

135° 210°

150° 195°

SOUTH

165°

33


CLIMATE-RESPONSIVE DESIGN STRATEGIES based on climate assessment of the 3 cities Month

Maximum Average Wind Speed

Month

Prevailing Wind Directions

Maximum Average Wind Speed

Month January

January

North East

NE

20 km/h

January

North East

NE

10 km/h

February

North East

NE

15 km/h

February

East

E

10 km/h

March

South East

SE

15 km/h

March

East

E

10 km/h

April

South East

SE

15 km/h

North East

NE

10 km/h

May

South East

SE

20 km/h

South West

SW

10 km/h

May

South East

SE

15 km/h

June

South West

SW

10 km/h

South East

SE

10 km/h

South West

SW

10 km/h

April

Prevailing Wind Directions

Maximum Average Wind Speed

North West

NW

10 km/h

North West

NW

10 km/h

West

W

10 km/h

March

North West

NW

15 km/h

April

North West

NW

15 km/h

May

South West

SW

10 km/h

June

South West

SW

10 km/h

July

South West

SW

15 km/h

South

S

15 km/h

West

W

15 km/h

February

June

South East

SE

15 km/h

July

South East

SE

10 km/h

August

South East

SE

10 km/h

September

South East

SE

15 km/h

August

South West

SW

15 km/h

South East

SE

15 km/h

September

South East

SE

10 km/h

North East

NE

15 km/h

October

North West

NW

15 km/h

September

South West

SW

10 km/h

November

North East

NE

15 km/h

November

North West

NW

10 km/h

October

South West

SW

10 km/h

December

North East

NE

15 km/h

North East

NE

15 km/h

East

E

15 km/h

November

North West

NW

10 km/h

December

North West

NW

10 km/h

October

34

Prevailing Wind Directions

July

December

August

prevailing wind implication - HA NOI, VIETNAM

prevailing wind implication - DA NANG, VIETNAM

prevailing wind implication - ho chi minh city, VIETNAM

From November to February, Ha Noi’s prevailing wind comes from the North-East (NE) direction with average maximum speed of approximately 16 km/h, whereas from March to September, it comes from the South-East (SE) direction with average maximum speed of approximately 14 km/h.The month of October experiences the prevailing wind coming from both the SE and NE directions at the maximum speed of 15 km/h. As indicated in the psychrometric plot, the months from November to March requires heating; thus it is important to avoid direct exposure to the NE wind from November to February and SE wind during March. In addition, during the months that require cooling, it is important to capitalize on the SE wind for natural ventilation.

From December to March, Da Nang’s prevailing wind comes from the East direction (North East and East) with average maximum wind speed of approximately 11 km/h, whereas from May to September, it comes from South direction (South-West and South-East) with average wind speed of approximately 10 km/h. During the month of April, it is observed that the prevailing wind comes from both the East and South directions, or more specifically North-East (NE) and South-West (SE), with average maximum wind speed of 10 km/h. The 2 months of October and November experience the prevailing wind coming from the North-West direction (NW). As indicated in the psychrometric plot, the months of December, January and February require heating; thus it is important to protect internal spaces from the prevailing winds coming from the East direction. In addition, during the months that require cooling, it is important to capitalize on the prevailing winds that come from the South for natural ventilation.

From November to April, Ho Chi Minh City’s prevailing wind comes from the North-West (NW) direction with average maximum wind speed of approximately 11 km/h, whereas from March to September, it comes from the South-West (SW) direction with average maximum speed of approximately 12 km/h.The 2 months of February and August experience the prevailing wind coming from the West direction at the maximum speed of 12 km/h. As indicated in the psychrometric plot, Ho Chi Minh City is overheated during the 12 months of the year; thus it is important to capture the prevailing winds coming from those aforementioned directions.


SUN MOVEMENT WITH REGARDS TO MONTHLY AVERAGE TEMPERATURE DISTRIBUTION BY TIME OF DAY N

345°

15°

N

345°

330°

30°

330°

315°

45°

300°

60°

15°

330°

30°

315°

30°

315°

45°

300°

1st Jun

N

345°

15°

45°

300°

60°

60°

1st Jun

1st May 285°

75°

1st Jun

1st May 285°

75°

285°

75°

1st May 1st Apr

1st Apr

1st Apr

270°

90°

270°

90°

255° 1st Feb

105°

1st Jan

17

15

16

14

13

12

11

10

9

8

240°

255° 1st Feb 1st Jan

7 120°

225°

105° 17

345°

12

11

10

105°

9

8

7

1st Jan

210°

16

17

15°

345°

330°

30°

315°

45°

300°

8

7

165°

180°

N

345°

15°

330°

30°

30°

315°

45°

300°

45°

300°

60°

60°

1st Jul

1st Jul

1st Aug

1st Aug 75°

9

150°

15°

1st Jul 285°

10

HO CHI MINH CITY - SUN PATH

315°

60°

11

135°

195°

330°

12

210°

DA NANG - SUN PATH N

13

225°

165°

180°

14

120°

150° 195°

15

240°

135°

HA NOI - SUN PATH N

13

225°

165°

180°

14

120°

150° 195°

15

16

255° 1st Feb

240°

135°

210°

90°

1st Mar

1st Mar

1st Mar

270°

285°

75°

285°

75° 1st Aug

1st Sep 1st Sep 270°

90° 1st Oct

1st Sep 270°

90° 1st Oct

270°

90° 1st Oct

1st Nov 105°

255°

17

15

16

14

13

12

11

10

9

8

7

240°

135°

210°

150° 195°

180°

21oC - 27oC

17

16

15

14

12

11

10

27 C - 38 C

8

225°

135°

21oC - 27oC

17

15

14

12

11

10

o

27 C - 38 C

9

8

1st Nov

7

1st Dec 120°

225°

135°

150° 195°

o

13

240°

165°

SUN needed Shading helps Shading Needed 0oC - 21oC

105° 16

210°

150° 180°

255°

1st Dec

7

120°

195°

o

9

240°

165°

o

13

210°

SUN needed Shading helps Shading Needed 0oC - 21oC

255°

1st Dec 120°

225°

1st Nov 105°

180°

165°

SUN needed Shading helps Shading Needed 0oC - 21oC

21oC - 27oC

27oC - 38oC

35


SUN MOVEMENT WITH REGARDS TO MONTHLY AVERAGE TEMPERATURE DISTRIBUTION BY TIME OF DAY

36

SUN PATH PRIOR TO JUNE 21ST

SUN PATH PRIOR TO JUNE 21ST

SUN PATH PRIOR TO JUNE 21ST

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun only during the 3 months of April, May and June. As the sun moves from sunrise to sunset in both May and June, high temperatures (27oC - 38oC) consistently occur; thus it is definitely needed to shade. Direct solar exposure, though experienced in less hours in April, should be kept away from the internal spaces since the temperatures remain within the range of 21oC and 27oC. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 5 months from January to May. Due to the low temperatures (0oC - 21oC) in January and February, direct sun exposure should be taken advantage of from sunrise to sunset. From March to May, since the temperatures remain consistently above 21oC, direct sun needs to kept to the minimum. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from January to June but only from sunrise to 12:00. Similarly to Southern orientation, direct solar exposure should be taken advantage of in January and February, and should be kept to the minimum from March to May. However, since direct sun is only experienced for the early half of the day, shading may only be needed during those hours. Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from January to June but only from 12:00 to sunset. Similarly to Southern orientation, direct solar exposure should be taken advantage of in January and February, and should be kept to the minimum from March to May

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun only during the 3 months of April, May and June. Direct solar exposure is experienced in more hours in Da Nang (8 hours) than in Ha Noi (5 hours). As the sun moves from sunrise to sunset in these 3 months, temperatures remain consistently above 21oC; thus it is needed to keep direct solar exposure to the minimum. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 5 months from January to May. However, it is important to note that in May, direct solar exposure can only be experienced from 10:00 - 13:00. Unlike Ha Noi, as the sun moves from sunrise to sunset during these months, the temperatures remain mostly above 21oC, with the exception to a few early morning hours in January, February and March. Direct solar exposure should be kept to the minimum in this orientation. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from January to June but only from sunrise to 12:00. Similarly to Southern orientation, direct solar exposure should be kept to the minimum from during these 6 months, especially later morning hours from March to June. Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from January to June but only from 12:00 to sunset. Similarly to Southern orientation, direct solar exposure should be kept to the mininum during these 6 months, especially from March to June.

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun from sunrise to sunset in both May and June. Due to Ho Chi Minh Cityâ&#x20AC;&#x2122;s close proximity to the equator, direct solar exposure is experienced from sunrise to sunset in May. As the sun moves from sunrise to sunset in these 3 months, temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC; thus it is needed to keep direct solar exposure to the minimal. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 4 months from January to April. As the sun moves from sunrise to sunset in these 4 months, temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC; thus it is needed to keep direct solar exposure to the minimal. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from January to June but only from sunrise to 12:00. Similarly to Southern orientation, direct solar exposure should be kept to the minimal from January to April because temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC. However, since direct sun is only experienced for the early half of the day, shading may only be needed during those hours. Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from January to June but only from 12:00 to sunset. This orientation should be either completely avoided or shaded in Ho Chi Minh City due to the occurrence of high temperatures (27oC - 38oC) at all hours in the 6 months.

SUN PATH AFTER JUNE 21ST

SUN PATH AFTER JUNE 21ST

SUN PATH AFTER JUNE 21ST

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun only during the 3 months of July, August and September. As the sun moves East to West in these months, high temperatures (27oC - 38oC) frequently occur; thus it is definitely needed to shade. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 5 months from August to December. From March to May, since the temperatures remain consistently above 21oC, direct sun needs to kept to the minimum. A small percentage of December experiences low temperatures (0oC - 27oC); thus solar heat gain may be beneficial for these hours. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from July to December but only from sunrise to 12:00. Direct solar exposure should be kept to the minimum during these months because temperatures remain consistently above 21oC. A few hours in December may benefit from solar heat gain. Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from January to June but only from 12:00 to sunset. Direct solar exposure should be kept to the minimum during these months because temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC. A few hours in December may benefit from solar heat gain.

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun only during the 3 months of July, August and September. Direct solar exposure is experienced in more hours in Da Nang (8 hours) than in Ha Noi (5 hours). As the sun moves from sunrise to sunset in these 3 months, high temperatures (27oC - 38oC) frequently occur; thus it is needed to keep direct solar exposure to the minimum. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 5 months from August to December. However, it is important to note that in August, direct solar exposure can only be experienced from 10:00 - 13:00. As the sun moves from sunrise to sunset during these months, the temperatures remain mostly above 21oC, with the exception to a few early morning hours in December. Direct solar exposure should be kept to the minimum in this orientation. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from July to December but only from sunrise to 12:00. Direct solar exposure should be kept to the minimum during these 6 months because temperatures remain consistently above 21oC Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from July to December but only from 12:00 to sunset. Direct solar exposure should be kept to the minimum during these 6 months because temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC

Northern Orientation: Buildings whose facade faces North are exposed to the direct sun from sunrise to sunset in both July and August. Due to Ho Chi Minh Cityâ&#x20AC;&#x2122;s close proximity to the equator, direct solar exposure is experienced from sunrise to sunset in August. As the sun moves from sunrise to sunset in these 3 months, temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC; thus it is needed to keep direct solar exposure to the minimum. Southern Orientation: Buildings whose facade faces South are exposed to direct sun during the 4 months from September to December. As the sun moves from sunrise to sunset in these 4 months, temperatures remain consistently above 21oC and mostly within the range of 27oC and 38oC; thus it is needed to keep direct solar exposure to the minimum. Eastern Orientation: Buildings whose facade faces East are exposed to direct sun during the 6 months from July to December but only from sunrise to 12:00. Direct solar exposure should be kept to the minimal from January to April because temperatures remain consistently above 21oC. Western Orientation: Buildings whose facade faces West are exposed to direct sun during the 6 months from July to December but only from 12:00 to sunset. This orientation should be either completely avoided or shaded in Ho Chi Minh City due to the occurrence of high temperatures (27oC - 38oC) at all hours in the 6 months.


COINCIDENT TEMPERATURE & HUMIDITY ON A PSYCHROMETRIC CHART Ha Noi: 21.2oN, 105.79oE

Da Nang: 16.07oN, 108.23oE

Ho Chi Minh City: 10.75oN, 106.67oE

Data Points: 1st January to 31st December

Data Points: 1st January to 31st December

Data Points: 1st January to 31st December

Average Monthly 2-hour Data Plots

Average Monthly 2-hour Data Plots

Average Monthly 2-hour Data Plots

Adaptive Thermal Comfort

Adaptive Thermal Comfort

Adaptive Thermal Comfort

January February March April

May June July August

September October November December

January February March April

May June July August

AH

September October November December

January February March April

May June July August

30

30

Hottest Period with Little Diurnal Swing

Humidity Levels Swing from May to August

Very High Levels of Humidity

Extremely High Levels of Humidity

Period with Notably Low Temperatures

Significant Diurnal Swing

Large Fluctuation in Humidity Levels

25

Plenty of Adaptive Comfort Hours

20

20

25DBT(째C)

305

3510

15 40

20 45

20

15

15

10

10 Comfort 5

5

15

25

Significantly Large Diurnal Swing

Comfort

Comfort

AH

September October November December

25DBT(째C) 50

305

35 10

40 15

45 20

50 25

30

35

37


MONTHLY AVERAGE SKY COVER DISTRIBUTION BY TIME OF DAY OBSERVATIONS

OBSERVATIONS

The psychrometric plot of Ha Noi indicates both heating and cooling

The psychrometric plot of Da Nang indicates both heating and cooling

Ho Chi Minh City’s temperature and conditions throughout the year

needs. The temperature and humidity conditions of Ha Noi throughout the

needs. The temperature and humidity conditions of Da Nang mostly fall

mostly fall within the prescribed comfort zone, with the exception of those

year fall outside of the prescribed comfort zone except for the month of

outside of the prescribed comfort zone. The months of December, January and February appear to be underheated (below 20oC) most notably during

early morning and early afternoon hours. However, this particular comfort zone assumes not only light breezes to be present but also the occupants to

those early morning hours, whereas May, June, July and August are overheated

be proactively adapting to the thermal conditions of their context. With that

should be protected from both low and high outdoor temperatures when it’s

with temperature peak reaching approximately 33.1oC. With that said, the

said, it is clear on the psychrometric plot that Ho Chi Minh City is of

thermally uncomfortable.

building should be protected from both low and high outdoor temperatures when it’s thermally uncomfortable. Climatic elements such as sun and wind need to be taken into account carefully. Overall, humidity levels in Da Nang are the highest out of the 3 studied cities. This is mainly because of Da Nang’s adjacency to the East Sea. Humidity levels remain consistently above 70% from September to April. The months from May to August have the greatest fluctuation in humidity level out of the 12 months (91% - 51%).With that said, it is generally a good idea to avoid creating additional humidity within the building during the humid

cooling-dominated climate. All of the 12 months appear to be overheated, with the highest average temperature reaching approximately 34.2oC. The building should be protected from high outdoor temperatures when it’s too hot for comfort. Climatic elements such as sun need to be strategically dealt with to avoid overheating. Humidity levels in Ho Chi Minh City fluctuate during the day throughout the 12 months of the year but most notably from December to May (48% - 91%). With that said, it is generally a good idea to avoid creating additional humidity within the building during the humid months from April to November.

months from September to April. Dehumidification strategies would also greatly benefit the occupant’s thermal comfort during these months. During the months from May to August when the humidity levels remain comparatively low, evaporative cooling may be effective in reducing needs for

Dehumidification strategies would also greatly benefit the occupant’s thermal comfort during these months. During the months from December to May when the humidity levels remain comparatively low, evaporative cooling

October. The months from November to March are underheated whereas June, July and August appear to be overheated. With that said, the building

In addition, climatic elements such as sun and wind need to be taken into account carefully in order to appropriately accommodate both the respective heating and cooling needs during those months. The month of October has the nicest humidity and temperature conditions since it falls completely within the comfort zone. However, occupant’s thermal sailing and light breezes must occur in order for this month to be thermally comfortable. Humidity levels in Ha Noi remain high throughout the year except for the months from October to December; thus it is generally a good idea to avoid creating additional humidity within the building. Dehumidification strategies would greatly benefit the occupant’s thermal comfort. Humidity levels in almost half of the hours during the months from October to December fall below 70%, thus evaporative cooling may be effective to reduce mechanical cooling during these months. The diurnal swings appear to not be significant enough for strategies such as thermal mass and night cooling to be feasible.

mechanical cooling. In addition, the diurnal swings appear to only occur accross the comfort zone during these months, which may suggest the feasibility of strategies such as thermal mass and night cooling.

38

OBSERVATIONS

may be effective in reducing needs for mechanical cooling. In addition the diurnal swings occur across the comfort zone during the 12 months of the year, which may suggest the feasibility of strategies such as thermal mass and night cooling.


CLIMATIC ELEMENTS ARE PRIORITIZED BASED ON CLIMATE ASSESSMENT OF THE 3 CITIES

Tropical Monsoon Climate (Am)

Humid Subtropical Climate (Cwa)

CLIMATE-RESPONSIVE DESIGN PRIORITIES Climatic Liabilities

Climatic Assets

CLIMATE-RESPONSIVE DESIGN PRIORITIES Climatic Liabilities

Climatic Assets

Tropical Wet & Dry Climate (Aw)

CLIMATE-RESPONSIVE DESIGN PRIORITIES Climatic Liabilities

Climatic Assets

39


DESIGN RECOMMENDATIONS (HA NOI) 1. BLOCK Moisture

DESIGN RECOMMENDATIONS (DA NANG) 1. BLOCK Moisture

Avoid creating additional moisture to the internal spaces of the building

Avoid creating additional moisture to the internal spaces of the building

Occupants should adjust their thermal comfort via clothing choices and activity levels

2. BLOCK HIGH TEMPERATURES

2. BLOCK HIGH TEMPERATURES

2. BLOCK HIGH TEMPERATURES

Protect against high outdoor temperatures when it is too hot for comfort

Protect against high outdoor temperatures when it is too hot for comfort

Protect against high outdoor temperatures when it is too hot for comfort

3. BLOCK INTENSE SUN

3. BLOCK INTENSE SUN

3. BLOCK INTENSE SUN

Keep out the sun when it is too hot for comfort to avoid overheating

Keep out the sun when it is too hot for comfort to avoid overheating

Keep out the sun when it is too hot for comfort to avoid overheating

4. TAKE ADVANTAGE OF SOUTH EAST wind

4. TAKE ADVANTAGE OF SOUTHERN windS

4. BLOCK Moisture

Allow for cooling via natural ventilation when it is too hot for comfort

Allow for cooling via natural ventilation when it is too hot for comfort

Avoid creating additional moisture to the internal spaces of the building

5. BLOCK LOW TEMPERATURES

5. Take advantage of DIURNAL SWING

5. TAKE ADVANTAGE OF wind

Avoid exposure to low outside temperatures when it is too cool for comfort

Flatten out day-to-night temperature swings to ensure thermal comfort

Allow for cooling via natural ventilation when it is too hot for comfort

6. BLOCK NORTH EAST WIND

6. block low TEMPERATUREs

6. TAKE ADVANTAGE OF DIURNAL SWING

Protect from cold winter winds while allowing for summer ventilation

Avoid exposure to low outside temperatures when it is too cool for comfort

Flatten out day-to-night temperature swings to ensure thermal comfort

7. CAREFULLY ALLOW THE SUN INSIDE

7. block EASTERN WINDS

7. CAREFULLY ADD MOISTURE

Allow for sunlight to enter the building when it is too cool for comfort

Protect from cold winter winds while allowing for summer ventilation

Use natural ventilation combined with moisture addition when it is hot and dry

8. ADAPTIVE COMFORT MAY BE OF BENEFIT

8. CAREFULLY ALLOW THE sun INSIDE

S. ALLOW FOR NATURAL DAYLIGHT

Occupants should adjust their thermal comfort via clothing choices and activity levels

Allow for sunlight to enter the building when it is too cool for comfort

Protect the building from unwanted solar heat gain while allowing for natural daylight

S. ALLOW FOR NATURAL DAYLIGHT

9. ADAPTIVE COMFORT MAY BE OF BENEFIT

Protect the building from unwanted solar heat gain while allowing for natural daylight

Occupants should adjust their thermal comfort via clothing choices and activity levels

S. ALLOW FOR NATURAL DAYLIGHT Protect the building from unwanted solar heat gain while allowing for natural daylight

40

DESIGN RECOMMENDATIONS (HO CHI MINH CITY) 1. ADAPTIVE COMFORT is a must


4. Climate Responsive Design Strategies

41


a. Solar Control

42


In order to effectively mitigate the negative impact of solar heat gain, most optimal sun shading devices must be used N

345°

15°

N

345°

330°

30°

15°

330°

N

345°

30°

15° 30°

330° 315°

45°

315°

300°

60°

300°

1st Jul

45°

60°

1st Aug

1st May 285°

75°

1st Jul

1st Jun

75°

285° 1st May

1st Sep

1st Sep

60°

300°

1st Jul

1st Jun

1st Aug

1st May 285°

1st Apr

Overview

45° 315°

1st Jun

75° 1st Aug

1st Apr 1st Apr

1st Oct 345°

1st Mar

345°

15°

255° 1st Feb

330°

1st Jan 315°

15

16

17

300°

12

13

14

11

45°

240°

9

8

1st Mar

15°

345° 30°

330°

1st May 285°

195°

1st Aug

150°

75°

165°

180°

Building Block (HA NOI)

345°

1st Mar

90° 1st Oct N 1st Mar 1st Nov 255°105° 1st Feb

330°

255° 1st Feb 1st Jan

17

15

16

14

11 315°10

12

13

9

8

Jan 1st1st Dec

7

240°

120°

90° 1st Oct 15° 1st Nov 105°

30°

45° 14

15

16

17

10

9

8

7

1st Dec 120°

225°

135°

135°

1st Jul

195°

75°

210°

150°

195°

165°

150° 165°

1st Sep

1st Apr

10

9

8

1st Mar

15° 30°

1st Apr

1st Aug

150°

Building Block (DA NANG) 180° 1st Sep

75°

165°

90° 1st Oct N 1st Mar

1st Sep

270°

1st Mar

345° 330°

255° 1st Feb 1st Jan

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

17

16

15

12

13

14

11

10 315°

9

8

7

240°

90° 1st Oct 15° 1st Nov 105°

30° 15

16

17

14

13

45°

12

11

10

9

8

1st Dec

7

225°

255° 1st Feb 1st Jan

15

16

17

14

13

12

11

10

9

8

7

240°

195°

1st Apr

195°

75°

165°

270°

1st Dec 120°

345°

1st Sep

255° 1st Feb 17

16

15

14

12

13

11

10

9

8

90° 15°

1st Oct 30°

255° 105° 1st Feb 1st Nov

7

315°

1st Sep

90°

N 1st Mar 1st Oct

330°

75° 1st Aug

165°

1st Jan 1st Dec 120° 240°

105°

1st Sep

195°

165°

1st Nov 105°

255° 1st Feb

1st Dec

16

17

1st Jan

15

14

13

12

11

10

9

8

1st Dec

7

240°

225°

75° 1st Aug

165°

150° 165°

195° 1st Sep

1st Oct 105°

255° 1st Feb 17

1st Jan

16

15

14

13

12

11

10

9

8

1st Nov

7

1st Dec 120°

135°

150° 195°

HSA = 65o

135°

1st Jul

210°

225°

Size vertical fins at a cut off angle of 65o

1st Nov

7

135°

210°

Avoid West Orientation if possible. If not possible, use “scrim”, dynamic vertical fins or overhang

8

60° 135°

150°

1st Mar

120°

225°

WEST

9

1st Dec 120°

1st Apr

165°

NORTH

10

45°

300° 1st Jun 285° 1st May

210° 195°

150° 180°

11

13

14

15

16

17

240°

195°

60°

150°

1st Oct

135°

210°

45°

135°

Building Block (Ho Chi Minh city) 270°

1st Mar

150°

1st Mar

120°

225°

30°

1st Nov

7

1st Jul

285° 75° 1st May 1st Aug 180°

1st Apr

225°

1st Aug 210°

1st Apr

1st Nov 105°

105° 8

1st Jul 1st Jun 210°

285° 1st May

135°

1st Jul

150°

1st Oct 1st Mar

330°

60° 135°

1st Jun 1st May 285°

210°

9

60° 300°

225°

120°

300°

10 315°

1st Jun

1st Jan

120° 240°

225°

11

45°

1st Apr

270°

12

13

14

240°

300°

1st Jul

1st Aug 1st May 285° 75°

210°

30° 15

60°

135°

1st 1stJul Jun

1st Jun 1st May 285°

16

17

1st Jan 315°

15°

345°

255° 1st Feb

45°

120°

60° 300°

15°

330°

1st Dec

7

315°

1st Oct

345°

240°

1st Aug

1st May 285°

210°

11

11

45°

225°

60°

1st Jun

225°

12

13

240°

300°

1st Nov 105°

330° 12

13

14

1st Sep

270°

270°

15

195°

1st Apr 1st Sep

1st Apr

30° 16

240°

300°

1st Jul

Aug 1st1st May 285°75°

210°

315°

60°

135°

345°

17

1st Jan

45°

120°

1st 1st JulJun

1st Jun

15° 255° 1st Feb

1st Dec

7

300°

60°

225°

10 315°

1st Sep

1st Oct

1st Nov 105°

330°

30°

sun shading devices

180°

195°

NORTH

WEST

Size vertical fins at a cut off angle of 65o along & a horizontal overhang with a cut off angle of 80.2o HSA = 65o

150°

210°

165°

Avoid West Orientation if possible. If not possible, use “scrim”, dynamic vertical fins or overhang

NORTH

WEST

Size a single vertical fin o at a cut off angle of 65 & a horizontal overhang with a cut off angle of 60o HSA = 65o

VSA = 82o

180°

165°

Avoid West Orientation if possible. If not possible, use “scrim”, dynamic vertical fins or overhang

Vietnam is exposed to plenty of solar radiation, which, if not handled carefully, can easily exacerbate the thermal stress on building’s occupants. With that said, it is important that practitioners in Vietnam and other countries of similar climatic conditions try to eliminate unwanted solar heat gain, which would in turn reduce the overall energy consumption for space cooling. Amongst all the solar control strategies known to practitioners today such as radiation intercepting glass, sun-shading devices provide the most efficient performance, while remaining competitively cost-effective. Victor Olgyay, in his argument for the use of sun shading devices, suggested, “Heat radiation is most efficiently halted before it reaches the building envelope proper” (Olgyay, 1992). However, in order to maximize the effectiveness of these devices, it is important to take into account these 3 following factors: • Influence of color, and material • Location of shade protection • Effectiveness of various shading methods

VSA = 60o

Shading Device Types AVOID!

Although there are many different kinds of shading device used in buildings today, there are three basic types of shading devices: • Horizontal (Overhang) • Vertical Fin • Egg Crate (Combined)

AVOID!

AVOID!

Vertical Fins

Egg Crate

Overhang + Single Vertical Fin

Overhang + Single Vertical Fin

Overhang

Overhang + Single Vertical Fin

AVOID!

HSA = 80o

VSA = 65o

Size a single vertical fin at a cut off angle of 80o & a horizontal overhang with a cut off angle of 65o

SOUTH

HSA = 75o

Avoid West Orientation if possible. If not possible, use “scrim”, dynamic vertical fins or overhang

EAST

HA NOI - OPTIMAL SHADING MASKS

Size a single vertical fin at a cut off angle of 75o & a horizontal overhang with a cut off angle of 60o

SOUTH

VSA = 60o

VSA = 10o

Size horizontal overhang at cut off angle of 10o

EAST

DA NANG - OPTIMAL SHADING MASKS

HSA = 50o

Size a single vertical fin at a cut off angle of 50o & a horizontal overhang with a cut off angle of 50o

SOUTH

VSA = 50o

VSA = 15o

Size horizontal overhang at cut off angle of 15o

EAST

Horizontal Overhang

Vertical Fins

Egg Crate

HO CHI MINH CITY - OPTIMAL SHADING MASKS

43


HO CHI MINH CITY Number of Fins

2

Number of Fins

1

Cut-off Angle

65o

Cut-off Angle

65o

Cut-off Angle

65o

Position to Glass

Exterior

Position to Glass

Exterior

Position to Glass

Exterior

Surface Color

Refl ective

Surface Color

Refl ective

Surface Color

Refl ective

Overhang (Y/N)

No (N)

Overhang (Y/N)

Yes (Y)

Overhang (Y/N)

Yes (Y)

Notes: • A overhang needs to be added to achieve optimal shading. • Consider view, privacy, rain protection and air movement.

SOUTH

Number of Fins

1

Number of Fins

1

80o

Cut-off Angle

75o

Cut-off Angle

50o

Exterior

Surface Color

Refl ective

Overhang (Y/N)

Yes (Y)

Notes: • An overhang needs to be added to achieve optimal shading. • Consider view, privacy, rain protection and air movement.

Position to Glass

Exterior

Surface Color

Refl ective

Overhang (Y/N)

Yes (Y)

Notes: • An overhang needs to be added to achieve optimal shading. • Consider view, privacy, rain protection and air movement.

Window glazing

Exterior

Surface Color

Refl ective

Overhang (Y/N)

Yes (Y)

In the context of the three studied Vietnamese cities, vertical fins are most applicable in the Northern orientation. The Southern orientation can also benefit from this type of shading devices, however with less density than the North. Window areas on the East and West can benefit from vertical fins that are closely spaced as they eliminate acute sun while still allowing for air movement and some view.

Different Types of Vertical Fin Application

Notes: • A overhang needs to be added to achieve optimal shading. • Consider view, privacy, rain protection and air movement.

Interior

Exterior

Window glazing

Position to Glass

Applicability

Image 1. DA&A House

(http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html)

Image 2. 3x9 House

(http://www.archdaily.com/223340/3x9-house-a21-studio/)

Image 3. A21 House

Image 4. Binh Duong School

(http://www.archdaily.com/246049/a21house-a21-studio/)

HA NOI

(http://www.archdaily.com/199688/binh-duong-school-vo-trong-nghia/)

WEST Notes: Consider view, privacy, rain protection and air movement. “Scrim” and operable vertical fins would be effective if this orientation cannot be avoided in an urban area.

Device Type “Scrim” or operable vertical fins Exterior

Device Type

Exterior

Notes: Consider view, privacy, rain protection and air movement. “Scrim” and operable vertical fins would be effective if this orientation cannot be avoided in an urban area.

Device Type “Scrim” or operable vertical fins Position to Glass

Exterior

Interior

Image 7. Le Mon House

(http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/)

Image 8. Operable Sun Louvers (http://www.archdaily.com/12751/villa-old-oaks-ofis-arhitekti/)

Image 9. Vietnam Pavilion

(http://www.littlegirltravels.com/2011/05/14/shanghai-world-expo-2010/)

Image 10. Bamboo Vertical “Scrim” (http://baonoithat.com/Nha-hang-Gio-va-Nuoc-tai-TP-HCM.aspx)

Image 11. Canada Pavilion

(http://www.littlegirltravels.com/2011/05/14/shanghai-world-expo-2010/)

Image 12. Wind & Water Cafe (http://ashui.com/mag/images/stories/200812/gionuoc3.jpg)

Operable Vertical Fins Privacy

44

Air Porosity

Light Porosity

Rain Protection

Angled Vertical Fins

WEST

“Scrim” or operablevertical fins Position to Glass

Regular Vertical Fins

Exterior

Position to Glass

Image 6. I Resort

(http://www.archdaily.com/214626/i-resort-a21-studio-2/)

HO CHI MINH CITY

DA NANG EAST + WEST

Notes: Consider view, privacy, rain protection and air movement. “Scrim” and operable vertical fins would be effective if this orientation cannot be avoided in an urban area.

Image 5. Lam Cafe

(http://www.archdaily.com/196756/lam-cafe-a21-studio/)

These qualities have 3 different ratings: High (H), Medium (M), Low (L)

Exterior

Position to Glass

Exterior

1

Cut-off Angle

Exterior

Number of Fins

Vertical Fins

Exterior

Window glazing

SOUTH

Interior

Interior

Exterior

SOUTH

Interior

Notes: • A slight overhang needs to be added to achieve optimal shading. • Consider view, privacy, rain protection and air movement.

Window glazing

Exterior

2

Exterior

Number of Fins

Notes: Consider view, privacy, rain protection and air movement.

Window glazing

sun shading devices

NORTH

Interior

Window glazing

NORTH

Interior

Interior

Exterior

NORTH

Interior

DA NANG

Interior

HA NOI

Vertical “Scrim”


HA NOI SOUTH

NORTH & SOUTH o

Image 1. Stacking Green House

Cut-off Angle (North)

80

Cut-off Angle (North)

60 80o

65

Position to Glass

Exterior

Cut-off Angle (South)

60 45oo

Cut-off Angle (South)

50 45oo

Surface Color

Refl ective

Position to Glass

Exterior

Position to Glass

Exterior

Vertical Fins (Y/N)

Yes (Y)

Surface Color

Refl ective

Surface Color

Refl ective

Vertical Fins (Y/N)

Yes (North)

Vertical Fins (Y/N)

Yes (North)

Vertical Fins (Y/N)

Yes (South)

Vertical Fins (Y/N)

Yes (South)

Notes: • A single vertical fin need to be added to achieve optimal shading in the North. • Consider view, privacy, rain protection and air movement.

Notes: • Vertical fins need to be added to achieve optimal shading in the North. • Consider view, privacy, rain protection and air movement.

Notes: • Single fins need to be added to achieve optimal shading in the North and the South • Consider view, privacy, rain protection and air movement.

NORTH

EAST

EAST

Cut-off Angle

10o

Cut-off Angle

15o

Position to Glass

Exterior

Position to Glass

Exterior

Surface Color

Refl ective

Surface Color

Refl ective

Notes: • Since the overhang is deep, slanted horizontal louvers or horizontal “scrim” can be great alternatives • Consider view, privacy, rain protection and air movement.

Image 2. I Resort

Image 3. Nha Beo House

(http://www.archdaily.com/214626/i-resort-a21-studio-2/)

Image 4. Suoi Re Communal House

(http://www.archdaily.com/387096/)

HA NOI

(http://www.archdaily.com/102639/)

Image 7. Retractable Canopy (http://maihiendep.com/shops/Mai-hien-di-dong)

Image 5. MM++ House

(http://www.archdaily.com/240562/house-in-go-vap-mm-architects/)

Notes: Consider view, privacy, rain protection and air movement. “Scrim” and dynamic overhang would be effective if this orientation cannot be avoided in an urban area.

“Scrim” or dynamic overhang Position to Glass

Exterior

Image 8. Passive House

(http://www.archdaily.com/84165/passive-house-karawitz-architecture/)

Privacy

Image 9. J-MT Cultural Center

(http://gegedeversailles.blogspot.com/2010_06_01_archive.html)

Air Porosity

Light Porosity

Horizontal Overhang Applicability In the context of the three studied Vietnamese cities, horizontal overhang is applicable in three cardinal directions: North, South & East. Window areas on the West can benefit from horizontal “scrim” as they eliminate acute sun while still allowing for air movement and some view.

Different Types of Horizontal Overhang Application

Horizontal Overhang

Slanted Horizontal Louvers

Canvas Canopy

Solid/Perforated Strip

Movable Horizontal Louvers

Horizontal “Scrim”

Image 6. M11 House

(http://www.archdaily.com/98450/m11-house-a21-studio/)

HO CHI MINH CITY WEST

Device Type

sun shading devices

Notes: • Since the overhang is deep, slanted horizontal louvers or horizontal “scrim” can be great alternatives • Consider view, privacy, rain protection and air movement.

DA NANG EAST + WEST

Notes: Consider view, privacy, rain protection and air movement. “Scrim” and dynamic overhang would be effective if this orientation cannot be avoided in an urban area.

NORTH & SOUTH o

Cut-off Angle

Not Applicable. See Vertical Fins

(http://www.archdaily.com/199755/stacking-green-vo-trong-nghia/)

HO CHI MINH CITY

DA NANG

WEST

Device Type “Scrim” or dynamic overhang Position to Glass

Exterior

Image 10. Louver Haus

(http://www.archdaily.com/264618/louver-haus-smart-architecture/)

Rain Protection

Notes: Consider view, privacy, rain protection and air movement. “Scrim” and dynamic overhang would be effective if this orientation cannot be avoided in an urban area.

Image 11. Louver House

(http://www.archdaily.com/193108/louver-house-lss/)

Device Type “Scrim” or dynamic overhang Position to Glass

Exterior

Image 12. CAD Louver House (http://www.archdaily.com/144003/)

These qualities have 3 different ratings: High (H), Medium (M), Low (L)

45


whEN THE BUILDING IS ORIENTED TO GET THE MOST EXPOSURE TO PREVAILING WINDS, APPROPRIATE SHADING STRATEGIES MUST BE CAREFULLY IMPLEMENTED N

345°

345°

15°

330°

15°

330°

30°

315°

30°

300° 1st Jun

75°

300°

1st Aug 75° 1st Sep

1st Apr

1st Sep

1st Apr

270°

90° 1st Oct

1st Oct 1st Mar

1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

15

16

240°

14

13

12

11

10

N

345°

9

315° 210° 195°

300°

30°

240°

1st Nov 105°

330°

11

1st Jul 1st Aug

1st May 285°

9

75°

8

1st Dec

7

75° 1st Aug

1st Apr

1st Sep

1st Mar

1st Oct

255° 1st Feb

105°

1st Jan

17

16

15

13

14

12

240°

30°

225°

135° 45°

210°

150°

315°

210°

165°

195°

60°

1st Aug

1st May 285°

75°

9

8

1st Nov

7

1st Dec 120° 15° 30° 135° 45° 150° 165°

180°

300°

1st Jul

1st Jun

10

OR

330°

225°

11

N

345°

300°

60°

1st Jun

10

1st Jul

285° 1st May

15°

195°

165°

60°

1st Jun

120°

N

315°

45°

12

13

14

15

16

345°

135°

150°

OR 17

1st Jan

1st Dec

7

15°

180°

255° 1st Feb

120°

OR

330° 225°

8

45°

1st Jul

1st May 285°

1st Aug

30°

315°

60°

1st Jun

1st Jul

1st May 285°

45°

300°

60°

15°

330°

315°

45°

N

345°

60° 1st Jul

1st Jun 285° 1st May

75° 1st Aug

1st Sep 1st Sep

1st Apr

1st Apr

1st Mar 1st Nov 105°

255° 1st Feb 17

15

16

14

13

12

11

10

9

8

1st Dec

7

240°

120°

210° 180°

16

15

SOUTH-EAST (SE) Size a single vertical fin at a o cut off angle of 50 in addition to a horizontal overhang with a cut off o angle of 33

HA NOI - Prevailing wind directions: north-east & south east

1st Mar

1st Oct

12

11

10

9

8

1st Dec

7

120°

105°

255° 1st Feb 1st Jan

17

16

14

12

11

10

9

225°

210°

150° 195°

EAST

Size horizontal overhang at o a cut off angle of 45

7

Size horizontal overhang at o cut off angle of 10

VSA = 10o

DA NANG - Prevailing wind directions: south & east

1st Nov

135°

165°

SOUTH

8

1st Dec 120°

150°

VSA = 45o

13

240°

135°

180°

15

180°

165°

NORTH-WEST (NW)

SOUTH-WEST (SW) VSA = 55o

Size a single vertical fin at a o cut off angle of 20 in addition to a horizontal overhang with a cut off o angle of 55

ic am yn ice r d ev ”o gd im in cr d “S sha

ic am yn ice r d ev ”o gd im in cr d “S sha

Sin O gl ver e ha Ve n rti g ca + lF in

HSA = 50o

13

240°

195°

VSA = 33o

46

17

165°

NORTH-EAST (NE) This orientation is exposed to intense sun. If not possible, use “scrim”, dynamic vertical fins or overhang

1st Jan

14

210°

150° 195°

255° 1st Feb

225°

135°

225°

1st Nov 105°

Sin O gl ver e ha Ve n rti g ca + lF in

1st Jan

1st Sep

1st Oct

1st Oct 1st Mar

1st Apr

This orientation is exposed to intense sun. If not possible, use “scrim”, dynamic vertical fins or overhang

HSA = 20o

HO CHI MINH CITY - prevailing wind directions: north-west & SOUTH WEST


Appropriate shading strategies must also be implemented for the light well to avoid heat gain from the overhead sun

OVERHEAD SHADING

Latitude & Longitude

21.04oN - 105.79oE

Latitude & Longitude

16.06oN - 108.23oE

Latitude & Longitude

10.75oN - 106.67oE

Altitude Angle @ Solar Noon

90o - Latitude +/- Declination

Altitude Angle @ Solar Noon

90o - Latitude +/- Declination

Altitude Angle @ Solar Noon

90o - Latitude +/- Declination

June 21st (Maximum)

92.46o North

June 21st (Maximum)

97.44o North

June 21st (Maximum)

102.75o North

Shading of Vertical Voids

March 21st / September 21st (Equinox)

68.96o North

March 21st / September 21st (Equinox)

73.94o North

March 21st / September 21st (Equinox)

79.25o North

Applicability

st

December 21 (Minimum)

45.46o North

50.44o

st

December 21 (Minimum)

North

55.75o

st

December 21 (Minimum)

North

Skylights, open courtyard, light wells and atria are effective means to invite daylight from above inside the building; thus they significantly reduce electric lighting load. However, these spaces need to be shaded well in order to avoid unwanted solar heat gain from the sun above. A variety of strategies can be implemented in the 3 studied cities to prevent overheating and to offset its negative impacts on both the occupants, and the building’s energy footprint.

Daylight & Solar Exposure

Floor Plan Orientation

Elongated North-South

Floor Plan Orientation

Elongated North-South

Floor Plan Orientation

Elongated North-South

In the context of the three studied cities, high sun angles are not only an asset but also a liability that practitioners must always take into consideration, especially when inserting vertical voids in the building. With that said, daylight and solar exposure must be addressed simultaneously in order to maximize the potentials of the overhead sun. Consequentially, the following elements must be taken into account: • Aspect Ratio (AR) • Daylight Factor (DF) Aspect Ratio (AR)

Aspect ratio for spaces such as open courtyards, light wells and atria is their degree of openness to the sky. The greater the aspect ratio, the more exposed these spaces are to the sky. AR = (Area of the void floor)/(average height of surrounding walls)2 Floor Plan Orientation

Elongated East-West

Floor Plan Orientation

Elongated East-West

Floor Plan Orientation

Elongated East-West

Amongst the 3 cities, Ha Noi is located furthest away from the equator, thus experiencing lowest sun angles. The diagrams above indicate the entrance of sun rays from the overhead sun inside the building via the vertical void during a few hours prior to and after 12:00 pm. However since Ha Noi’s sky remains mostly overcast throughout the year, a glass cover with dynamic shading device should be installed to both take advantage of daylight and avoid unwanted solar heat gain.

Da Nang has higher sun angles than Ha Noi during the year, thus experiencing a longer period of solar exposure throughout the year. With that said, it is necessary for designers in this city to implement dynamic toplight shading strategies to avoid unwanted heat gain while still allowing for the entrance of natural daylight. If solar-induced ventilation is used in the building, spaces that are adjacent to the vertical voids must be carefully shaded & zoned to avoid coincidental overheating.

Amongst the three cities, Ho Chi Minh City experiences the highest solar angles throughout the year; thus the overhead sun becomes both an asset and a liability for the building’s occupants as sun rays are able to penetrate straight down to the building. Vertical voids i.e. skylights, open courtyards, atria are an effective means to get daylight deep into the building from above. However, unwanted solar heat gain must be prevented with the use of appropriate shading devices.

HA NOI

DA NANG

HO CHI MINH CITY

Daylight Factor (DF)

Daylight factor (DF) is a ratio between the amount of daylight on an interior horizontal plane and that on an exterior horizontal plane. Depending on the activities that take place within the void spaces, practitions can identify target daylight factors accordingly. However, since daylight coincides with heat, the climates of Vietnam would be content with lower daylight factors.

47


Dynamic Shades

Image 6. Atrium Shade (http://www.atriumshade.com/skylight-shades.html)

Image 1. Bamboo Skylight Shade

Image 2. Overhead Bamboo Shade

Image 3. Retractable Canvas Shade

Image 4. Retractable Skylight Shade

Image 5. Atrium Shade

Image 6. Operable Top Light Shade

(http://www.shadingsystemsinc.com/skylight-shades.html)

(http://www.shadingsystemsinc.com/skylight-shades.html)

(http://www.man-cua.com/images/MAN+CHE+GIENG+TROI)

(http://www.shadingsystemsinc.com/skylight-shades.html)

(http://www.atriumshade.com/skylight-shades.html)

(http://www.atriumshade.com/skylight-shades.html)

Dynamic shading devices such as retractable shades are especially effective in the three climates of Vietnam. They provide building’s occupants with the ability to control whether sunlight is welcomed inside or not. These dynamic shades are made from a variety of materials with a variety of colors. Depending on the desired illumination and activities taken place within the light well, colors, materials and control mechanisms can be selected accordingly.

Overhead Slatted Shades

Image 7. Wood Slatted Shade

Image 8. Wood Slatted Shade

Image 9. Deep Overhead Purlin

Image 10. Bamboo Slatted Shade

Image 11. Overhead Slats

Image 12. Overhead Slats

(http://www.archdaily.com/98450/m11-house-a21-studio/)

(www.archdaily.com/282405/the-pool-shophouse-farm/)

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects)

(www.archdaily.com/102639/suoi-re-village-community-house-kiến-việt/)

(http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/167835/Gieng-troi.html)

(http://landtoday.net/vn/khampha/phongthuy/29412)

Vegetation: Vines, Rooted Shrubs & Trees

48

Low-E Glass Top Cover

Plastic (Polycarbonate) Top Cover

Image 13. The Nest House

Image 15. Nha Beo House

Image 17. Retractable Glass Cover

Image 19. Pyramidal Glass Cover

Image 21. Solar Attic

Image 23. Polycarbonate Roof

(http://polycarbonatesheet.co.in/photo_gallery)

(http://www.archdaily.com/387096/)

(http://polycarbonatesheet.co.in/photo_gallery)

(http://hoanggiaglass.com.vn/ung-dung/)

(http://www.iwilltry.org/b/projects/solar-attic/)

(http://www.insu.co.uk/conservatory-upgrades/)

Image 14. A21 House

Image 16. Vegetated Light Well

Image 18. Glass Roof

Image 20. Low-E Glass

Image 22. Colored Polycarbonate

Image 24. Insu Solar Inserts

(http://www.archdaily.com/246049/a21house-a21-studio/)

(http://www.nytimes.com/2009/12/03)

(http://hoanggiaglass.com.vn/ung-dung/)

(http://clearconceptssd.com/2012/05/what-is-low-e-glass/)

(http://polycarbonatesheet.co.in/photo_gallery)

(http://www.insu.co.uk/conservatory-upgrades/)

Overhead slats are often used as a means to shade the light well. Compared to the dynamic shades, these slats are less effective in providing shade for the internal light well and eliminating unwanted solar heat gain. However, they are effective in reducing glare-related issues that come with the entrance of sunlight from above. Practitioners should have these slats integrated into other shading strategies in order to maximize its overall effectiveness.

Other Types of Shading Means Vegetation: Vines, Rooted Shrubs & Trees Vines, trees & rooted shrubs, if strategically planted, not only enhance the overall aesthetics of the light well but also provide efficient shading for the space. In the climate of Ho Chi Minh City, vegetation cools the space via evapotranspiration during the hot and dry period of the year. However, in the climates of Ha Noi & Da Nang, due to the consistently high humidity levels throughout the year, caution must be taken to avoid adding more moisture to the air while still shading effectively. Glass Top Cover In the case where glass top cover is desired to take full advantage of natural daylight, practitioners must select the glass that has low emissivity. Low-E glass is able to deflect UV and infrared radiation, thus preventing unwanted solar heat gain from occurring. Shading of areas adjacent to the glass top is also necessary to avoid coincidental heat gain. Plastic (Polycarbonate) Top Cover Translucent polycarbonate plastic can be used for the top cover of the light well. Products such as Insu solar inserts are often used to help the plastic reflect solar heat before it reaches the internal spaces. However, polycarbonate cover must be carefully maintained as it can be subjected to mold growth & damage due to rain.


REFLECTIVE COLOR CAN BE USED ON THE EXTERNAL SURFACES TO NEGATE THE EFFECTS OF UNWANTED SOLAR HEAT GAIN Non-vegetated Light Colored Roof (Cool Roof)

Literature Review A research conducted by Givoni and Hoffman in 1968 examined the influence of external color of walls and roofs on the indoor temperature conditions. The findings indicated that the diurnal average of the external surface temperature in white roofs “was lower than the air average, and the ceiling’s minima were lower as the roof was thinner, indicating that the 24-hour longwave radiant loss was greater than the solar energy absorbed in white roofs.” (Givoni, 1994) Additionally, the study revealed that when the test walls were painted white as supposed to gray, the indoor temperature conditions remain lower than the outdoor during most of the daytime hours. In general, the choice of color does not involve

External Surfaces Applicability In the three climates of Vietnam where solar radiation levels remain consistently intense throughout the year, the use of reflective color on building’s external surfaces would effectively maintain the desirable indoor temperature conditions Image 1. Allzone House

Image 2. Stacking Green House

Image 3. Lucky Shop House Extension

(http://www.archdaily.com/105334/shophouse-transformation-allzone/)

(www.archdaily.com/199755/stacking-green-vo-trong-nghia/)

(www.archdaily.com/320233/lucky-shophouse-chang-architects/)

additional cost to the overall construction cost of a building. With that said, a reflective color is an economical climatic control feature that can effectively reduce the building’s cooling loads, especially in the three climates of Vietnam.

Solar Absorptance Solar absorptance is the proportion of total incident solar radiation absorbed by the external surface’s material. It typically correlates to the color of that particular material. The lower the solar absorptance, the more heat the surface reflects. Materials

Solar Absorptance

Optical flat black paint

0.98

Red bricks

0.70

Uncolored concrete

0.65

White gloss paint

0.25

Polished Alum Reflector Sheet

0.12

Image 4. Go Vap House

Image 5. Park House

Image 6. 36BTrd House

(www.archdaily.com/240562/house-in-go-vap-mm-architects/01-351/)

(http://www.archdaily.com/212939/the-park-house-formwerkz-architects/)

(www.archdaily.com/199918/36-btrd-dp-architects/)

Light Colored Facade

Excerpted from Alison G. Kwok, 2007

Solar Refl ectance Index (SRI) Solar Reflectance Index (SRI) is a more commonly used measurement than solar absorptance, as it considers both reflectance and emissivity. SRI is a scale from 0 to 100 with 0 being least reflective (reflectance 0.05, emittance 0.90) & 100 being highly reflective (reflectance 0.80, emittance 0.90). Materials

Solar Reflectance Index

Black acrylic paint

0

Light gravel-surfaced roof

37

Uncolored concrete

19 - 52

White acrylic paint

100

Reflective Roof Membrane

80 - 110

Excerpted from Alison G. Kwok, 2007

Use of relective color

Overview It is a well-known fact that light colors refllect light while dark colors absorb it. Depending on the use of the surface, either as a heat absorber or as a light reflector, colors should be selected and used accordingly. In the climates of Vietnam, direct solar heat gain is a serious concern, as it raises the internal temperature of the building, thus increasing the demand for cooling. With that said, it is necessary for practitioners to use light colors for the external surfaces of the building such as walls & roof. In the case of urban tube houses, since they are wedged in between their neighboring buildings, the façade and the roof should have refllective colors to avoid overheating of the interior spaces. For the roof, color’s influence is at its maximum as the roof is constantly exposed to overhead solar radiation. Baruch Givoni stated in his book on passive and low energy cooling of buildings that “the difference in the maximum external surface temperature between a white roof and a black one in a desert in the summer can be 30 to 40oC.” (Givoni, 1994) For the walls, due to the different solar radiation intensities resulted from different orientations, the impact of surface color on the indoor temperature conditions varies. A western wall is most sensitive to the choice of surface color whereas a northern wall is the least sensitive.

Advantages Image 7. Stacking Green House

Image 8. A21 House

Image 9. M11 House

(www.archdaily.com/199755/stacking-green-vo-trong-nghia/)

(www.archdaily.com/246049/a21house-a21-studio/)

(www.archdaily.com/98450/m11-house-a21-studio/)

• This strategy negates the effects of solar heat gain, thus maintaining desirable interior temperature conditions for building’s occupants and consequentially reducing energy consumed for cooling. • This strategy reduces the negative impacts of urban heat island effect on urban dwellers.

Challenges & Limitations Over time, the external surfaces can accumulate dirt; thus practitioners should employ anti-dust light-colored paint, if possible. Image 10. NhaBeo House

Image 11. FARM Shop House

Image 12. The Nest House

(www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/)

(www.archdaily.com/282405/the-pool-shophouse-farm/)

(www.archdaily.com/381335/the-nest-a21studio/)

49


b. Natural Ventilation

The principles of natural ventilation have been known and applied largely

across cultures for centuries. The need to maintain air movement around the human body to evaporate perspiration for cooling relief has been met with the aid of simple devices such as “hand-held fans of yesterday to the mechanical ventilation systems of today.” (AIA Research Corporation, 1978). Natural ventilation, as traditionally employed in the vernacular, is an excellent alternative to reduce dependence on mechanical cooling, thus reducing building’s overall energy consumption, to achieve thermal comfort and to maintain a desirable indoor environment. However, as compared to mechanical ventilation, it is impossible to guarantee consistent performance from natural ventilation due to the unpredictable nature of numerous driving forces. In addition, in the context of Vietnam, rapid urbanization rate propagates tightly clustered developments with increasing building heights, which negatively impact the percolation of wind through the urban area.This, in turn, exacerbates the gravity of urban heat island effect and ultimately exerts a more intense thermal stress on building’s occupants. Having understood the existing conditions with which many major Vietnamese cities are confronted, it is prudent to identify appropriate design strategies that would ensure effectiveness of natural ventilation.

50


when indoor-outdoor temperature differential & wind movement are favorable, opening a window can help achieve comfort Wing Wall Application

Best

Poor

Poor

NATURAL VENTILATION

Openings On Same Wall

Single-sided Ventilation Applicability Single-sided ventilation is applicable to and commonly used in the three climates of Vietnam. However, it may not be able to adequately cool the interior spaces. With that said, practitioners must carefully consider single-sided ventilation with other ventilation strategies such as stack and cross ventilation.

Overview Openings On Adjacent Walls

Air can be steered by creating localized zones of high and low pressure. A variety of architectural features can be employed to create such zones, thus scooping outside air in the room. Wing walls, amongst features such as casement windows, berms, vegetation and fences, are effective in redirecting outside air inside. A wing wall is a building component that protrudes outward from the surface of the building and is typically located in between 2 openings. Wind pressure difference between the windward and leeward sides of the walls causes the circulation of wind in and out the internal space. Wing walls are especially effective in urban area with low air velocity and unfavorable wind conditions. During the 1960s, Baruch Givoni conducted several wind tunnel experiments to examine the effectiveness of wing walls on single-sided ventilated spaces. His findings indicated “the ventilation flow rate & the mean indoor wind speed were significantly increased in a single-sided ventilated room incorporated with wing walls, compared with that without wing walls.” (Nguyen, 2013) (Givoni, 1969). A study, conducted by Nguyen et al., employed CFD technique to examine the potentials of “ventilation improvement from using wing walls and rearranging external windows of the apartment.” (Nguyen, 2013) The results indicated “the implementation of the wing walls increased the pressure drop between openings to around 1.7 Pa; thereby strongly driving the wind in & out the room. The wing wall is, therefore, very effective in single-sided ventilation.” (Nguyen, 2013) Another study, conducted by Chungloo et al., used a CFD package called PHEONICS 3.5 to carry out a series of 3-dimensional simulations and to provide numerical results on detailed specifications of wing walls, openings and balconies. The findings from this study indicated “wing walls with a width of 2.0 m & 4.0 m & a distance between the openings of 2.0 m & 4.0 m in a wind direction of 30.0 degree to 75.0 degree increase the ventilation significantly.” (Sudaporn Chungloo, 2011) In addition, balconies, if placed in the wind direction of 90.0 degree can increase the overall ventilation rate.

Good

Single-sided ventilation is a dominant ventilation phenomenon that occurs within the building as a result of internal doors, especially bedroom doors being closed to maintain occupants’ privacy. When the indoor & outdoor temperature differentials & wind movement are present, the simple act of opening operable windows and doors is sufficient enough cool the interior spaces. However, this strategy often results in poor airfllow rates rendering it undesirable. However, its effectiveness can be improved “by some modifications on the external windows. The use of wing walls is such a solution for single-side ventilation.” (Nguyen, 2013)

Different wing walls of better and worse effectiveness, on same wall and adjacent walls.

Advantages Single-sided ventilation provides users with more control, allowing them to be proactive in adapting their thermal comfort accordingly to the conditions of outside environment. This, in turn, results in a reduction in energy consumption for cooling in the building.

Challenges & Limitations

Image 1. Wing Wall

Image 2. Operable Panels as Wing Walls

Image 3. Window’s shutters as Wing Walls

(www.wayofthepassivehouse.com)

(http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html)

(http://www.danheller.com/images/Europe/Turkey/Istanbul/TopkapiPalace)

•The volume of air displaced as a result of this strategy is dependent on the size of the openings; thus designers must carefully size them to maximize the effectiveness of single-side ventilation. •In densely populated area, practitioners should employ wing walls to invite as much wind inside as possible. •If possible, practitioners should consider integrating control devices and louver systems into the building façade so that building’s occupants can benefit from wind-driven air exchange most consistently.

Wing wall diagrams adapted from Sun, Wind & Light by G.Z. Brown and Mark DeKay, published by Wiley

51


cROSS VENTILATION VIA PREVAILING WINDS SHOULD BE capitalized to NATURALLY COOL BUILDING'S INTERIOR SPACES Prevailing Winds

Direction(s) NORTH

345°

50 km/h

Prevailing Winds hrs

330°

30° 40 km/h

315°

45° 30km/h km/h 30

300°

60°

345°

30°

315°

75°

WEST

EAST

255°

105°

240°

120°

225°

135° 210°

45° 30 km/h

300°

60°

345°

285°

165°

WEST

EAST

255°

105°

240°

120°

225°

135°

315°

45° 30 km/h

300°

60°

285°

306 244 183 122 <61

75°

10 km/h

WEST

Cross Ventilation Applicability Cross ventilation via prevailing winds provides cooling for building’s occupants in the 3 climates of Vietnam since the annual temperature conditions remain consistently high. However, caution must be taken in urban context to ensure desired performance.

EAST

255°

105°

240°

120°

225°

135° 210°

165°

150° 195°

SOUTH

165°

Prevailing Wind Direction

North-East (NE)

Prevailing Wind Direction

East

Prevailing Wind Direction

North-West (NW)

Prevailing Wind Direction

South-East (SE)

Prevailing Wind Direction

South

Prevailing Wind Direction

South-West (SW)

In order to capitalize on the cooling potential of cross ventilation, practitioners in the city of Ha Noi, if possible, should try to orient the buildings to the following two directions: North-East (NE) & South-East (SE). The North-East (NE) wind occurs during the period between November and February, whereas the South-East (SE) wind is more commonly encountered from March to September.

Because of Da Nang’s adjacency to the East Sea, its prevailing winds most commonly come from the East direction (North-East & East), especially during the period between December & March. From May to September, the prevailing winds come from the South. Practitioners here, if possible, should try to orient the buildings to those two directions so that they could effectively implement cross ventilation strategies & efficiently cool the building.

(See Monthly Wind Pattern in “Climatic Assessment” section for more details) Orientation, if carefully considered, can take advantage of free energy from the sun & wind while significantly reducing the building’s overall energy footprint. In addition, it has a great impact on both thermal and visual comfort of the occupants. With that said, it is important for designers in the climate of Ha Noi to pair shading & orientation. If done right, the building can be naturally cooled via cross ventilation & protected from unwanted solar heat gain. (See “Sun Shading Devices” section for more details)

(See Monthly Wind Pattern in “Climatic Assessment” section for more details) When it is possible to orient the building to the two previously specified directions, shading strategies must be used accordingly. Da Nang experiences high temperature conditions most of the year; thus it is important to prevent unwanted solar heat gain from occurring. Since the building will be most likely sandwiched by its neighboring buildings, the facade needs to be well-shaded yet porous enough to allow for air movement. (See “Sun Shading Devices” section for more details)

Ho Chi Minh City experiences wind most frequently out of the three studied cities. In order to capitalize on the cooling potential of this prominent climatic element, practitioners, if possible, should always try to orient their buildings to the following two directions: North-West (NW) & South-West (SW). The North-West (NW) wind occurs during the period between November & April, whereas the South-West (SW) wind is more common from May to September. (See Monthly Wind Pattern in “Climatic Assessment” section for more details) When it is possible to orient the building to the two previously specified directions, shading strategies must be used accordingly. Unlike the other two cities, the temperature conditions in Ho Chi Minh City remain consistently high; thus solar heat gain needs to be cautiously dealt with. Since the building will be most likely sandwiched by its neighboring buildings, the facade needs to be well-shaded yet porous enough to allow for air movement. (See “Sun Shading Devices” section for more details)

HA NOI

DA NANG

HO CHI MINH CITY

Annual Wind Rose Diagrams generated using Autodesk Ecotect Weather Tool ™, edited & illustrated by Duy Vo

52

30° 40 km/h

150° SOUTH

15°

330°

213 170 128 85 <42

75°

10 km/h

195°

50 km/h

612+ 550 489 428 367

20 km/h

210°

150° SOUTH

NORTH

427+ 384 341 298 256

15°

40 km/h

510 408 306 204 <102

Natural ventilation

Direction(s) hrs

20 km/h

10km/h km/h 10

195°

50 km/h

330°

20km/h km/h 20 285°

Prevailing Winds hrs

NORTH

1021+ 918 816 714 612

15°

Direction(s)

Overview Cross ventilation is a form of natural ventilation that, if used strategically and accordingly to climate conditions, can be an excellent energy efficient alternative to mechanical cooling. It relies solely on the wind pressure to force cool outdoor air to move inside the building via inlets (windows, doors, etc…) while simultaneously forcing warm indoor air to move outside the building via outlets (windows, doors, etc…). The effectiveness of this strategy is a function of these following factors: • Opening size, shape and location • Indoor and outdoor temperature differential • Airflow rate • Wind Speed With that said, it is important for architectural designers to take into account the above factors to devise strategies that would take advantage of seasonal prevailing winds to ensure effectiveness of cross ventilation in the building.

Advantages • This strategy lowers the indoor temperature conditions • The air movement increases perceived comfort range by 2-4oC • It is a great alternative to mechanical cooling, thus reducing energy consumed for cooling of internal spaces.

Challenges & Limitations The effectiveness of this strategy is dependent on wind direction & velocity. In densely populated urban areas where overall air porosity is greatly diminished, practitioners should carefully orient the building & appropriately size the openings. In addition, if windows alone are used for cross ventilation, the building should be thin, with minimal amount of interruption caused internal partitions.


a successfully cross-ventilated building minimizes internal partition & provides for adequate inlet and outlet area Openings’ Placement

Natural ventilation

For most effective ventilation, place inlets low and outlets high. Also, openings should be placed across

Cross Ventilation

from, but not directly opposite, each other.

Image 5. Gia Lai House’s Openings

Image 6. Stacking Green House’s Openings

(www.archdaily.com/98450/m11-house-a21-studio/)

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects/)

(www.archdaily.com/199755/stacking-green-vo-trong-nghia/)

Inlet Area = Outlet Area

Inlet Area < Outlet Area

Openings’ Design & Minimally Partitioned Floor Plan Different opening’s designs affect the effectiveness of ventilation, while open floor plan enhances air movement within the internal spaces.

[4

.5 ]

/s] 8

[3 .

6]

2.7 6[

]

.6]

4[1

2 [0.9

]

Cross Ventilation Cooling Capacity (W/m2)

Image 4. M11 House’s Openings

m

should pair small inlet with larger outlet opening.

10

Openings’ size affects both the amount of air and its speed. To enhance effectiveness, practitioners

4

Openings’ Size

[5.

High & Low Openings

m ph

Low Openings

12

High Openings

cit y

Image 3. 36 BTrd House (www.archdaily.com/199918/36-btrd-dp-architects/)

Ve lo

Image 2. Suoi Re Community House (www.archdaily.com/102639/suoi-re-village-community-house-kiến-việt)

W ind

Image 1. A21 House (www.archdaily.com/246049/a21house-a21-studio)

2 Openings - Opposite Walls Across vs. Directly Across

In the tropical climates of Vietnam, openings play an important role in determining occupant’s thermal comfort as their size, design and location determine the ventilation conditions of the internal spaces. While openings’ size and design directly affect the overall volume of wind-induced air and air fllow rate, openings’ location is important to the distribution of cooling and fresh air evenly accross interior rooms. In order to ensure effective cross ventilation, these three factors must be appropriately addressed in designs. Though desirable to have independent cross ventilation to every individual room the builing, it is difficult in practice to accomplish such goal especially in large apartment buildings or even in townhouse rows. In such cases, it is important to minimize partitions internally in order to enable air to move accross the interior rooms from inlet openings to outlet openings. Also, in the case of unfavorable orientation, proper placement of berms, vegetation and wing walls can enhance the overall air fllow.

Cross Ventilation Cooling Capacity (Btu/hr ft2)

2 Openings Adjacent Walls

Strategy’s Implementation Considerations

(Inlet Area / Floor Area) x 100 Heat removed per unit Floor Area (based upon a 1.7oC [3oF] temperature difference) as a function of size of inlet openings and wind speed (Alison G. Kwok, 2007) Image 7. Jalousie Window

Image 8. Shuttered Casement Window

Image 9 . The Nest House’s Open Floor Plan

(http://www.uniquehomeinterior.com/concentration-of-the-window)

(http://www.curtains.interiordezine.com/curtain-photos)

(www.archdaily.com/381335/the-nest-a21studio)

Cross Ventilation Cooling Capacity

Cross Ventilation diagrams adapted from Sun, Wind & Light by G.Z. Brown and Mark DeKay, published by Wiley

53


If appropriately used, STACK VENTILATION can effectively provide cooling for the internal spaces even on breezeless days Stack Ventilation Types

Strategy’s Implementation Considerations In order for stack ventilation strategies to work well in the climates of Vietnam, a large temperature differential between exhaust air and incoming air must be present. This can be done in several ways including increasing stack height. The higher the stack, the greater the temperature differential. It is stated that “a typical stack will provide effective ventilation for areas within the lower half of its total height. This implies that stacks be double the height of the building if they are to serve all flloors of a building, or that they only serve a portion of the total flloor area.” (Allison G. Kwok, 2007) Stacks can be either enclosed within the building or exposed to the outside depending on the desired aesthetics, internal space planning, cooling loads & climate conditions. Temperature conditions of in-take air can be kept low via the use of exterior finishes, plants and ground covers. Size, placement & quantity of stack openings (inlet, outlet and throat area) must be carefully considered as they significantly affect the strategy’s overall effectiveness, building security, appearance and air quality. During the design process, practitioners can determine the target stack cooling capacity using the chart below.

Stack Cooling Capacity (W/m2)

Stack Cooling Capacity (Btu/hr ft2)

Stack Ventilation Cooling Capacity

Natural ventilation Stack Ventilation Applicability

Image 1. Le Mon House

Image 2. Lucky Shop House Extension

(www.archdaily.com/241950/le-mon-writeup-fabian-tan/)

(www.archdaily.com/320233/lucky-shophouse-chang-architects/)

A. Tall Rooms

Stack ventilation provides cooling for building’s occupants in the three climates of Vietnam. This strategy is particularly effective in the context of the three studied cities, especially in the densely populated urban area, due to its independence of wind conditions. However, if strategically implemented with wind fllow & solar energy, its effectiveness can be greatly enhanced.

Overview

Image 3. Lucky Shop House Big Room

Image 4. 36BTrd House Big Entry Space

(www.archdaily.com/320233/lucky-shophouse-chang-architects/)

(www.archdaily.com/199918/36-btrd-dp-architects/)

Image 5. Nha Beo House Light Well

Image 6. Gia Lai House In-House Atrium

(www.archdaily.com/246049/a21house-a21-studio)

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects/)

B. Tall Room at Edge

C. Tall Room Within (Atrium)

Stack ventilation takes advantage of the vertical pressure difference caused by thermal buoyancy effect. Similarly to cross ventilation, this strategy, if used strategically and accordingly to climate conditions, can be an excellent alternative to mechanical cooling in the building. Stack ventilation’s mechanism relies on two basic principles: “(1) as air warms, it becomes less dense and rises; (2) ambient (hopefully cooler) air replaces the air has risen.”(Alison G. Kwok, 2007) It creates its own air current, “where warmer air is evacuated at a high point, and cooler outdoor air is brought in at a lower level” (Alison G. Kwok, 2007). Stack ventilation should be considered in tangent with cross ventilation since same openings may contribute to both of these strategies. The effectiveness of this strategy is a function of the following factors: • The height of the stack • Indoor and outdoor temperature differential • Size of openings

Advantages

Image 7. Stacking Green House Light Well

Image 8. A21 House Light Well

(www.archdaily.com/199755/stacking-green-vo-trong-nghia/)

(www.archdaily.com/246049/a21house-a21-studio)

D. Dedicated Stack

•This strategy lowers the temperatures of the internal spaces •The air movement increases perceived comfort range by 2-4oC •Stack ventilation is a great alternative to mechanical cooling, thus reducing energy consumed for cooling of internal spaces

Challenges & Limitations (Stack Area / Floor Area) x 100 Heat removed per unit Floor Area (based upon a 1.7oC [3oF] temperature difference) relative to stack size and height (Alison G. Kwok, 2007) Image 9. 4.5x20 House Open Staircase

Image 10. M11 House Staircase Stack

(http://www.archdaily.com/336393/4-5x20-house-ahl-architects-associates)

(www.archdaily.com/98450/m11-house-a21-studio/)

Cross Ventilation diagrams adapted from Sun, Wind & Light by G.Z. Brown and Mark DeKay, published by Wiley

54

E. Staircase as Stack

Practitioners must carefully and appropriately determine the height of the stack, the indoor & outdoors temperature differential and the size of openings in order to maximize the cooling potentials of this strategy. Also, noise, pollution and distribution of cool air must be taken into account in order to achieve desirable IEQ.


SOLAR ENERGY CAN BE USED TO INCREASE THE TEMPERATURE DIFFERENTIAL WITHIN THE VERTICAL STACK, THUS ENHANCE VENTILATION Solar Chimney Overview A solar chimney uses the sun’s heat to induce air

Natural ventilation

movement via the stack effect. Solar heat gain warms the interior

Solar-induced Stack

air, which then rises, pulling the outside air inside the building. This induced air movement consequentially cools the internal spaces

Strategy’s Applicability

of the building. This application of solar-induced stack ventilation

The buildings in the three studied cities are exposed to intense sun throughout most the year. With that said, solar energy can be used to induce stack ventilation as it increases the temperature differential between the entering & exiting air.

is especially effective in Vietnam’s urban area with unfavorable wind conditions and lots of sun. Solar Chimney Application Types

Overview

Image 4. DA & A House by DA & A architects Light Well with glass cover for solar-induced stack ventilation (http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html)

Image 5. 36 BTrd House by DP Architects Heat gain from roof solar panels enhances air movement within the staircase stack (www.archdaily.com/199918/36-btrd-dp-architects/)

Image 7. Suoi Re Village Community House by 1+1>2 Group Exposure roof with glass cover for solar-induced stack ventilation (http://www.archdaily.com/102639/suoi-re-village-community-house-kiến-việt)

Image 8. S11 House by ArchiCentre Highly glazed vertical stack equipped with turbine air ventilator for enhanced stack ventilation (http://www.archdaily.com/313041/s11-house-archicentre/)

Image 1. Singapore ZEB (http://energyblog.nationalgeographic.com/2012/07/05)

Black-Painted Solar Chimney

Image 2. No.19 ArchiCentre (Malaysia) (http://www.archdaily.com/347424/no-19-archicentre)

Integrated Trombe Solar Chimney

Air Ventilator at the top of vertical stack

Image 3. Natural Energy Laboratory, HI (http://www.aiatopten.org/node/142)

Integrated Trombe Roof Structure

Image 8. Open Stack Air Ventilator

Image 9. Solar Powered Air Ventilator

Image 10. Turbine Air Ventilator

(http://www.rona.ca/fr/ventilateur-de-toit-6467006--2)

(http://www.icanfixupmyhome.com)

(http://www.colt-tollfab-victoria.com/turbine-roof-ventilators/)

Air ventilator, if used effectively, can draw out warm and humid air accumulating at the top of the vertical stack using both bouyancy effect and wind conditions. This device is able to not only prevent unwanted heat gain from the overhead sun but also to cool the building. There are several types of air ventilator available in the market.

Solar-induced ventilation functions based on the two basic principles: (1) as air warms, it becomes less dense and rises; (2) cooler ambient air replaces the air has risen. Solar-induced ventilation relies solely on the sun to thermally create the temperature stratifications that are the source of wind itself. This induced air movement augments natural ventilation to aid the building’s occupants in reaching thermal comfort. As air warms, it becomes less dense and rises, seeking its way upward and drawing coolest replacement air from shaded or planted outdoor area below. By using the sun to heat an isolated pocket of indoor air to “ a greater than ambient temperatures and controlling its escape, a building can generate air circulation and maximize the influx of cooler air” (AIA Research Corporation, 1979). The most effective application of this strategy is the solar chimney, a sun-exposed tall enclosure that uses solar energy to “create temperature differences, cause continuous air circulation through the house, and provide ventilation cooling relief.” (AIA Research Corporation, 1978)

Advantages The strategy is able to provide air movement independent of outside wind conditions. This is especially important for densely populated urban areas where the overall air porosity greatly diminishes rendering wind-induced ventilation ineffective.

Challenges & Limitations In order to maximize the effectiveness of this strategy, stack pressures must also be carefully evaluated. Also, fresh air inlets must be appropriately sized in order to maintain the consistent circulation of hot & cool air within the stack. Lastly, caution must be taken in order to avoid unwanted solar heat gain from the overhead sun.

Solar Chimney Ventilation Diagrams illustrated by Duy Vo

55


c. Natural Daylighting

Due to its geographical location, Vietnam has

great access to abundant source of natural daylight. Daylight provides more desirable and better quality illumination than artificial light sources. In addition, if strategically used, it can help with the reduction of energy consumption within the building for electric lighting as well as cooling. With that said, it is important that practitioners try to integrate natural day lighting strategies into building design. For cooling dominant climates such as the 3 Vietnamese cities in this study, window openings and shading devices together should be treated as an integrated daylighting system.

56


Internal reflectances can be used to bring natural daylight deeper into the space

INTERNAL REFLECTANCES

Smooth or glossy surfaces create specular reflections whereas matte-finished surfaces create diffused reflected light. As specular reflections can cause visual discomfort, smooth or glossy surfaces should be used with caution. Practitioners should advise

Color & Texture Applicability

clients on the color, texture of materials according to the location of the surfaces and function of the spaces. Recommended Reflectances for Interior Surfaces in Residences Surface

Recommended Reflectances

Ceilings

60 - 90%

Walls

35 - 60%

Floors

15 - 35%

Furnishings

35 - 60%

Image 1. M11 House

Image 2. 4.5 x 20 House

Image 3. Allzone House

(www.archdaily.com/98450/m11-house-a21-studio/)

(www.archdaily.com/336393/4-5x20-house-ahl-architects-associates/)

(http://www.archdaily.com/105334/shophouse-transformation-allzone/)

Overview

Excerpted from Alison G. Kwok, 2007

Reflectances of Common Building & Site Materials Material

Reflectance

Aluminum

85%

Asphalt

5 - 10%

Brick

10 - 30%

Concrete

20 - 30%

Gravel

20%

Plaster, white

40 - 80%

Water

30 - 70%

Vegetation

5 - 25%

In the dense urban context of the three studied cities, internal reflectances would be of great benefit since they further invite natural daylight deep into the building reducing the amount of energy consumed for electric lighting.

Image 4. A21 House

Image 5. Park House

Image 6. Le Mon House

(www.archdaily.com/246049/a21house-a21-studio/)

(www.archdaily.com/212939/the-park-house-formwerkz-architects/)

(www.archdaily.com/241950/le-mon-writeup-fabian-tan/)

Excerpted from Alison G. Kwok, 2007

Reflectances of Typical Paint Colors

The internal reflectances of the interior surfaces plays an important role in allowing natural daylight to enter deep into the building. It not only determines the quantity but also the quality of light provided by internal reflection. The internal reflectances of a space “are governed by two primary surface characteristics of the bounding materials - color and texture” (Alison G. Kwok, 2007) The amount of light reflected from an internal surface is dependent on color whereas the quality of light leaving the surface is a function of texture. A highly reflective interior surface increases the internally reflected proportion of day light factor, which in turn enhances the overall illumination of the spaces. It is important that “the surface that first reflects the light be light in color to increase the amount of light reflected into the space. This surface may be the flloor when light is coming directly from the sky, or the ceiling if the light is being refllected from exterior ground surfaces.”(Brown, 1985). Depending on the location of the surface in relation to the daylight source, the reflectance may vary.

Color

Reflectance

White

80-90%

Pale Blue

80%

Canary Yellow

75%

Lemon Yellow

65%

Dark Cream

60%

Light Blue

55%

Challenges & Limitations

Light Green

50%

Apricot

45%

Apple Green

40%

Medium Brown

35%

Red-orange

30%

Dark Red, Blue, Gray

15%

Red-orange

5%

• Depending on the type of activities taken place inside the internal spaces of the building, practitioners must appropriately select the according light-colored paint. • Over time, the surface brightness of the internal surfaces will be subjected to light loss due to dirt accumulation and wear and tear. Practitioners should employ paint with greater initial illuminance, if possible, to compensate for the maintenance factor of the surfaces.

Excerpted from Alison G. Kwok, 2007

Advantages Image 7. Lucky Shop House Extension

Image 8. 55 Blair Road Residence

Image 9. Go Vap House

(www.archdaily.com/320233/lucky-shophouse-chang-architects/)

(www.archdaily.com/32573/55-blair-road-ong-ong/)

(www.archdaily.com/240562/house-in-go-vap-mm-architects/)

Image 10. Gia Lai House

Image 11. 31 Blair Road Residence

Image 12. Cairnhill Road Terrace House

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects/)

(http://www.archdaily.com/29550/31-blair-road-residence-ong-ong/)

(http://www.archdaily.com/360556/128g-cairnhill-road-richardho-architects/)

This strategy allows natural daylight to enter further into the building, thus reducing energy consumed for electric lighting.

57


d. Evaporative Cooling

58


WHEN IT IS HOT & DRY, evaporative cooling can provide coolth & MOISTURE to the internal spaces of the building HA NOI

Evaporative Cooling via Inner Court Pool Inner court pool can be used to evaporatively provide coolth for building’s occupants. As warm air passes over the body of water, it causes evaporation, which in turn cool and humidify the immediate surroundings. In order for cooled and dehumidified air to be distributed into the building, the pool should be placed between walls and in the path of cross breezes.

Very high humidity levels with little diurnal fluctuation

DA NANG

HO CHI MINH CITY

High humidity levels with significant diurnal fluctuation during a short time period between June & August. 25

High humidity levels with most significant diurnal humidity fluctuation from December to May 25

30

30

Evaporative cooling is not feasible in Ha Noi

EVAPORATIVE COOLING

20

20

15

15

10

10

Plant’s Evapotranspiration Overview

Evaporative Cooling via Plant’s Evapotranspiration Another natural means to evaporatively cool the building’s internal spaces is through plant’s evapotranspiration. As plant’s leaves lose moisture through their pores, the surrounding air around the leaf is cooled. Similarly to the inner pool, vegetation should be strategically planted in the path of DBT(°C) 5 10 cross breezes so that cooled and humidified air can be distributed throughout the building.

Comfort

Comfort

Comfort 5

5

15

20

DBT(°C) 25

530

1035

Practitioners should not use evaporative cooling strategies in the climate of Ha Noi due to the high humidity levels year round.

15 40

2045

2550 DBT(°C)

5 30

1035

Though evaporative cooling strategies may be of benefit in the short & somewhat “dry” period, they are more likely to not be feasible for the rest of the year due to consistently high levels of humidity.

15 40

2045

25 50

30

35

Evaporative cooling strategies are effective during the “dry” period from December to May. However they must be carefully implemented in order to prevent it from becoming ineffective during the other humid half of the year.

Evaporative Cooling via Inner Court Pond

Evaporative cooling is an energy efficient alternative to mechanical cooling that provides effective natural cooling in somewhat dry climates. Its mechanism relies on the evaporation process of water into water vapor, which results from the conversion of the air’s sensible heat into latent heat due to the presence of either moisture or bodies of water in an overheated climate in order to convert the air’s sensible heat into latent heat. With the humidity of the air increases, the dry bulb temperature drops, thus making the environment more comfortable. An evaporative cooling system requires “simply the addition of bodies of water or of moisture for cooling the living spaces.” (AIA Research Corporation, 1978). Fountain courts or atrium pools are amongst some of the applications of this strategy that effectively provide a much cooler and more humid environment for homes in dry and somewhat dry climates. In addition, evaporative cooling can “also be put to work to cool radiative roof deck or any other radiative surface in contact with interior spaces. If a roof is sprayed with water, evaporation cools the roof surface, encouraging its absorption of heat from the interior and the dispersal of that heat into the atmosphere.” (AIA Research Corporation, 1979)

Advantages This strategy greatly benefits areas located in hot & dry climates as it cools and adds extra moisture to the dry air that circulates within the building. Image 1. Nhabeo House

Image 2. A21 House

(www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/)

(www.archdaily.com/246049/a21house-a21-studio/)

Challenges & Limitations •Evaporative cooling is only feasible and most effective in dry & somewhat dry climates. •Water must be available in quantity for evaporative cooling to continue. •Evaporative cooling systems must be protected from the sun as it is the air’s heat, not solar heat, that is needed for the evaporation process •Wind-induced ventilation such as cross ventilation & stack ventilation should be coupled with evaporative cooling so that cool, humidified air can be most efficiently distributed.

Image 3. Gia Lai House

Image 4. The Nest House

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects/)

(www.archdaily.com/381335/the-nest-a21studio/)

Image 1. 55 Blair House

Image 2. Lorong 24A Shophouse Series, No.19

Image 3. Lorong 24A Shophouse Series, No. 13

(www.archdaily.com/32573/55-blair-road-ong-ong/)

(http://www.thelor24ashophouseseries.com/19designstatement.htm)

(http://www.thelor24ashophouseseries.com/13designstatement.htm)

59


d. Time Lag Cooling

60


THERMAL MASS & night purge CAN take advantage of significant diurnal swing PROVIDING COOLTH TO THE BUILDING'S OCCUPANTS HA NOI

Time Lag Through Homogenous Walls Materials

Thickness (in.)

U-factor (Btu/h ft2)

Time Lag (h)

8

0.67

5.5

Granite

12

0.55

8.0

16

0.47

10.5

24

0.36

15.5

2

0.98

1.1

4

0.84

2.5

6

0.74

3.8

8

0.66

5.1

12

0.54

Solid Concrete

Common Brick

DA NANG 25

25

20

20

15

15

10

10

Comfort

Comfort

TIME LAG COOLING

HO CHI MINH CITY

Thermal Mass & Night Purge Overview

Comfort 5

5

7.8 DBT(°C)

5

16

0.46

10.2

12

0.54

7.8

16

0.46

10.2

16

0.46

10.2

16

0.46

10.2

10

Excerpted from (Alison G. Kwok, 2007)

15

20

DBT(°C) 25

No Significant Diurnal Swing Detected During The Year

530

1035

Thermal Mass and Night Purge are not feasible

15 40

2045

2550 DBT(°C)

5 30

1035

Significantly Large Diurnal Swing from May to August

Practitioners should avoid using Practitoners should be mindful materials with high thermal mass as they when using thermal mass & night purge absorb solar heat & increase the cooling in the climate of Da Nang as the diurnal demands in the building. swing is only present for half of the year.

15 40

2045

25 50

30

Significantly Large Diurnal Swing Through Out The Year

Thermal mass & night purge are especially effective in Ho Chi Minh City due to the significant diurnal swing throughout the year.

Nocturnal Ventilative Cooling Nocturnal ventilative cooling employs circulation of cool outdoor air only at night to relieve the internal heat gain accumulated during the day from the internal masses of the building. It compliments night purge cooling while enhancing the overall effectiveness of thermal mass. However, as this strategy requires opening up the building during the night time for air flow to breeze through, it poses major concerns for both practitioners and clients, especially in the context of Vietnam: security, rain water and insects. Practitioners should address these issues accordingly.

Application: Roof Pond Roof pond is another application of thermal mass and night purge cooling. It involves the use of a contained body of water on the roof that is protected, when needed, by movable insulated panels. During the day when it is too hot for comfort, the panels cover the pond in order to: (1) protect the contained water from the sun and (2) help the contained water to remain chilled allowing for the absorption of heat from the interior spaces to take place. During the night, the panels open up, exposing the now warm water to the clear night sky allowing for the release of the heat to the sky dome. When using this application, practitioners must ensure quality construction to avoid water leakage.

35

Image 1. Sentosa House

Image 2. Alleyway House

Image 3. Le Mon House

(http://www.archdaily.com/301786/sentosa-house-nicholas-burns/)

(http://www.archdaily.com/69545/alleyway-house-formwerkz-architects)

(www.archdaily.com/241950/le-mon-writeup-fabian-tan/)

Thermal mass capitalizes on the process of thermal absorption by high mass materials such as stone, concrete, masonry, etc… and the large diurnal swing. Its mechanism relies on the basic principle that the heat transmission through these materials is delayed and significantly reduced over a period of time. The type of materials as well as the thickness of the mass wall both determines the duration in which the delay stretches. The greater the stretch, “the greater the attenuation of heat transmitted” (AIA Research Corporation,1979). As a result, “less heat reaches the interior spaces, and it does not arrive until late evening or night, when ambient temperatures have dropped and the exterior wall is radiatively cooling. By night’s end the wall is again a cold barrier to the daytime onslaught of insolation.” (AIA Research Corporation,1979). Exterior sheathing, insulation, vegetation should also be considered as they help further flattening the large diurnal swing. Night purge cooling is “an indirect heat-loss process that involves exposing interior spaces to the heat sink of a massive body of water or masonry, then exposing the mass to the planetary heat sink of a cool, clear night sky.” (AIA Research Corporation, 1979) The well-sized & exposed body of water or masonry, acting as a cold storage, absorbs the heat accumulated by the interior spaces during the day and then release that heat to night sky. This process, consequently, provides natural cooling for the building’s occupants. Night purge cooling is most effective when there is a relatively clear night sky in addition to a large enough diurnal swing, as “radiative losses to the vast heat sink of deep space are impeded by the greenhouse effect of cloud cover.” (AIA Research Corporation, 1979).

Advantages This strategy reduces both peak air temperatures and temperatures during the morning hours. It, in turn, reduces the amount of energy consumed for mechanical cooling.

Challenges & Limitations For this strategy to work, thermal mass needs to be exposed to a clear cool night sky. In addition, a significant diurnal swing is required. Image 4. S11 House

Image 5. Gia Lai House

Image 6. DA & A House

(www.archdaily.com/313041/s11-house-archicentre/)

(www.archdaily.com/239502/gia-lai-house-vo-trong-nghia-architects/)

(http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html)

61


5. Regional Case Studies 1. Stacking Green House (Ho Chi Minh City, Vietnam) 2. A21 House (Ho Chi Minh City, Vietnam) 3. 4.5 x 20 House (Ha Noi, Vietnam) 4. M11 House (Ho Chi Minh City, Vietnam) 5. Le Mon House (Kuala Lumpur, Malaysia) 6. 36 BTrd House (Singapore City, Singapore) 7. 3 x 9 House (Ho Chi Minh City, Vietnam) 8. Lucky Shop House (Singapore City, Singapore) 9. Nhabeo House (Ho Chi Minh City, Vietnam) 10. The Nest House (Binh Duong, Vietnam) 11. DA&A House (Ha Noi, Vietnam) 12. The Pool Shop House (Singapore City, Singapore)

62


CASE STUDY

01

63


CS 01

Stacking green house Ho Chi Minh City Vietnam Tropical Hot & Dry Residential 80 m2 4 4 Vo Trong Nghia Architects

Building Floor Plans

(1) Vegetated terrace keeps the roof cool & captures rainwater.

(2) Deep light well allows for enhanced stack ventilation and brings natural daylight inside.

(3) Interior spaces are naturally lit and well-shaded against solar heat radiation during the day.

(4) Vegetated facade consists of light-colored & planted horizontal shading elements.

Building sectional diagram illustrated by Duy Vo - Photographic images and fl oor plans retrieved via http://www.dezeen.com/2012/07/09/stacking-green-by-vo-trong-nghia/

64


HA NOI

DA NANG

Due to the lack of significant diurnal swing, time-lag cooling via the use of thermal mass in building is neither applicable nor even feasible in the climate of Ha Noi.

Da Nang experiences a considerable diurnal swing for half of the year, thus the use of thermal mass in this climate may be of benefit. However, caution must be taken for the period where the diurnal swing is minimal.

Not Applicable

Apply with caution

HO CHI MINH CITY

Stacking green house Ho Chi Minh City experiences significantly large diurnal swing during most months the year, therefore the use of thermal mass in this climate is highly beneficial.

Applicable

Ho Chi Minh City Vietnam Building Overview This tube house, designed for a thirty-year-old couple and their mother, is constructed on a 4-meter-by-20-meter lot of land. The front and back facades of this residence are slatted by a series of horizontal concrete planters. The building’s principal architect, Vo Trong Nghia, named it “Stacking Green” because “its facades filled with vigorous and vital energy”

THERMAL MASS: CONCRETE & GREY STONE On hot and windless day in Ha Noi, especially in the urban area, solar-induced stack ventilation enhances air movement, thus further cooling the interior spaces. However, caution must be taken in order to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, building’s occupants in Da Nang should benefit from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

Building’s occupants in Ho Chi Minh City can benefit from this strategy. With low sky coverage throughout the year, this strategy should be easily employed. However, unwanted solar heat gain must be prevented at all cost.

Apply with caution

SOLAR INDUCED STACK VENTILATION Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT VIA LIGHT WELLS Photographic images and building site plan retrieved via http://www.dezeen.com/2012/07/09/stacking-green-by-vo-trong-nghia/

65


HA NOI

DA NANG

Buildings in Ha Noi can benefit from having green roofs since they prevent the temperature conditions directly below the roof from rising due to solar heat gain during the hot months.

Similarly to Ha Noi, buildings in Da Nang would also benefit from having vegetated roof since most of the year the temperatures remain consistently high.

Applicable

Applicable

HO CHI MINH CITY

Stacking green house Out of the 3 cities, a green roof would most benefit Ho Chi Minh City since the outdoor temperatures throughout the year remain consistently within the 21oC 38oC range.

Applicable

VEGETATED ROOF TOP Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants.

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS Reflective colored external surfaces reduce cooling demand in Ha Noi by preventing the interior temperature conditions from rising due to direct solar heat gain.

Applicable

Reflective colored external surfaces reduce cooling demand in Da Nang by preventing the interior temperature conditions from rising due to direct solar heat gain.

Applicable

REFLECTIVE COLORED EXTERNAL SURFACES Photographic images retrieved via http://www.dezeen.com/2012/07/09/stacking-green-by-vo-trong-nghia/

66

With consistently intense sun in Ho Chi Minh City, white colored external surfaces, as used in this building, are an effective means to prevent internal temperature increase.

Applicable

Ho Chi Minh City Vietnam


HA NOI

DA NANG

HO CHI MINH CITY

A vegetated building facade helps modulating the temperatures on the inside, sequester carbon dioxide and reduce the urban heat island effect. Buildings in Ha Noi can definitely benefit from this strategy.

Similarly to Ha Noi, buildings in Da Nang would also benefit from having a vegetated building facade since the temperature conditions in this city remain mostly high throughout the year.

Out of the 3 cities, a vegetated facade would most benefit Ho Chi Minh City since the outdoor temperatures throughout the year remain consistently within the 21oC - 38oC range.

Applicable

Applicable

Stacking green house Ho Chi Minh City Vietnam

Applicable

VEGETATED BUILDING FACADE During the hot period in Ha Noi, having large openings in direction of the prevailing winds would be effective. However, they must be carefully shaded to avoid unwanted solar heat gain. Also, caution must be taken during the cold period.

Apply with caution

Similarly to Ha Noi, this strategy can definitely be beneficial to the building’s occupants in Da Nang, especially during the hot period. Shading and reduction of infiltration must be implemented to avoid causing thermal discomfort.

Apply with caution

Out of the 3 cities, building’s occupants in Ho Chi Minh City would benefit most from this strategy. However, shading of these large openings must be carefully executed to avoid unwanted solar heat gain.

Apply with caution

LARGE OPENINGS FOR air flow Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the bathroom is located next to the vertical void, allowing moisture to be driven out by the induced updraft

Applicable

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building.

Applicable

Building’s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

HUMIDITY RELIEF VIA bathroom ZONING Photographic images retrieved via http://www.dezeen.com/2012/07/09/stacking-green-by-vo-trong-nghia/

67


HA NOI This tube house uses protruding horizontal planters as shading devices for both the front and back facades. Planters are spaced 25mm to 40 mm away from each other depending on the type of plants planted. The according shading mask is illustrated for the 40mm-spaced planter. Speculation on details was made based on photographic images of the device.

N

345°

DA NANG 15° 30°

45°

300°

nt rma Do

1st May 285°

60°

1st Jul

60° 1st Jul

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

30°

315°

45°

300°

1st Jul

15°

330°

30°

315°

Period

N

345°

15°

330°

315°

1st Jun

N

345°

330°

HO CHI MINH CITY

285° 1st May

75°

75° 1st Aug

1st Sep 1st Sep

Permanent device

1st Apr

1st Oct

1st Jan 315°

15

16

17

240°

Permanent device

Period nt rma Do

14

13

165°

180°

Building Block (HA NOI) 1st Apr

1st Sep

270°

90° 1st Oct N 345° 1st Mar 1st Nov 255° 105° 1st Feb

12

11

315° 10

9

8

1st Jan 1st Dec 240° 120°

7

15°

1st Jun

195°

1st Nov 105°

17

14

15

45°

13

12

11

10

9

8

7

1st Dec 120°

225°

135°

1st Mar

1st Jan

17

14

13

210°

150°

150°

75° 195°

225°

12

240°

11

10

Period

13

9

8

225°

195°

7

1st Nov 255° 1st Feb105°

8

1st Jan Dec 1st

7

15

13

14

12

11

1st Nov 105° 9

8

45°

1st Dec

7

240°

120°

135°

270°

255° 1st Feb 17

1st Jan

16

210°

120°

195°

60° 1st Jul

14

13

150°

Building Block 1st Apr

270°

165°

1st Sep 90°

(Ho1stChiMarMinh N city) 1st Oct 345° 255° 105° 1st Feb 1st Nov 1st Jan

330° 12

11

10

9

8

7

315°

15°

225°

1st Sep

16

15

105°

17

16

15

14

13

12

11

10

210°

8

240°

225°

165°

180°

16

14

13

12

11

135°

150° 165°

1st Oct

10

9

8

1st Nov

7

1st Dec 120°

225°

135°

210°

150° 195°

17

15

240°

135°

210°

1st Nov

7

105°

1st Jan

120°

8

1st Sep

255° 1st Feb

1st Dec

7

9

1st Dec 120°

75° 1st Aug

195°

1st Mar

9

10

1st Jul

165°

1st Oct 1st Nov 105°

11

13

14

225°

150°

195°

90°

45°

135°

285° 1st May

210°

1st Sep

1st Oct

60°

1st Jun

165°

75° 1st Aug

30° 17

1st Dec 240° 120°

240°

150°

75° 195°

45°

135°

1st Apr

1st Jan

1st Dec

15

1st Aug 150°

30°

1st Dec 120°

300°

1st Jul

165°

7

300°

285° 1st May 75° 1st Aug 180°

210°

60° 225°

135°

60°

285° 1st May

1st Mar

10

8

1st Nov

1st Jun Jul

1st Apr

30° 16

17

255° 1st Feb

150° 180°

15°

9

15°

105°

330°

10

45°

225°

1st Sep

90° 1st Oct

11

315°

1st Jun

1st Apr

135°

210° 195°

9

1st Mar

nt rma Do

14

10 315°

1st May 285°

210°

165°

Permanent device 15

16

11

1st Jun

1st Nov 105°

17

75°

165°

270° 90° 1st Oct 1st Mar N

330° 12

1st Oct

255° 1st Feb

Building Block (DA NANG) 120°

1st Sep

1st Mar

150°

180° 1st Sep

240°

1st Aug

165°

1st Jan

15

300°

1st Aug

12

13

14

240°

1st Jul

1st Apr

255° 1st Feb 16

60° 135°

75°

345°

315°

30° 15 16

17

1st Jan 45°

120°

1st May 1st Aug 285° 195°

1st Dec

7

1st Jun 1st Jul 210°

270°

8

1st Oct

345°

15° 255° 1st Feb

330°

300°

60°

1st May 285°

1st Apr

9

300° 135°

1st Jul

1st Apr

45°

225°

60°

1st May 285°

210°

90° 1st Oct

10 315°

1st Jun

1st Sep

30°

16

300° 225°

75°

11

345° 30°

Permanent device

195°

1st Aug

12

13

14

240°

300°

1st Jul

15

16

15°

Permanent device

15

16

150°

75°

330°

315°

60°

Period

17

240°

135°

17

1st Nov 105°

330°

30°

1st Jan

45°

345°

15° 255° 1st Feb

330°

1st Dec

7

Permanent device

1st Jan

8

1st May 1st Aug 285°

210°

255° 1st Feb

9

300° 60° 1st Jun 1st Jul

1st May 285°

1st Mar

10 315°

345° 30°

120°

225°

270°

11

45°

1st Jun

1st Apr

12

13

14

1st Mar

1st Mar

15°

nt rma Do

300°

1st Nov 105°

330°

30°

Permanent device

345°

15°

255° 1st Feb

Permanent device

1st Mar

1st Sep

1st Oct

Permanent device

345° 330°

Permanent device

1st Apr

Permanent device

Permanent device

1st Apr

150° 195°

165°

180°

165°

VSA angle = 63.4o

Dormancy during cold months

Shading from planted vegetation

Permanent device

NORTH SOUTH

Applicable Applicable

EAST WEST

Not Applicable Not Applicable

North: The permanent horizontal shading elements & the plants should adequately shade the building together. South: The permanent horizontal shading elements & the plants should adequately shade the building together. East: During the cold months, the plants will become dormant, thus not effective for shading. That coupled with the short horizontal elements renders this system ineffective. West: Similarly to the East facade, this system will be ineffective especially during plant’s dormant period.

NORTH SOUTH

Applicable Applicable

EAST WEST

Apply with caution Apply with caution

North: The permanent horizontal shading elements & the plants should adequately shade the building together. South: The permanent horizontal shading elements & the plants should adequately shade the building together. East: Unlike Ha Noi, Da Nang experiences a shorter & less severe cold period, thus the plants should remain active throughout the year rendering this system effective. West: The system is effective here. Caution must be taken. Caution: Native plants should be used to avoid excessive watering and death due to water dehydration.

NORTH SOUTH

Apply with caution

EAST WEST

Apply with caution Apply with caution

North: The permanent horizontal shading elements & the plants should adequately shade the building together. South: The permanent horizontal shading elements & the plants should adequately shade the building together East: The system is adequate here since the plants remain active all year long. Caution must be taken. West: The system is adequate here since the plants remain active all year long. Caution must be taken. Caution: Native plants should be used to avoid excessive watering and death due to water dehydration.

HORIZONTAL VEGETATED SHADING DEVICE Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.dezeen.com/2012/07/09/stacking-green-by-vo-trong-nghia/

68

Applicable


CASE STUDY

02

69


CS 02

A21 house Ho Chi Minh City Vietnam Humid Subtropical Live Work 40 m2 4 3+ A21 Studio

Building Sectional Views

(1) Permeable interior spaces enhance the effectiveness of cross ventilation in the building.

(2) Occupantâ&#x20AC;&#x2122;s rooms are shaded with bamboo roller shades to avoid overheating.

(3) Open structure with open roof enhances stack ventilation & invite daylight inside.

(4) Refl ective interior surfaces allow the internal spaces to be naturally lit.

Building sectional diagram illustrated by Duy Vo - Photographic images and axonometric drawings retrieved via http://www.archdaily.com/246049/a21house-a21-studio/

70


HA NOI Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

DA NANG

HO CHI MINH CITY

A21 house This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

Ho Chi Minh City Vietnam Building Overview This tube house, situated in an oddly shaped 40-square-meter lot, consists of 3 storeys and a roof terrace. This building was designed to house both the office space and living space for the a21 studio’s principal architect and his family. He compares the A21 house to “a wild-cage which is bathed in sunlight, inundated by rain-water, fully surrounded by tree… and non-frontier space”

REFLECTIVE INTERNAL SURFACES The introduction of courtyards in the building allows for stack ventilation to take place. This strategy is of benefit in Ha Noi. However, caution must be taken to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, building’s occupants in Da Nang should benefit greatly from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

Building’s occupants in Ho Chi Minh City can benefit from the enhanced internal air movement due to stack ventilation via the courtyard. However, unwanted solar heat gain from above must be prevented at all cost.

Apply with caution

STACK VENTILATION via vertical voids Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants.

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS Photographic images are retrieved via http://www.archdaily.com/246049/a21house-a21-studio/

71


HA NOI

DA NANG

The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Similarly to Ha Noi, buildingâ&#x20AC;&#x2122;s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

Apply with caution

HO CHI MINH CITY

A21 house Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Applicable

PERMEABLE SURFACES FOR BETTER AIR FLOW Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT FROM OVERHEAD SUN Due to the lack of significant diurnal swing, time-lag cooling via the use of thermal mass in building is neither applicable nor even feasible in the climate of Ha Noi.

Not Applicable

Da Nang experiences a considerable diurnal swing for half of the year, thus the use of thermal mass in this climate may be of benefit. However, caution must be taken for the period where the diurnal swing is minimal.

Apply with caution

THERMAL MASS: BRICK & CONCRETE Photographic images retrieved via http://www.archdaily.com/246049/a21house-a21-studio/

72

Ho Chi Minh City experiences significantly large diurnal swing during most months the year, therefore the use of thermal mass in this climate is highly beneficial.

Applicable

Ho Chi Minh City Vietnam Aerial View of A21 House


HA NOI The shading device of the building consists of a series of evenly-spaced and angled vertical slats. The device, though categorized similarly to vertical fins, has angled slats; thus its overall shading mask is illustrated with 2 different cut-off angles. Speculations on the depth of slats and in-between slats gap were made based on photographic images of the device.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jun

45°

1st Jul

1st Sep

1st Apr

75° 1st Aug

1st Apr

1st Apr

1st Oct 345°

1st Mar

15°

345°

255° 1st Feb

330°

30°

1st Jan

15

16

17

1st Nov 105°

330° 14

45°

12

13

11

10 315°

9

8

300°

60° 225°

1st Jun

210° 195°

270° 1st Mar

345°

255° 1st Feb 15

14

12

13

11

10 315°

9

8

240°

90° 1st Oct

90° 1st Oct 1st Nov 105°

30° 15

14

45°

12

13

11

10

9

8

7

210°

1st Dec 120°

135°

225°

195°

135°

150°

75°

165°

195°

1st Dec

7

1st Apr

1st Sep 180°

1st Jul 1st Aug

150°

Building Block (DA NANG)

75°

165°

270°

345°

255° 1st Feb 1st Jan

1st MarN

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

330° 16

17

15

14

13

12

11

10

9

8

7

315°

90° 1st Oct

240°

1st Nov 105°

30° 17

15

16

13

14

12

10

9

8

45°

1st Dec

7

120°

135°

195°

285° 1st May

210° 195°

210°

150°

165°

195°

1st Sep

345°

255° 1st Feb 1st Jan

17

16

1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

1st Jan

1st Dec

Applicable Not Applicable

180°

17

16

15

13

12

11

10

9

8

225°

North: This device is an effective shading strategy for the building during all the hours where the building is exposed to direct solar gain. South: This device is ineffective since it only shades the building approximately half of the year. East: Similarly to the South orientation, this device is ineffective, therefore should not be used. West: This device is most ineffective in this orientation since it only shades the building for a very small amount of hours during the year

12

13

11

150°

75° 1st Aug

165°

9

8

1st Sep 90°

90°

1st Mar N1st Oct

1st Oct

15°

255° 105° 1st 1st FebNov

330° 10

7

105°

30°

1st Jan 1st Dec 120° 240°

15

16

17

14

11

13

10

9

8

1st Nov

7

1st Dec 120°

45°

60°

285° 1st May

225°

135°

1st Jul 210°

150°

195°

165°

195°

165°

75° 1st Aug

1st Apr

1st Sep

1st Mar

1st Oct

NORTH SOUTH

255° 1st Feb

1st Dec

7

150° 165°

Applicable Not Applicable

180°

105°

1st Jan

17

16

15

13

12

11

10

9

8

225°

135°

210°

150° 195°

Not Applicable Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device is ineffective since it only shades the building approximately half of the year. East: This device is ineffective since it does not shade most of the hours where the building is exposed to the most intense sun. West: This device is most ineffective in this orientation since it only shades the building for a very small amount of hours during the year

1st Nov

7

1st Dec 120°

165°

EAST WEST

14

240°

150° 195°

Not Applicable

14

210°

135°

210°

Not Applicable

60°

135°

Building Block (Ho Chi Minh city)

135°

120°

165°

EAST WEST

14

240°

150° 195°

15

225°

1st Nov 105°

255° 1st Feb

135°

210°

45°

1st Oct

120°

225°

1st Dec 120°

1st Jul

285° 75° 1st May 1st Aug 180°

240°

1st Mar 1st Nov 105°

255° 1st Feb

7

300°

270°

270°

1st Apr

1st Oct

30°

1st Nov

1st Jun

75°

15°

105° 8

300° 135°

1st Jul

150°

9

1st Apr 1st Sep

1st Aug

1st May 285°

210°

225°

10

1st Jul 1st Jun

315°

60°

1st Jun

165°

1st Mar

NORTH SOUTH

11

120° 240°

225°

60°

225°

1st Mar

15°

11

330°

315°

1st Jun

1st Apr

90° 1st Oct

270°

12

45°

1st Sep

1st Apr

13

14

240°

300°

60°

30° 15 16

17

1st Jan 315°

45°

135°

1st 1st Jul Jun 1st Aug 1st May 285° 75°

210°

1st Sep

1st Apr

8

1st Oct

345°

15°

255° 1st Feb

330°

30°

60° 300°

1st Aug 210°

9

300°

1st Jul

150°

10 315°

225°

1st Jun

1st Mar

15°

16

11

345°

15°

1st Mar

120°

195° 1st Sep

17

12

13

14 45°

1st May 285°

60°

1st Jun

15

16

165°

120° 240°

1st May 285°

17

1st Jan

1st Nov 105°

330°

300°

1st Jul 75°

300° 225°

345° 30°

240°

150°

1st 1stDec Jan

7

15°

255° 1st Feb

315°

1st Aug

1st Mar N 1st Nov 255° 105° 1st Feb

330°

16

45°

60°

180° 1st Sep

270°

1st Mar

330°

135°

Building Block (HA NOI) 1st Apr

17

345° 30°

300°

1stJul Jun 1st 1st Aug 1st May 285° 75°

1st Apr

1st Jan

15°

120°

1st May 285°

1st Sep

1st Oct

1st Dec

7

240°

HSA Angle = 22o

1st Jul

285° 1st May

75° 1st Sep

315°

HSA Angle = 63o

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

30°

315°

300°

1st Jul

15°

330°

30°

315°

1st May 285°

N

345°

15°

330°

NORTH SOUTH

Applicable Not Applicable

180°

165°

EAST WEST

Not Applicable Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device is ineffective since it only shades the building approximately half of the year. East: This device is ineffective since it only shades approximately half of the hours where the building is exposed to the most intense sun West: This device is most ineffective in this orientation since it only shades the building for a very small amount of hours during the year

SLANTED VERTICAL SLATS Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.archdaily.com/246049/a21house-a21-studio/

73


CASE STUDY

74

03


CS 03

4.5 x 20 house Ha Noi Vietnam Humid Subtropical Residential 90 m2 4 4 AHL Architects

(1) Interior entrance leads to the triple height circulation core of the building.

(2) Multiple skylights are used to introduce natural daylight deep into the building.

(3) Tall & permeable circulation core allows for cross and stack ventilation to occur.

(4) Interior spaces are naturally lit and well-shaded with internal blinds.

Building sectional diagram illustrated by Duy Vo - Photographic images, fl oor plans retrieved via http://www.dezeen.com/2013/05/14/4-5x20-house-by-ahl-architects-associates/

75


HA NOI

DA NANG

HO CHI MINH CITY

4.5 x 20 house Refl ective internal surfaces, as implemented in this building, are an effective means to invite daylight deep inside the building in the climate of Ha Noi.

Applicable

Similarly to Ha Noi, buildings in Da Nang can significantly reduce electric lighting load via refl ected natural daylight due to the refl ective internal surfaces.

Applicable

With an abundance of daylight in Ho Chi Minh City, buildings here can definitely reduce electric lighting load with the use of refl ective colors on internal surfaces.

Applicable

REFLECTIVE INTERNAL SURFACES On hot and windless day in Ha Noi, especially in the urban area, solar-induced stack ventilation enhances air movement, thus further cooling the interior spaces. However, caution must be taken in order to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, buildingâ&#x20AC;&#x2122;s occupants in Da Nang should benefit from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

Buildingâ&#x20AC;&#x2122;s occupants in Ho Chi Minh City can benefit from this strategy. With low sky coverage throughout the year, this strategy should be easily employed. However, unwanted solar heat gain must be prevented at all cost.

Apply with caution

STACK VENTILATION VIA vertical voids Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT FROM LIGHT WELLS Photographic images retrieved via http://www.dezeen.com/2013/05/14/4-5x20-house-by-ahl-architects-associates/

76

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Ha Noi Vietnam Building Overview This tube house located on narrow lot in Ha Noi, Vietnam, was designed for a young family with children. The architecture of this residence is derived specifically from the space use requirements of the owners. 4.5x20 House features permeable surfaces for enhanced ventilation, a quadruple height atrium that vertically connects all 4 fl oors while bringing daylight inside via the overhead sun.


HA NOI

DA NANG

HO CHI MINH CITY

During the hot months, building’s occupants in Ha Noi can benefit greatly from cross ventilation induced along a corridor. However caution must be taken during the cold months.

Similarly to Ha Noi, building’s occupants in Da Nang would also benefit from this strategy during the hot months. Caution also must be taken during the short cold period.

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the outdoor temperatures throughout the year remain consistently high.

Apply with caution

Apply with caution

4.5 x 20 house Ha Noi Vietnam Building Site Plan

Applicable

CROSS VENTILATION ALONG CORRIDOR Natural daylight is brought inside using the overhead sun. However, shading strategy must be employed to prevent unwanted heat gain. In this case, horizontal slats are used to shade. Ha Noi would benefit from this strategy.

Applicable

This strategy can benefit the buildings in Da Nang as it helps aleviate unwanted heat gain from the overhead sun.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

OPERABLE OVERHEAD SHADE

Photographic images and building site plan retrieved via http://www.dezeen.com/2013/05/14/4-5x20-house-by-ahl-architects-associates/

77


CASE STUDY

78

04


CS 04

M11 house Ho Chi Minh City Vietnam Tropical Hot & Dry Residential 117 m2 3 Not Available A21 Studio

(1) Double height living space is naturally lit while enhancing the stack effect

(2) Refl ective interior surfaces allowing for the rooms to be naturally lit.

(3) Massive concrete wall absorbs overhead solar heat during the day.

(4) The outdoor includes small trees & a pond, allowing for evaporative cooling to occur.

Building sectional diagram illustrated by Duy Vo - Photographic images and fl oor plans retrieved via http://www.designhunter.net/vietnamese-cool-m11-house/

79


HA NOI Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

DA NANG

HO CHI MINH CITY

M11 house This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

REFLECTIVE INTERNAL SURFACES On hot and windless day in Ha Noi, especially in the urban area, solar-induced stack ventilation enhances air movement, thus further cooling the interior spaces. However, caution must be taken in order to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, building’s occupants in Da Nang should benefit from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

Building’s occupants in Ho Chi Minh City can benefit from this strategy. With low sky coverage throughout the year, this strategy should be easily employed. However, unwanted solar heat gain must be prevented at all cost.

Apply with caution

solar-induced stack ventilation Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants..

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

evaporative cooling via plants Photographic images retrieved via http://www.designhunter.net/vietnamese-cool-m11-house/

80

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

Ho Chi Minh City - Vietnam Building Overview The architecture of this 3-storey contemporary house is driven by the needs to accommodate a resting oasis for the clients from the bustling city. As a result, M11 House features various small courtyards while utilizing toplights throughout the interior in order to create nature-infused spaces. The exterior of this house is surrounded by a tall concrete wall that separates the building from its surrounding.


HA NOI

DA NANG

HO CHI MINH CITY

Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Apply with caution

M11 house Ho Chi Minh City Vietnam

Apply with caution

NATURAL DAYLIGHT VIA OVERHEAD SUN Due to the lack of significant diurnal swing, time-lag cooling via the use of thermal mass in building is neither applicable nor even feasible in the climate of Ha Noi.

Not Applicable

Da Nang experiences a considerable diurnal swing for half of the year, thus the use of thermal mass in this climate may be of benefit. However, caution must be taken for the period where the diurnal swing is minimal.

Apply with caution

Ho Chi Minh City experiences significantly large diurnal swing during most months the year, therefore the use of thermal mass in this climate is highly beneficial.

Applicable

TIME LAG COOLING VIA THERMAL MASS Due to the lack of significant diurnal swing, night sky cooling via roof pond in building is neither applicable nor even feasible in the climate of Ha Noi.

Not Applicable

Da Nang experiences a considerable diurnal swing for half of the year, thus this strategy would be effective in this climate. However, caution must be taken for the period where the diurnal swing is minimal.

Apply with caution

Ho Chi Minh City experiences significantly large diurnal swing during most months the year, therefore the use of night cooling in this climate is highly beneficial.

Applicable

NIGHT SKY COOLING VIA ROOF POND Photographic images retrieved via http://www.designhunter.net/vietnamese-cool-m11-house/

81


HA NOI The shading device of this building consists of a series of evenly-spaced horizontal slats. Due to its horizontal orientation, the device is categorized as an overhang, thus its shading mask is illustrated accordingly and similarly to that of an overhang. Speculations on depth of slats and in-between slat gap were made based on photographic images of the building.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jun

45°

1st Jul

1st Sep

1st Apr

345°

1st Mar

15°

345°

255° 1st Feb

330°

30°

1st Jan

1st Nov 105°

330°

15

16

17

14

45°

12

13

11

10 315°

9

8

300°

60° 225°

1st Jun

210° 195°

270° 1st Mar

345°

255° 1st Feb

1st Mar

15

12

13

14

11 315°10

9

8

240°

90° 1st Oct 1st Nov 105°

30°

15

16

12

14 45° 13

11

10

9

8

7

210°

1st Dec 120°

135°

225°

195°

135°

150°

75°

165°

195°

8

1st Dec

7

1st Apr

1st Sep 180°

1st Jul 1st Aug

150°

75°

165°

345°

255° 1st Feb 1st Jan

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

330° 16

17

15

14

13

12

11

10

9

8

315°

7

240°

90° 1st Oct 15°

1st Nov 105°

30° 17

15

16

13

14

12

10

9

8

45°

1st Dec

7

120°

135°

195°

225°

135°

1st Jul

150°

210°

150°

75°

165°

195°

270°

345°

255° 1st Feb

17

15

16

14

13

12

11

10

9

8

7

240°

17

16

1st Sep

Apply with caution Applicable

180°

17

16

15

14

13

12

11

10

9

8

8

1st Sep 90° 1st Oct

15°

255° 105° 1st 1st FebNov

7

105°

30°

1st Jan 1st Dec 120° 240°

15

16

17

14

285° 1st May

210°

225°

10

9

8

1st Nov

7

1st Dec 120°

135°

1st Jul

150°

210°

165°

195°

165°

11

13

45°

60° 135°

195°

75° 1st Aug

150° 165°

1st Sep

NORTH SOUTH

Apply with caution Applicable

17

16

15

14

13

12

11

10

9

8

1st Dec 120°

135°

225°

150°

210° 195°

Not Applicable Not Applicable

North: This device is adequate to shade the building for most of the hot hours during the year. However, a pair of shallow vertical fins would enhance its performance. South: This device is effective to shade all of the critical hot hours during the year. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

HORIZONTAL slatted SHADING DEVICE Shading masks of building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.designhunter.net/vietnamese-cool-m11-house/

1st Nov

7

240°

165°

EAST WEST

105°

1st Jan

150° 180°

1st Oct

255° 1st Feb

135°

195°

North: This device is adequate to shade the building for most of the hot hours during the year. However, a pair of shallow vertical fins would enhance its performance. South: This device is effective to shade all of the critical hot hours during the year. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

9

225°

120°

210°

Not Applicable

10

240°

1st Dec

7

240°

225°

Not Applicable

11

75° 1st Aug

165°

90°

1st Mar N1st Oct

315°

1st Nov 105°

165°

EAST WEST

12

13

1st Jul

150°

1st Mar

1st Jan

1st Dec

150° 195°

14

60°

1st Apr

255° 1st Feb

135°

210°

15

45°

1st Oct

120°

225°

180° 1st Apr 1st Sep

330°

1st Jan

1st Mar 1st Nov 105°

1st Jan

1st Dec 120°

135°

Building Block (Ho Chi Minh city) 270°

1st Apr

1st Oct

255° 1st Feb

7

1st Jun

1st Aug

1st May 285°

210°

195°

30°

1st Nov

300°

285° 75° 1st May 1st Aug

210°

15°

105° 8

300°

60°

1st Jun

165°

1st Mar

NORTH SOUTH

11

9

1st Jul 1st Jun

1st Mar

120° 240°

225°

60° 225°

285° 1st May

1st Apr

1st MarN

10 315°

1st Jun

1st Sep

90° 1st Oct

270°

11

45°

300°

60°

Building Block (DA NANG)

12

13

14

330°

240°

1st Apr

270°

15

16

17

1st Jan

1st Oct

345° 30°

315°

45°

135°

1st 1st Jul Jun 1st Aug 1st May 285° 75°

210°

1st Sep

1st Apr

9

15°

255° 1st Feb

330°

30°

60° 300° 225°

1st Jun

1st Aug 210°

10 315°

300°

1st Jul

150°

11

345°

15°

1st Mar

120°

1st Mar

15°

17

13

14

195° 1st Sep

90° 1st Oct

N

12

45°

1st May 285°

60°

1st Jun

15

16

165°

120° 240°

1st May 285°

17

1st Jan

1st Nov 105°

330°

300°

1st Jul 75°

300° 225°

345° 30°

240°

150°

1st 1stDec Jan

7

15°

255° 1st Feb

315°

1st Aug

1st Nov 255° 105° 1st Feb

330°

16

45°

60°

180° 1st Sep

270°

1st Mar

330°

135°

Building Block (HA NOI) 1st Apr

17

345° 30°

300°

1stJul Jun 1st 1st Aug 1st May 285° 75°

1st Apr

1st Jan

15°

1st Dec

7

1st Sep

1st Oct

120°

1st May 285°

82

75° 1st Aug

1st Apr

1st Apr

1st Oct

240°

o

1st Jul

285° 1st May

75° 1st Sep

315°

VSA Angle = 56

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

30°

315°

300°

1st Jul

15°

330°

30°

315°

1st May 285°

N

345°

15°

330°

NORTH SOUTH

180°

165°

EAST Apply with caution WEST Apply with caution

Not Applicable Not Applicable

North: This device is adequate to shade the building for most of the hot hours during the year. The addition of a single vertical fin would enhance its performance. South: This device is adequate to shade most of the critical hot hours during the year. The addition of a single vertical fin would enhance its performance. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used.


CASE STUDY

05

83


CS 05

LE MON house Kuala Lumpur, Malaysia Tropical Wet Residential 176.5 m2 1.5 2 Fabian Tan

(1) Highly permeable facade along with ceiling fan allows for cross ventilation to occur.

(2) Vegetated terrace helps cool the roof, while deep overhang shades the internal spaces.

(3) Operable windows on higher level enhance cross ventilation in the building.

(4) Tall courtyard space allows for stack ventilation to occur within the building.

Building sectional diagram illustrated by Duy Vo - Photographic images and fl oor plans retrieved via http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

84


HA NOI

DA NANG

HO CHI MINH CITY

Open fl oor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit building’s occupants in Ha Noi, however during the cold period, caution must be taken.

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Apply with caution

Apply with caution

Applicable

LE MON house Kuala Lumpur, Malaysia Building Overview This 1.5-storey mid-terrace house was renovated to not only provide shelter to an old lady and her daughter but also to house their large private collection of Chinese antiques. Le Mon House’s architecture is driven by the emphasis on privacy, aesthetics & climate responsiveness. As a result, a central courtyard and a linear open plan protected by permeable yet solid facade elements are implemented.

Open floor plan for better ventilation The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Apply with caution

Similarly to Ha Noi, building’s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Applicable

permeable surfaces for better air flow Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants..

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

evaporative cooling via plants Photographic images retrieved via this link: http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

85


HA NOI Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the bathroom is located next to the vertical void, allowing moisture to be exhausted.

Applicable

DA NANG

HO CHI MINH CITY

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building.

Building’s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

Applicable

humidity relief via bathroom zoning Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the kitchen is next to an open void, allowing moisture from cooking to be driven out by stack ventilation.

Applicable

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building via stack ventilation.

Applicable

Building’s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

HUMIDITY RELIEF VIA KITCHEN ZONING On hot and windless day in Ha Noi, especially in the urban area, solar-induced stack ventilation enhances air movement, thus further cooling the interior spaces. However, caution must be taken in order to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, building’s occupants in Da Nang should benefit from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

SOLAR-INDUCED STACK VENTILATION Photographic images retrieved via http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

86

Building’s occupants in Ho Chi Minh City can benefit from this strategy. With low sky coverage throughout the year, this strategy should be easily employed. However, unwanted solar heat gain must be prevented at all cost.

Apply with caution

LE MON house Kuala Lumpur, Malaysia


HA NOI Natural daylight is brought inside using the overhead sun. However, shading strategy must be employed to prevent unwanted heat gain. In this case, horizontal slats are used to shade. Ha Noi would benefit from this strategy.

Applicable

DA NANG

HO CHI MINH CITY

LE MON house This strategy can benefit the buildings in Da Nang as it helps aleviate unwanted heat gain from the overhead sun.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the buildingâ&#x20AC;&#x2122;s occupants.

Kuala Lumpur, Malaysia

Applicable

SHADING OF OVERHEAD SUN Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

REFLECTIVE INTERNAL SURFACES Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT VIA OVERHEAD SUN Photographic images retrieved via http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

87


HA NOI

DA NANG

Due to the lack of significant diurnal swing, time-lag cooling via the use of thermal mass in building is neither applicable nor even feasible in the climate of Ha Noi.

Da Nang experiences a considerable diurnal swing for half of the year, thus the use of thermal mass in this climate may be of benefit. However, caution must be taken for the period where the diurnal swing is minimal.

Not Applicable

Apply with caution

HO CHI MINH CITY

LE MON house Ho Chi Minh City experiences significantly large diurnal swing during most months the year, therefore the use of thermal mass in this climate is highly beneficial.

Applicable

THERMAL MASS: CONCRETE Buildings in Ha Noi can benefit from having green roofs since they prevent the temperature conditions directly below the roof from rising due to solar heat gain during the hot months.

Applicable

Similarly to Ha Noi, buildings in Da Nang would also benefit from having vegetated roof since most of the year the temperatures remain consistently high.

Applicable

COOL VEGETATED ROOF

Photographic images retrieved via http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

88

Out of the 3 cities, a green roof would most benefit Ho Chi Minh City since the outdoor temperatures throughout the year remain consistently within the 21oC 38oC range.

Applicable

Kuala Lumpur, Malaysia


HA NOI The shading device of this building resembles the combined system of both an overhang and 2 vertical fins, or aka egg crate system. 1 of the side walls extends way beyond the overhang, thus shading completely one half of the window glazing. The other side wall’s length is equal to the overhang’s depth. The shading mask is illustrated accordingly.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jun

45°

1st Jul

1st Sep

1st Apr

1st Mar

15°

345°

255° 1st Feb

30°

1st Jan

315°

15

16

17

1st Nov 105°

330° 14

45°

12

13

11

10 315°

9

8

300°

60° 225°

1st Jun

210° 195°

270° 1st Mar

345°

255° 1st Feb 14

12

13

11

10 315°

9

8

240°

90° 1st Oct

90° 1st Oct 1st Nov 105°

30° 15

14

45°

12

13

11

10

9

8

7

210°

1st Dec 120°

135°

225°

195°

135°

150°

75°

165°

195°

1st Dec

7

1st Apr

1st Sep 180°

1st Jul 1st Aug

150°

75°

165°

345°

255° 1st Feb 1st Jan

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

330° 16

17

15

14

13

12

11

10

9

8

315°

7

240°

90° 1st Oct 1st Nov 105°

30° 17

15

16

13

14

12

135°

195°

9

8

1st Dec

7

270°

225°

150°

210° 195°

17

16

17

15

16

14

13

12

11

10

9

8

7

240°

1st Jan

1st Dec

Applicable Applicable

180°

17

16

14

13

12

11

10

9

8

225°

North: This device is effective to shade the building for all of the hot hours during the year. South: This device is effective to shade all of the critical hot hours during the year. East: This device fails to shade half of the hot hours during the year, thus ineffective. It, therefore, should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

12

13

11

1st Mar N1st Oct

9

8

1st Sep 90° 1st Oct

15°

255° 105° 1st 1st FebNov

330° 10

7

105°

30°

1st Jan 1st Dec 120° 240°

15

16

17

14

11

13

10

9

8

1st Nov

7

1st Dec 120°

45°

60°

285° 1st May

225°

135°

1st Jul

150°

195°

165°

210°

165°

195°

75° 1st Aug

1st Apr

1st Sep

1st Mar

1st Oct

NORTH SOUTH

255° 1st Feb

1st Dec

7

150° 165°

Applicable Applicable

180°

105°

1st Jan

17

16

14

13

12

11

10

9

8

225°

135°

210°

150° 195°

Not Applicable Not Applicable

North: This device is effective to shade the building for all of the hot hours during the year. South: This device is effective to shade all of the critical hot hours during the year. East: This device fails to shade half of the hot hours during the year, thus ineffective. It, therefore, should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

1st Nov

7

1st Dec 120°

165°

EAST WEST

15

240°

150° 195°

Not Applicable

14

210°

135°

210°

Not Applicable

75° 1st Aug

165°

90°

135°

120°

165°

EAST WEST

15

240°

150° 195°

15

225°

1st Nov 105°

255° 1st Feb

135°

210°

60°

150°

300°

1st Sep

45°

1st Oct

120°

225°

1st Dec 120°

135°

Building Block (Ho Chi Minh city)

240°

1st Mar

1st Jan

7

1st Jul

285° 75° 1st May 1st Aug 180°

315°

150°

30°

1st Nov

1st Jun

75°

165°

345°

1st Jan

135°

1st Jul

15°

105° 8

300°

270°

255° 1st Feb

120°

9

1st Apr 1st Sep

1st Apr

1st Nov 105°

255° 1st Feb

o

10

45°

1st Oct

HSA Angle = 56

210° 195°

1st Aug

1st May 285°

210°

285° 1st May

60°

1st Jun

165°

1st Mar

NORTH SOUTH

11

10

1st Jul 1st Jun

1st Mar

15°

120° 240°

225°

60° 225°

1st Apr

1st MarN

11

330°

315°

1st Jun

1st Sep

90° 1st Oct

270°

12

45°

300°

60°

Building Block (DA NANG)

13

14

240°

1st Apr

270°

17

1st Jan

1st Oct

345° 30° 15 16

315°

45°

135°

1st 1st Jul Jun 1st Aug 1st May 285° 75°

210°

1st Sep

1st Apr

8

15°

255° 1st Feb

330°

30°

60° 300°

1st Aug 210°

9

300°

1st Jul

150°

10 315°

225°

1st Jun

1st Mar

15°

16

11

345°

15°

1st Mar

120°

195° 1st Sep

17

12

13

14 45°

1st May 285°

60°

1st Jun

15

16

165°

120° 240°

1st May 285°

17

1st Jan

1st Nov 105°

330°

300°

1st Jul 75°

300° 225°

345° 30°

240°

150°

1st 1stDec Jan

7

15°

255° 1st Feb

315°

1st Aug

1st Mar N 1st Nov 255° 105° 1st Feb

330° 15

16

45°

60°

180° 1st Sep

270°

1st Mar

330°

135°

Building Block (HA NOI) 1st Apr

17

345° 30°

300°

1stJul Jun 1st 1st Aug 1st May 285° 75°

1st Apr

1st Jan

15°

120°

1st May 285°

1st Sep

1st Oct

1st Dec

7

240°

o

75° 1st Aug

1st Apr

1st Apr

1st Oct 345°

HSA Angle = 0

1st Jul

285° 1st May

75° 1st Sep

330°

VSA Angle = 61o

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

30°

315°

300°

1st Jul

15°

330°

30°

315°

1st May 285°

N

345°

15°

330°

NORTH SOUTH

180°

165°

EAST Apply with caution WEST

Applicable

Not Applicable Not Applicable

North: This device is effective to shade the building for all of the hot hours during the year. South: This device is adequate in this orientation since it is able to shade most of the hot hours during the year. However, internal shading device can be added to enhance its performance. East: This device can only shade the building for half of the amount of hot hours in the year; thus ineffective, therefore should not be used. West: This device is ineffective especially in this orientation, therefore should not be used.

HORIZONTAL OVERHANG Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.archdaily.com/241950/le-mon-writeup-fabian-tan/

89


CASE STUDY

90

06


CS 06

36 BTrd house Boon Teck Road Singapore Tropical Wet Residential 284.97 m2 3 + roof terrace Not Available DP Architects

(1) Sun space is located in between vertical slats and internal living space.

(2) Interior spaces are naturally lit and well-shaded by the plants and deep overhang.

(3) Open structure with full height sliding glass panels enhances cross ventilation.

(4) Refl ective roof surface & deep overhang help cool the roof against intense heat.

Building sectional diagram illustrated by Duy Vo - Photographic images, elevation drawings and sections retrieved via http://www.archdaily.com/199918/36-btrd-dp-architects/

91


HA NOI

DA NANG

HO CHI MINH CITY

Open fl oor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit building’s occupants in Ha Noi, however during the cold period, caution must be taken.

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Apply with caution

Apply with caution

Applicable

OPEN FLOOR PLAN FOR BETTER VENTILATION The addition of transitional spaces allows for the modulating of heat that enters the building. This strategy is of benefit to building’s occupants in the climate of Ha Noi.

Applicable

Similarly to Ha Noi, building’s occupants in Da Nang would benefit from this strategy especially during the hot period.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

HEAT MODULATING BUFFER SPACE The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Apply with caution

Similarly to Ha Noi, building’s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

PERMEABLE SURFACES FOR BETTER AIR FLOW Photographic images retrieved via http://www.archdaily.com/199918/36-btrd-dp-architects/

92

Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Applicable

36 BTrd house Boon Teck Road Singapore Building Overview This typical 3-storey plus roof terrace residential unit is designed to demonstrate a new sustainable housing solution that is acclimatized to the tropical climate of Singapore. The architecture of this 36 BTrd House is driven by the needs to achieve comfortable indoor environmental for the occupants. The overall building consists of an open structure masked by a vertical set of metal shades.


HA NOI

DA NANG

HO CHI MINH CITY

During the hot period in Ha Noi, having large openings in direction of the prevailing winds would be effective. However, they must be carefully shaded to avoid unwanted solar heat gain. Also, caution must be taken during the cold period.

Similarly to Ha Noi, this strategy can definitely be beneficial to the building’s occupants in Da Nang, especially during the hot period. Shading and reduction of infiltration must be implemented to avoid causing thermal discomfort.

Out of the 3 cities, building’s occupants in Ho Chi Minh City would benefit most from this strategy. However, shading of these large openings must be carefully executed to avoid unwanted solar heat gain.

Apply with caution

Apply with caution

36 BTrd house Boon Teck Road Singapore

Apply with caution

LARGE OPENINGS FOR BETTER VENTILATION Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants.

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS In the case of this building, the fl oor plate of 1st fl oor receded allowing for shading of the space below. Self-shading architecture is of benefit in the climate of Ha Noi since it prevents solar heat gain.

Apply with caution

Building’s occupants in Da Nang, similarly to Ha Noi, can benefit from this strategy since it prevents solar heat gain.

Applicable

Ho Chi Minh City would benefit most from this strategy since solar heat gain is a major concern for building’s occupants here.

Applicable

SELF-SHADING STRUCTURE Photographic images retrieved via http://www.archdaily.com/199918/36-btrd-dp-architects/

93


HA NOI Reflective colors keep the roof top cool, thus reducing cooling demand in the building. This strategy would be effective in the climate of Ha Noi.

Applicable

DA NANG

HO CHI MINH CITY

With a considerable amount of hot days during the year, this strategy would be effective in the climate of Da Nang.

With consistently intense sun in Ho Chi Minh City, refl ective colored roof top, as used in this building, is an effective means to prevent internal temperature increase.

Applicable

Applicable

reflective-colored roof top An open vertical staircase, heated from above by solar energy, induces air fl ow from within the buiding. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Solar-induced stack ventilation is an effective strategy in the climate of Da Nang. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

SOLAR-INDUCED STACK VENTILATION

Photographic images retrieved via http://www.archdaily.com/199918/36-btrd-dp-architects/

94

This strategy is effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

36 BTrd house Boon Teck Road Singapore


CASE STUDY

07

95


CS 07

3x9 house Ho Chi Minh City Vietnam Tropical Hot & Dry Residential 27 m2 2 2 A21 Studio

(1) Vertical wood slats are used to provide necessary shading for the interior.

(2) Minimally partitioned internal layout enhances air flow throughout the building.

(3) Overhead skylight allows natural daylight to enter the internal spaces.

(4) The metal screen invites daylight inside the kitchen while enhancing air fl ow

Building sectional diagram illustrated by Duy Vo - Photographic images and fl oor plans retrieved via http://www.archdaily.com/223340/3x9-house-a21-studio/

96


HA NOI

DA NANG

HO CHI MINH CITY

Refl ective colored external surfaces reduce cooling demand in Ha Noi by preventing the interior temperature conditions from rising due to direct solar heat gain.

Refl ective colored external surfaces reduce cooling demand in Da Nang by preventing the interior temperature conditions from rising due to direct solar heat gain.

With consistently intense sun in Ho Chi Minh City, white colored external surfaces, as used in this building, are an effective means to prevent internal temperature increase.

3x9 house

Applicable

Applicable

Applicable

Ho Chi Minh City Vietnam Building Overview This contemporary Vietnamese tube house, situated on a tiny urban lot in Ho Chi Minh City, was designed for 2 elderly clients. The architecture of this residence was driven by the desire to integrate nature deep into the internal living spaces. As a result, the residence features an open fl oor plan, a light overall structure, a glass roof top, a tree and permeable surfaces in order to create a nature-infused interior.

Reflective external surfaces Skylights are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Skylights are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Skylights are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT VIA OVERHEAD SUN Natural daylight is brought inside using the overhead sun. However, shading strategy must be employed to prevent unwanted heat gain. In this case, horizontal slats are used to shade. Ha Noi would benefit from this strategy.

Applicable

This strategy can benefit the buildings in Da Nang as it helps aleviate unwanted heat gain from the overhead sun.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the buildingâ&#x20AC;&#x2122;s occupants.

Applicable

SKYLIGHT SHADING TO AVOID OVERHEATING Photographic images retrieved via http://www.archdaily.com/223340/3x9-house-a21-studio/

97


HA NOI

DA NANG

Open floor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit building’s occupants in Ha Noi, however during the cold period, caution must be taken.

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Apply with caution

Apply with caution

HO CHI MINH CITY

3x9 house Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Applicable

Open floor plan for better ventilation Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the kitchen is zoned in the open, allowing moisture from cooking to be driven out by the cross ventilation.

Applicable

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building via cross ventilation.

Applicable

Building’s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

HUMIDITY RELIEF VIA VOID IN KITCHEN Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants.

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS Photographic images and exploded axonometric drawing retrieved via http://www.archdaily.com/223340/3x9-house-a21-studio/

98

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

Ho Chi Minh City Vietnam Axonometric View


HA NOI The shading device of the building consists of a series of evenly-spaced vertical wooden slats. Due to its vertical orientation, the device, as a whole, is categorized as vertical fins; thus its overall shading mask is illustrated accordingly. Speculations on the depth of the slat and the width of the gap in between slats were made based on photographic images of the device.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jul

75° 1st Aug

1st Apr

1st Apr

1st Oct 345°

1st Mar

345°

15°

255° 1st Feb

15

16

17

1st Nov 105°

330°

30°

1st Jan 315°

12

13

14

11

45°

240°

10 315°

9

8

345° 30°

1st May 285°

135°

210° 195°

75°

345°

1st Mar

90° 1st Oct 1st Mar N

1st Jan

17

15

16

14

11 315°10

12

13

15°

1st Nov 255° 105° 1st Feb

330°

255° 1st Feb

90° 1st Oct

9

8

1st Jan 1st Dec 240° 120°

7

240°

1st Nov 105°

30° 15

16

17

14

45°

10

9

8

7

1st Dec

225°

135°

1st May 285°

1st Apr

210°

195°

150°

75° 195°

165°

1st Jul

180° 1st Sep

165°

270° 1st Mar

345°

1st Jan

16

17

15

14

13

12

11

10 315°

9

8

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

7

240°

1st Nov 105°

30°

17

15

16

14

45°

13

12

11

10

9

8

1st Dec

7

120°

135°

165°

150°

75°

210°

165°

1st Sep

195°

150°

345°

1st Jan

17

16

1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

180°

17

16

15

14

13

12

11

10

9

8

11

10

9

8

75° 1st Aug

165°

1st Sep

90°

N 1st Mar 1st Oct

90° 15°

1st Oct 30°

255° 105° 1st 1st FebNov

7

1st Jan 1st Dec 120° 240°

15

16

17

105° 14

225°

10

9

8

1st Nov

7

1st Dec 120°

135°

1st Jul

150°

195°

165°

11

13

45°

60° 135°

285° 1st May

210°

75° 1st Aug

210°

165°

195°

150° 165°

1st Sep

NORTH SOUTH

17

16

15

14

13

12

11

10

9

8

135°

210°

150° 195°

Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used West: Similarly to the East orientation, this device is ineffective, therefore should not be used.

7

240°

225°

Not Applicable

1st Nov 1st Dec 120°

165°

EAST Apply with caution WEST Applicable

105°

1st Jan

135°

180°

1st Oct

255° 1st Feb

150° 195°

North: This device is an effective shading strategy for the building during all the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used.

12

13

1st Jun

120°

210°

Not Applicable

14

225°

1st Dec

7

240°

225°

Not Applicable

Building Block (Ho Chi Minh city)

240°

1st Nov 105°

165°

EAST Apply with caution WEST

Applicable

60°

150°

1st Mar

1st Jan

1st Dec

150° 195°

45°

135°

1st Apr

255° 1st Feb

135°

210°

1st Dec 120°

1st Oct

120°

225°

15

315°

1st Apr

1st Nov 105°

255° 1st Feb

7

1st Jul

285° 75° 1st May 1st Aug 180°

330°

255° 1st Feb

1st Mar

1st Mar

30°

1st Nov

300° 135°

1st Jul

15° 105°

8

300°

270°

1st Aug

1st May 285° 195°

225°

330°

9

1st Apr 1st Sep

60°

1st Jun

210°

195°

1st Mar

15°

120° 240°

225°

210°

270°

90° 1st Oct

10

1st Jul 1st Jun

1st Apr

90° 1st Oct N 1st Mar

330°

255° 1st Feb

225°

1st Sep

270°

11

315°

60°

285° 1st May

75°

12

45°

1st Jun

1st Aug

150°

13

14

240°

300°

60°

1st Oct

NORTH SOUTH

315°

45°

120°

1st Apr

1st Sep

1st Apr

7

345° 30° 15 16

17

1st Jan

135°

Building Block (DA NANG)

15° 255° 1st Feb

330°

30°

1st Dec

300° 135°

1st Jul

150°

8

1st Aug 1st May 285° 75°

210°

1st Aug

1st May 285°

9

1st Oct

345°

15°

1st 1st Jul Jun

60°

1st Jun

210°

11

120°

300° 225°

12

13

10

60° 300°

225°

195°

270°

270°

11

315°

1st Jun

1st Sep

1st Sep

12

13

14 45°

165°

180°

Building Block (HA NOI) 1st Apr

17

15

16

1st Nov 105°

330°

240°

300°

1st Jul

150°

75°

1st Apr

315°

1st Aug

1st May 1st Aug 285°

345° 30°

1st Jan

45°

60°

60° 1st Jun 1st Jul

225°

15° 255° 1st Feb

330°

300°

300°

1st Mar

1st Mar

15°

1st Dec

7

1st Sep

1st Oct

120°

1st Jun

HSA Angle = 34o

1st Jul

285° 1st May

75° 1st Sep

1st Sep

1st Apr

330°

HSA Angle = 34o

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

1st May 285°

30°

315°

45°

300°

1st Jul

15°

330°

30°

315°

1st Jun

N

345°

15°

330°

NORTH SOUTH

180°

165°

EAST Apply with caution WEST Applicable

Not Applicable Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used West: Similarly to the East orientation, this device is ineffective, therefore should not be used.

VERTICALLY-SLATTED SHADING DEVICE Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.archdaily.com/223340/3x9-house-a21-studio/

99


CASE STUDY

100

08


CS 08

LUCKY SHOP HOUSE Singapore City - Singapore Tropical Wet Residential N/A 2 + back extension 2 CHANG Architects

(1) Open plan with minimum amount of partition walls maximizes internal air fl ow.

(2) Ceiling fan assists with cross ventilation in the double height interior space.

(3) Full height sliding glass panels, once opened, expose the inside to the outside.

(4) Staggered walls create vertical apertures for natural ventilation and daylight.

Building sectional diagram illustrated by Duy Vo - Photographic images and building fl oor plans retrieved via http://www.archdaily.com/320233/lucky-shophouse-chang-architects/

101


HA NOI

DA NANG

The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Similarly to Ha Noi, buildingâ&#x20AC;&#x2122;s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

Apply with caution

HO CHI MINH CITY

LUCKY SHOP HOUSE Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Applicable

permeable surfaces for better air flow Open fl oor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit buildingâ&#x20AC;&#x2122;s occupants in Ha Noi, however during the cold period, caution must be taken.

Apply with caution

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Apply with caution

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Applicable

open floor plan for better ventilation Natural daylight is effective in reducing electric lighting load within the building in the climate of Ha Noi. However, designers must avoid or eliminate unwanted solar heat gain.

Apply with caution

Natural daylight is effective in reducing electric lighting load within the building in the climate of Da Nang. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

invite natural daylight inside Photographic images retrieved via http://www.archdaily.com/320233/lucky-shophouse-chang-architects/

102

Natural daylight is effective in reducing electric lighting load within the building in the climate of Ho Chi Minh. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Singapore City - Singapore Building Overview This Singaporean shop house, formerly a bookstore called The Lucky Book Store, was renovated to accommodate living space for a couple. The architecture of this residence was driven by the desire to convert the existing shop house into a dwelling place that also has a fl exible communal space . The overall structure of the old book store was kept intact and exposed while the extension was one-storey high.


HA NOI

DA NANG

HO CHI MINH CITY

Refl ective colored external surfaces reduce cooling demand in Ha Noi by preventing the interior temperature conditions from rising due to direct solar heat gain.

Refl ective colored external surfaces reduce cooling demand in Da Nang by preventing the interior temperature conditions from rising due to direct solar heat gain.

With consistently intense sun in Ho Chi Minh City, white colored external surfaces, as used in this building, are an effective means to prevent internal temperature increase.

Applicable

Applicable

LUCKY SHOP HOUSE Singapore City - Singapore

Applicable

Light-colored external surfaces Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

LIGHT-COLORED INTERNAL SURFACES A lush green garden, located centrally on the site, cools the air that breezes through the site. This strategy would be of benefit in the climate of Ha Noi during the hot season.

Apply with caution

Similarly to Ha Noi, buildings in Da Nang can also benefit from the green lush garden during the hot period of the year.

Applicable

This strategy would be of the utmost benefit for Ho Chi Minh City since the temperature conditions remain high throughout the whole year.

Applicable

centrally located LUSH Garden Photographic images retrieved via http://www.archdaily.com/320233/lucky-shophouse-chang-architects/

103


CASE STUDY

104

09


CS 09

NHA BEO HOUSE Ho Chi Minh City - Vietnam Tropical Wet & Dry Residential 238 m2 4 4 Trinhvieta - Architects

(1) Closely spaced horizontal slats protect the internal spaces from the intense sun.

(2) Triple height courtyard dampens outside noise and further cools the inside.

(3) Internal spaces are exposed to greater natural ventilation due to permeable facade.

(4) Interior spaces are naturally lit yet shaded from intense solar radiation.

Building sectional diagram illustrated by Duy Vo - Photographic images and fl oor plans retrieved via http://www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/

105


HA NOI Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

DA NANG

HO CHI MINH CITY

NHA BEO HOUSE This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

REFLECTIVE INTERNAL SURFACES The introduction of courtyards in the building allows for stack ventilation to take place. This strategy is of benefit in Ha Noi. However, caution must be taken to avoid unwanted solar heat gain.

Apply with caution

Similarly to Ha Noi, building’s occupants in Da Nang should benefit greatly from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Apply with caution

Building’s occupants in Ho Chi Minh City can benefit from the enhanced internal air movement due to stack ventilation via the courtyard. However, unwanted solar heat gain from above must be prevented at all cost.

Apply with caution

solar-induced COURTYARD STACK Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants..

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS Photographic images retrieved via http://www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/

106

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

Ho Chi Minh City Vietnam Building Overview This tube house, located on a 4-meter-by-20-meter lot, is designed to maximize the interaction between the interior & the outdoor via the introduction of an “intermediate space” that connects to other functional spaces. This said space is either a courtyard, an open void or a semi-open space situated in the vicinity of other living spaces. It enhances natural air movement and invites daylight.


HA NOI

DA NANG

The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Similarly to Ha Noi, building’s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

Apply with caution

HO CHI MINH CITY

NHA BEO HOUSE Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Ho Chi Minh City Vietnam

Applicable

PERMEABLE SURFACES FOR BETTER AIR FLOW Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Apply with caution

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

NATURAL DAYLIGHT FROM OVERHEAD SUN The addition of transitional spaces allows for the modulating of heat that enters the building. This strategy is of benefit to building’s occupants in the climate of Ha Noi.

Applicable

Similarly to Ha Noi, building’s occupants in Da Nang would benefit from this strategy especially during the hot period.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

HEAT MODULATING BUFFER SPACE Photographic images retrieved via http://www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/

107


HA NOI The shading device of this building consists of a series of evenly-spaced horizontal slats. Due to its horizontal orientation, the device is categorized as an overhang, thus its shading mask is illustrated accordingly and similarly to that of an overhang. Speculations on depth of slats and in-between slat gap were made based on photographic images of the building.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jul

345°

345°

15°

255° 1st Feb

15

16

17

12

13

14

10 315°

9

8

15°

1st May 285°

45°

195° 1st Apr 270° 345°

1st Mar

15

16

14

11 315°10

12

13

8

75°

1st Sep

270°

90° 1st Oct N

90° 1st Oct 15°

1stDec Jan 1st

7

1st Nov 105°

15

16

17

1445°

12

13

11

10

9

8

7

120°

120° 240°

240°

1st Jun

1st May 285°

1st Apr

135°

195°

75°

210° 195°

165°

150°

60°

135°

1st Jul

Building Block (DA NANG) 180° 1st Sep

1st Aug

150°

75°

165°

270° 345°

1st Jan

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

330°

255° 1st Feb 16

17

15

14

13

12

11

10 315°

9

8

7

240°

90° 1st Oct 1st Nov 105°

30°

17

15

16

14

45°

13

12

10

9

8

1st Dec

7

120°

135°

1st Jun

165°

195°

210°

285° 1st May

195°

75°

210°

165°

1st Sep

195°

270° 345°

1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

Apply with caution Applicable

180°

17

1st Jan

16

17

16

15

14

13

12

11

10

9

8

12

13

11

10

9

8

1st Sep 90° 15°

1st Oct 30°

255° 105° 1st 1st FebNov

7

1st Jan 1st Dec 120° 240°

15

16

17

105° 14

285° 1st May

210°

150°

225°

10

9

8

1st Dec 120°

135°

75° 1st Aug

210°

165°

150° 165°

195° 1st Sep

NORTH SOUTH

Apply with caution Applicable

16

14

13

12

11

10

9

8

135°

195°

Not Applicable

7

150°

210°

Not Applicable

1st Nov 1st Dec 120°

225°

165°

EAST WEST

105° 17

15

240°

135°

180°

1st Oct

255° 1st Feb 1st Jan

NORTH SOUTH

North: This device is adequate to shade the building for most of the hot hours during the year. The addition of a single vertical fin would enhance its performance. South: This device is effective to shade all of the critical hot hours during the year. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

HORIZONTALly- slatted SHADING DEVICE Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://www.archdaily.com/387096/nhabeo-house-trinhvieta-architects/

1st Nov

7

1st Jul

150°

195°

165°

11

13

45°

60° 135°

1st Jun

150° 195°

North: This device is adequate to shade the building for most of the hot hours during the year. However, a pair of shallow vertical fins would enhance its performance. South: This device is effective to shade all of the critical hot hours during the year. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used for this particular orientation.

14

225°

120°

210°

Not Applicable

75° 1st Aug

165°

90°

N 1st Mar 1st Oct

240°

1st Dec

7

240°

225°

Not Applicable

15

315°

1st Nov 105°

165°

EAST WEST

Building Block (Ho Chi Minh city)

1st Mar

1st Jan

1st Dec

150° 195°

150°

1st Apr

255° 1st Feb

135°

210°

60°

135°

1st Oct

120°

225°

45°

1st Jul

285° 75° 1st May 1st Aug 180°

330°

255° 1st Feb

1st Apr

1st Nov 105°

255° 1st Feb

30°

1st Dec 120°

300°

270°

1st Mar

1st Mar

7

300° 135°

1st Jul

150°

105° 8

1st Nov

1st Apr 1st Sep

1st Aug

1st May 285°

210°

225°

330°

9

1st Jul 1st Jun

60°

1st Oct

NORTH SOUTH

11

120° 240°

225°

225°

1st Jun

1st Mar

15°

10 315°

60°

1st Apr

90° 1st Oct N 1st Mar

11

45°

1st Sep

270°

12

13

14

240°

300°

1st Apr

1st Sep

1st Apr

315°

45°

120°

30° 15 16

17

1st Jan

15°

345°

255° 1st Feb

330°

30°

1st Dec

7

300°

1st Jul

150°

8

1st Aug 1st May 285° 75°

210°

1st Aug

1st May 285°

210°

225°

135°

9

1st Oct 15°

345°

15°

1st 1st Jul Jun

60°

300° 225°

1st Dec

10

60° 300°

225°

1st Mar 30°

11

315°

1st Jun

195°

1st Sep

12

13

14 45°

165°

180°

1st Nov 255° 105° 1st Feb

9

1st Aug

150°

1st Apr

1st Mar

17

15

16

1st Nov 105°

330°

240°

300°

1st Jul

Building Block (HA NOI)

330°

255° 1st Feb

315°

60°

345° 30°

1st Jan

1st Dec

7

135°

1st Aug 1st May 285° 75°

210°

15° 255° 1st Feb

330°

Jun 1st1stJul

17

1st Mar

345° 30°

120°

300°

60°

225°

1st Jun

1st Jan

11

45°

240°

300°

1st Nov 105°

330°

30°

1st Sep

1st Oct 1st Mar

1st Mar

1st Jan

108

75° 1st Aug

1st Apr

1st Apr

1st Oct

315°

o

1st Jul

285° 1st May

75° 1st Sep

1st Sep

1st Apr

330°

VSA Angle = 45

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

1st May 285°

30°

315°

45°

300°

1st Jul

15°

330°

30°

315°

1st Jun

N

345°

15°

330°

180°

165°

EAST Apply with caution WEST Apply with caution

Not Applicable Not Applicable

North: This device is adequate to shade the building for most of the hot hours during the year. The addition of a single vertical fins would enhance its performance. South: This device is adequate to shade most of the critical hot hours during the year. The addition of a single vertical fin would enhance its performance East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used.


CASE STUDY

10

109


CS 10

The NEST HOUSE Binh Duong - Vietnam Tropical Wet & Dry Residential 40 m2 2 2 A21 Studio

(1) Screens used on the facade maximizes air fl ow into the internal spaces of building.

(2) Shuttered windows are used for to take advantage & protect against sun & wind.

(3) Living spaces are located on stilts, opening up ground fl oor fully to natural ventilation

(4) The backyard opens up to the sky, thus conducive to enhancing air movement.

Building sectional diagram illustrated by Duy Vo - Photographic images, fl oor plans retrieved via http://www.archdaily.com/381335/the-nest-a21studio/

110


HA NOI

DA NANG

Refl ective colored external surfaces reduce cooling demand in Ha Noi by preventing the interior temperature conditions from rising due to direct solar heat gain.

Refl ective colored external surfaces reduce cooling demand in Da Nang by preventing the interior temperature conditions from rising due to direct solar heat gain.

Applicable

Applicable

HO CHI MINH CITY

The NEST HOUSE With consistently intense sun in Ho Chi Minh City, white colored external surfaces, as used in this building, are an effective means to prevent internal temperature increase.

Applicable

Binh Duong - Vietnam Building Overview The Nest, situated on a 40-square-meter lot, is built on a constraint budget. The building consists of steel frame structure cladded with corrugated metal sheets and enclosed within a white metal mesh. The architect & building owner wanted the building to be open with minimal amount of partition walls especially on the ground level, allowing for an abundance of natural light & natural ventilation.

REFLECTIVE EXTERNAL SURFACES Ha Noi has consistently high humidity levels throughout the year, thus evaporative cooling via plant’s evapotranspiration would not be of benefit. It will most likely exarcerbate the thermal stress on building’s occupants..

Not Applicable

Due to its adjacency to the East Sea, Da Nang experiences high humidity levels most of the year, thus evaporative cooling is beneficial. However, during a few dry months of the year, Da Nang can benefit from this.

Apply with caution

Plants’ evapotranspiration coupled with winds entering from the front facade effectively cools building during the dry and hot period in Ho Chi Minh City. However, caution must be taken when humidity levels are high.

Apply with caution

EVAPORATIVE COOLING VIA PLANTS Open fl oor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit building’s occupants in Ha Noi, however during the cold period, caution must be taken.

Apply with caution

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Apply with caution

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Applicable

OPEN FLOOR PLAN FOR BETTER AIR FLOW Photographic images retrieved via http://www.archdaily.com/381335/the-nest-a21studio/

111


HA NOI

DA NANG

Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the kitchen is zoned in the open, allowing moisture from cooking to be driven out by the cross ventilation.

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building via cross ventilation.

Applicable

Applicable

HO CHI MINH CITY

The NEST HOUSE Buildingâ&#x20AC;&#x2122;s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

HUMIDITY RELIEF VIA kitchen zoning Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

Applicable

REFLECTIVE INTERNAL SURFACES Window shutters not only block the intense sun but also allow air fl ow to seep in. Ha Noi can definitely benefit from this strategy during the hot period, however, caution must be taken especially with infiltration in the winter.

Apply with caution

Similarly to Ha Noi, buildingâ&#x20AC;&#x2122;s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

SHUTTERED OPENING FOR LIGHT & SHADE Photographic images retrieved via http://www.archdaily.com/381335/the-nest-a21studio/

112

Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature conditions remain high and the sun remains intense throughout the year.

Applicable

Binh Duong - Vietnam


HA NOI

DA NANG

The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Similarly to Ha Noi, building’s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

Apply with caution

HO CHI MINH CITY

The NEST HOUSE Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Binh Duong - Vietnam

Applicable

PERMEABLE SURFACES FOR BETTER AIR FLOW In the case of this building, with the living quarter literally locating on stilts, the ground fl oor remains fully shaded. Self-shading architecture is of benefit in the climate of Ha Noi since it prevents solar heat gain.

Applicable

Building’s occupants in Da Nang, similarly to Ha Noi, can benefit from this strategy since it prevents solar heat gain.

Applicable

Ho Chi Minh City would benefit most from this strategy since solar heat gain is a major concern for building’s occupants here.

Applicable

Self-shading architecture Due to the consistently high levels of humdity in Ha Noi, it is important to avoid adding more moisture to the air. In this case, the bathroom is located next to the vertical void, allowing moisture to be exhausted.

Applicable

Similarly Ha Noi, Da Nang experiences high levels of humidity for most of the year. This strategy will be of benefit in the climate of Da Nang, as it effectively exhausts moisture out of the building.

Applicable

Building’s occupants in Ho Chi Minh City can benefit greatly from this strategy as the climate of this city has high levels of humidity, similarly to that of both Ha Noi and Da Nang.

Applicable

HUMIDITY RELIEF VIA BATHROOM ZONING Photographic images retrieved via http://www.archdaily.com/381335/the-nest-a21studio/

113


CASE STUDY

114

11


CS 1011

The DA NEST & A House HOUSE Binh HaDuong Noi - Vietnam - Vietnam Humid Subtropical Live Work 371 m2 5 + Roof Terrace N/A DA & A Architects

(1) Operable wood screens are conducive to both shading and pulling air in for ventilation.

(2) Vegetated sun space further separates the internal space from the intense sun.

(3) Full height sliding glass panels, once fully opened, invite both light and air inside.

(4) The staircase is integrated into the stack that is used to induce natural ventilation.

Building sectional diagram illustrated by Duy Vo - Photographic images, fl oor plans and elevation drawing retrieved via http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html

115


HA NOI

DA NANG

HO CHI MINH CITY

During the hot period in Ha Noi, having large openings in direction of the prevailing winds would be effective. However, they must be carefully shaded to avoid unwanted solar heat gain. Also, caution must be taken during the cold period.

Similarly to Ha Noi, this strategy can definitely be beneficial to the building’s occupants in Da Nang, especially during the hot period. Shading and reduction of infiltration must be implemented to avoid causing thermal discomfort.

Out of the 3 cities, building’s occupants in Ho Chi Minh City would benefit most from this strategy. However, shading of these large openings must be carefully executed to avoid unwanted solar heat gain.

Apply with caution

Apply with caution

Apply with caution

LARGE OPENINGS FOR BETTER VENTILATION The addition of transitional spaces allows for the modulating of heat that enters the building. This strategy is of benefit to building’s occupants in the climate of Ha Noi.

Applicable

Similarly to Ha Noi, building’s occupants in Da Nang would benefit from this strategy especially during the hot period.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

HEAT modulating BUFFER SPACE The building has permeable surfaces enhancing air movement through the building. This strategy can be applied in Ha Noi during the hot period, however caution must be taken during the cold period.

Apply with caution

Similarly to Ha Noi, building’s occupants can benefit from this strategy during the hot period. However, during the short cold period, caution must be taken due to infiltration.

Apply with caution

PERMEABLE SURFACES FOR BETTER AIR FLOW Photographic images retrieved via http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html

116

Out of the 3 cities, Ho Chi Minh City would benefit most from this strategy since the temperature remains consistenly high throughout the year.

Applicable

The DA NEST & A House HOUSE Binh HaDuong Noi - Vietnam - Vietnam Building Overview This 5-storey, single family tube house in Ha Noi is designed to accommodate the client’s desire for a live-work space. The architecture is driven by the emphasis on privacy, functional uses of space & climate responsiveness. DA&A house consists of a cast-in-place reinforced concrete structure that is cladded with an operable wood screen system for fl exible shading options and added security.


HA NOI

DA NANG

HO CHI MINH CITY

On hot and windless day in Ha Noi, especially in the urban area, solar-induced stack ventilation enhances air movement, thus further cooling the interior spaces. However, caution must be taken in order to avoid unwanted solar heat gain.

Similarly to Ha Noi, building’s occupants in Da Nang should benefit from this strategy since the temperatures throughout the year remain mostly above 21oC. Caution must also be taken to avoid unwanted solar heat gain.

Building’s occupants in Ho Chi Minh City can benefit from this strategy. With low sky coverage throughout the year, this strategy should be easily employed. However, unwanted solar heat gain must be prevented at all cost.

Apply with caution

Apply with caution

The DA NEST & A House HOUSE Binh HaDuong Noi - Vietnam - Vietnam

Apply with caution

SOLAR-INDUCED STACK VENTILATION In the case of this building, the fl oor plate of 1st fl oor receded allowing for shading of the space below. Self-shading architecture is of benefit in the climate of Ha Noi since it prevents solar heat gain.

Applicable

Building’s occupants in Da Nang, similarly to Ha Noi, can benefit from this strategy since it prevents solar heat gain.

Applicable

Ho Chi Minh City would benefit most from this strategy since solar heat gain is a major concern for building’s occupants here.

Applicable

SELF-SHADING ARCHITECTURE Buildings in Ha Noi can benefit from having green roofs since they prevent the temperature conditions directly below the roof from rising due to solar heat gain during the hot months.

Applicable

Similarly to Ha Noi, buildings in Da Nang would also benefit from having vegetated roof since most of the year the temperatures remain consistently high.

Applicable

Out of the 3 cities, a green roof would most benefit Ho Chi Minh City since the outdoor temperatures throughout the year remain consistently within the 21oC 38oC range.

Applicable

VEGETATED ROOF TOP Photographic images retrieved via http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html

117


HA NOI The shading device of this building consists of a series of vertically slatted panels. Due to the vertical orientation, the device’s shading mask is illustrated to have 2 cut-off angles, similarly to those of the vertical fins. Speculations on the depth of the slat and the width of the gap in between slats were made based on photographic images of the device.

N

345°

DA NANG 15°

N

345°

330°

30°

HO CHI MINH CITY

315°

45°

300°

60°

1st Jun

45°

1st Jul

1st Sep

1st Apr

1st Mar

15°

345°

255° 1st Feb

30°

1st Jan

315°

15

16

17

1st Nov 105°

330° 14

45°

12

13

11

10 315°

9

8

300°

60° 225°

1st Jun

210° 195°

270° 1st Mar

345°

255° 1st Feb

1st Mar

15

14

12

13

11 315°10

9

8

240°

90° 1st Oct 1st Nov 105°

30°

15

16

12

14 45° 13

11

10

9

8

7

210°

1st Dec 120°

135°

225°

195°

135°

150°

75°

165°

195°

1st Dec

7

1st Apr

1st Sep 180°

1st Jul 1st Aug

150°

75°

165°

345°

255° 1st Feb 1st Jan

1st Nov 255° 105° 1st Feb 1st Dec 1st Jan

330° 16

17

15

14

13

12

11

10

9

8

315°

7

240°

90° 1st Oct 15°

1st Nov 105°

30° 17

15

16

13

14

12

135°

195°

210° 195°

10

9

8

45°

1st Dec

7

225°

150°

210° 195°

16

1st Sep

17

15

16

14

13

12

11

10

9

8

7

240°

Applicable Apply with caution

180°

17

16

15

14

13

12

11

10

9

8

11

10

9

8

90° 1st Oct

15°

255° 105° 1st 1st FebNov

7

105°

30°

1st Jan 1st Dec 120° 240°

15

16

17

14

225°

10

9

8

1st Nov

7

1st Dec 120°

135°

1st Jul

150°

195°

165°

11

13

45°

60°

285° 1st May

210°

210°

165°

195°

75° 1st Aug

150° 165°

1st Sep

NORTH SOUTH

17

16

15

14

13

12

11

10

9

8

1st Dec 120°

225°

135°

210°

150° 195°

Not Applicable Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used West: Similarly to the East orientation, this device is ineffective, therefore should not be used.

VERTICALLY-SLATTED SHADING DEVICE Shading masks for building’s 4 cardinal directions illustrated by Duy Vo - Photographic images retrieved via http://sgtt.vn/Kien-truc-doi-song/Chi-tiet/172942/Tu-nhien.html

1st Nov

7

240°

165°

EAST Apply with caution WEST

Applicable

105°

1st Jan

150° 180°

1st Oct

255° 1st Feb

135°

195°

North: This device is an effective shading strategy for the building during all the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used. West: Similarly to the East orientation, this device is ineffective, therefore should not be used.

12

13

135°

120°

210°

Not Applicable

14

225°

1st Dec

7

240°

225°

Not Applicable

15

1st Sep

90°

1st Mar N1st Oct

240°

1st Nov 105°

165°

EAST WEST

75° 1st Aug

165°

1st Mar

1st Jan

1st Dec

150° 195°

150°

1st Apr

255° 1st Feb

135°

210°

60°

1st Oct

120°

225°

45°

135°

Building Block (Ho Chi Minh city)

315°

1st Mar 1st Nov 105°

1st Jan

1st Dec 120°

1st Jul

285° 75° 1st May 1st Aug 180°

330° 17

1st Apr

1st Oct

255° 1st Feb

7

300°

150°

30°

1st Nov

1st Jun

75°

165°

345°

1st Jan

135°

1st Jul

15°

105° 8

300°

270°

255° 1st Feb

120°

9

1st Apr 1st Sep

270°

1st Aug

1st May 285°

210°

285° 1st May

60°

1st Jun

165°

1st Mar

NORTH SOUTH

11

10

1st Jul 1st Jun

1st Mar

120° 240°

225°

60° 225°

1st Apr

1st MarN

11

330°

315°

1st Jun

1st Sep

90° 1st Oct

270°

12

45°

300°

60°

Building Block (DA NANG)

13

14

240°

1st Apr

270°

17

1st Jan

1st Oct

345° 30° 15 16

315°

45°

135°

1st 1st Jul Jun 1st Aug 1st May 285° 75°

210°

1st Sep

1st Apr

8

15°

255° 1st Feb

330°

30°

60° 300°

1st Aug 210°

9

300°

1st Jul

150°

10 315°

225°

1st Jun

1st Mar

15°

17

11

345°

15°

1st Mar

120°

195° 1st Sep

90° 1st Oct

N

12

13

14 45°

1st May 285°

60°

1st Jun

15

16

165°

120° 240°

1st May 285°

17

1st Jan

1st Nov 105°

330°

300°

1st Jul 75°

300° 225°

345° 30°

240°

150°

1st 1stDec Jan

7

15°

255° 1st Feb

315°

1st Aug

1st Nov 255° 105° 1st Feb

330°

16

45°

60°

180° 1st Sep

270°

1st Mar

330°

135°

Building Block (HA NOI) 1st Apr

17

345° 30°

300°

1stJul Jun 1st 1st Aug 1st May 285° 75°

1st Apr

1st Jan

15°

120°

1st May 285°

1st Sep

1st Oct

1st Dec

7

240°

118

75° 1st Aug

1st Apr

1st Apr

1st Oct 345°

HSA Angle = 45o

1st Jul

285° 1st May

75° 1st Sep

330°

HSA Angle = 45o

60°

1st Jun

1st Aug

1st May 285°

75°

45°

300°

60°

1st Jun

1st Aug

30°

315°

300°

1st Jul

15°

330°

30°

315°

1st May 285°

N

345°

15°

330°

NORTH SOUTH

180°

165°

EAST Apply with caution WEST

Applicable

Not Applicable Not Applicable

North: This device is an effective shading strategy for the building during most of the hours where the building is exposed to direct solar gain. South: This device shades the building for the majority of hours during the year. A short overhang can be added to help completely shade the building. East: This device can only shade the building for a small percentage of time in the year; thus ineffective, therefore should not be used West: Similarly to the East orientation, this device is ineffective, therefore should not be used.


CASE STUDY

12

119


CS 12

THE POOL SHOP HOUSE Singapore City - Singapore Tropical Wet & Dry Residential 366.94 m2 4 N/A FARM with KD Architects

(1) Front facade with windows to allow for cross ventilation to occur within the building.

(2) Fully shaded pool conductively cools the interior spaces of the building.

(3) Wood slats added below skylight reduce solar heat gain while still providing daylight.

(4) Operable louvers allow for fl exibility in providing ventilation and natural daylight.

Building sectional diagram illustrated by Duy Vo - Photographic images, fl oor plans retrieved via http://www.thelor24ashophouseseries.com/21.htm

120


HA NOI

DA NANG

HO CHI MINH CITY

Light wells are effective in bringing natural daylight into the building in the climate of Ha Noi. However, practitioners must avoid or eliminate unwanted solar heat gain.

Light wells are effective in Da Nang since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Light wells are effective in Ho Chi Minh City since there is an abundance of sunlight from overhead. However, it is important to invite daylight in & avoid unwanted solar heat gain.

Apply with caution

Apply with caution

Apply with caution

THE POOL SHOP HOUSE Singapore City - Singapore Building Overview Provided with an opportunity to renovate an existing shop house, FARM with KD Architects decided to emphasize the linear typology of the building while celebrating the matrimony of the new and the old. The architecture of the Pool Shop House, as a result, has not only elements such as the monolithic lap pool to compliment the linearity but also components to enhance the indoor environmental quality.

Natural daylight from overhead sun Refl ective colored external surfaces reduce cooling demand in Ha Noi by preventing the interior temperature conditions from rising due to direct solar heat gain.

Applicable

Refl ective colored external surfaces reduce cooling demand in Da Nang by preventing the interior temperature conditions from rising due to direct solar heat gain.

Applicable

With consistently intense sun in Ho Chi Minh City, white colored external surfaces, as used in this building, are an effective means to prevent internal temperature increase.

Applicable

reflective external surfaces Open fl oor plan enhances air movement across the building. This helps cooling the internal spaces . This strategy can certainly benefit buildingâ&#x20AC;&#x2122;s occupants in Ha Noi, however during the cold period, caution must be taken.

Apply with caution

Da Nang can also benefit from this strategy since the temperatures throughout the year remain high. However, during the short cold period of the year, caution must also be taken.

Apply with caution

Out of the 3 cities, Ho Chi Minh City would benefit the most from this strategy since the temperature conditions remain consistently within the 21oC - 38oC range.

Applicable

OPEN FLOOR PLAN FOR BETTER VENTILATION Photographic images and building site plan retrieved via http://www.thelor24ashophouseseries.com/21.htm

121


HA NOI The addition of transitional spaces allows for the modulating of heat that enters the building. This strategy is of benefit to building’s occupants in the climate of Ha Noi.

Applicable

DA NANG

HO CHI MINH CITY

THE POOL SHOP HOUSE Similarly to Ha Noi, building’s occupants in Da Nang would benefit from this strategy especially during the hot period.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

HEAT MODULATING BUFFER SPACE Natural daylight is brought inside using the overhead sun. However, shading strategy must be employed to prevent unwanted heat gain. In this case, horizontal slats are used to shade. Ha Noi would benefit from this strategy.

Applicable

This strategy can benefit the buildings in Da Nang as it helps aleviate unwanted heat gain from the overhead sun.

Applicable

Ho Chi Minh City, out of the 3 cities, would benefit the most from this strategy since solar heat gain is the number one concern for the building’s occupants.

Applicable

SHADING OF OVERHEAD SUN In the case of this building, certain parts of the building are protruded outward allowing for shading to take place. Self-shading architecture is of benefit in the climate of Ha Noi since it prevents solar heat gain.

Applicable

Building’s occupants in Da Nang, similarly to Ha Noi, can benefit from this strategy since it prevents solar heat gain.

Applicable

SELF-SHADING ARCHITECTURE Photographic images retrieved via http://www.thelor24ashophouseseries.com/21.htm

122

Ho Chi Minh City would benefit most from this strategy since solar heat gain is a major concern for building’s occupants here.

Applicable

Singapore City - Singapore


HA NOI Refl ective internal surfaces allow natural daylight to be further brought inside the building. In the climate of Ha Noi, where the sky is predominantly overcast, daylight should be taken advantage of. This strategy would be effective here.

Applicable

DA NANG This strategy would also be effective in Da Nang as it takes advantage of natural daylight to reduce electric lighting load within the building.

Applicable

HO CHI MINH CITY With the abundance of daylight in the climate of Ho Chi Minh City, this strategy would be especially effective in reducing eletric lighting load within the building.

THE POOL SHOP HOUSE Singapore City - Singapore

Applicable

REFLECTIVE INTERNAL SURFACES The monolithic lap pool in this building is kept cool and away from solar gain. This pool conductively cools the internal spaces within the building. This strategy may be applied cautiously during the cold period in Ha Noi.

Apply with caution

This strategy would also be effective in Da Nang during the hot period. However, this must be applied cautiously during the short cold period.

Apply with caution

This strategy, if shading successfully used, would be most effective in the climate of Ho Chi Minh City since the temperatures remain consistently hot throughout the year.

Applicable

CONDUCTIVE COOLING VIA SHADED POOL

Photographic images retrieved via http://www.thelor24ashophouseseries.com/21.htm

123


VI. PROOF OF CONCEPT

124


A PROOF OF CONCEPT WAS CREATED AND SIMULATED TO REAFFIRM THE VALIDITY OF THE DESIGN GUIDELINES Preliminary Design Overview

The vegetated roof is integrated into the roof terrace

In order to reaffirm the validity of this study in the context of the three Vietnamese cities, a proof of concept was created. It consisted of two main components: the proposed design & the simulation study. As the three climates share many similarities, it was decided that a design would be conceived using the concepts and the strategies that are feasible in all three climates. After the design was done, a series of simulations were conducted to examine the effectiveness of some strategies whose specifications are derived from the subtle climatic differences amongst the three cities. Due to time constraint, only solar control strategies, or most specifically sun shading devices, were simulated for performance analysis.

Open vertical staircase acts as a corridor and a stack

Open vertical court is dedicated for stack ventilation

Building’s Site Location and Orientation A typical city block in Vietnam often consists of a high concentration of long and narrow building lots. This type of urban layout can be seen below with the three examples extracted from the previous case studies. Additionally, as Vietnam developed over time, its urban landscape saw an amalgamation of the vernacular organic urban layout and Western grid development. With that said, it is hard to pinpoint the most common direction to which urban buildings are oriented. For the proof of concept, a hypothetical building is intended to situate in a typical urban block of Vietnam on the North-to-South axis . It is measured at 4-meter in width and 20-meter in length and is wedged in between two other neighboring buildings, leaving only the facades exposed to the sun.

Open floor plan allows for enhanced cross ventilation Proof of Concept Building’s sectional diagram illustrated by Duy Vo

Proof-of-Concept Building’s Floor Plans

Examples of Typical Urban Block in Vietnam Legend 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

Image 1. 4.5x20 House’s Urban Context

Image 2. Stacking Green’s Urban Context

Image 3. A21 House’s Urban Context

http://www.dezeen.com/2013/05/14/

http://www.dezeen.com/2012/07/09/

http://www.archdaily.com/246049/a21house-a21-studio/

a. Ground Floor

a. Ground Floor

c. Second Floor

Garage Bathroom Storage Room Inner Garden Studio Living Room Kitchen & Dining Bathroom Bedroom Master Bedroom Bathroom Bedroom Roof Terrace Altar Room

d. Roof Terrace

125


SUN SHADING DEVICES WERE SIMULATED TO EXAMINE THEIR IMPACT ON THE BUILDING'S OVERALL ENERGY FOOTPRINT Preliminary Design Overview

Baseline Case

Ha Noi

Da Nang North + South Ho Chi Minh City North + South

Simulated Living Room Floor Area 17.84 m2 Glazing Area

126

Recommended sun shading specifications for the 3 cities

Total Solar Radiation

Case 2

Similar to case 1 except the glazing area is subdivided

Total Energy Consumption

Case 3

“3x9 House” shading device’s specifications used

Energy Use Intensity

Case 4

“Nhabeo House” shading device’s specifications used

Case 1

North + South

11.2 m2

No shading devices installed on the facade of the tested room

Autodesk Ecotect Outputs

The simulation study is conducted only for the double height living room of the proposed building, as it is located nearest to the facade and would most likely be affected by direct solar gain. There is a total of 8 windows, measured at 0.7 m x 2.0 m (27.5 in x 78.7 in). A series of simulation runs are carried out to examine the benefits of the recommended shading devices for each of the three Vietnamese cities. The devices are modeled in Autodesk Ecotect and simulated to measure their impact on (1) the amount of solar radiation entering the interior spaces during the 24-hour period throughout the year (2) annual energy consumption and (3) energy use intensity for two cardinal directions: North & South. Several assumptions were made in order aid the simulation process. They are: • There are four occupants, specifically 2 parents and 2 kids. The activity level is assumed to be of sedentary • Occupants are assumed to wear trouser and shirt indoor (clo = 0.6clo) • Internal humidity level is assumed to be at 80% • The selected comfort zone is set to 18oC - 30.5oC • The building is assumed to have a mixed-mode system with an efficiency of 95%. The operation schedule of this system is set as follow: + Weekdays: On at 20:00 and Off at 6:00 + Weekends: On at 20:00 and Off at 8:00

Diagram of Simulation and Analysis Procedures


SPECIFICATIONS OF SHADING DEVICES USED IN THE SIMULATION FOR HA NOI Simulation Case

Window Size

Glazing Area Used for Calculation

Baseline

0.7 m x 2.0 m

Full Glass

Case 1

0.7 m x 2.0 m

Full Glass

Case 2

0.08 m x 2.0 m 0.35 m x 2.0 m

Subdivided Glass (1/8)

Case 3

0.08 m x 2.0 m

Subdivided Glass (1/8)

Case 4

0.7 m x 0.25 m

Subdivided Glass (1/8)

Overhang Building Orientation North South North South North South North South North South

Vertical Shading Angle (VSA) N/A N/A N/A 65 N/A 65 N/A N/A 45 45

Resulting Depth (m) 0 0 0 0.93 0 0.24 0 0 0.25 0.25

Vertical Fin Horizontal Shading Resulting Depth (m) Angle (VSA) N/A 0 N/A 0 65 0.33 80 0.13 65 0.04 80 0.06 34 0.13 34 0.13 N/A 0 N/A 0

Combined (Y/N) N N N Y N Y N N N N

SPECIFICATIONS OF SHADING DEVICES USED IN THE SIMULATION FOR da NANG Simulation Case

Window Size

Glazing Area Used for Calculation

Baseline

0.7 m x 2.0 m

Full Glass

Case 1

0.7 m x 2.0 m

Full Glass

Case 2

0.35 m x 0.5 m

Subdivided Glass (1/8)

Case 3

0.08 m x 2.0 m

Subdivided Glass (1/8)

Case 4

0.7 m x 0.25 m

Subdivided Glass (1/8)

Overhang Building Orientation North South North South North South North South North South

Vertical Shading Angle (VSA) N/A N/A 82 60 82 60 N/A N/A 45 45

Resulting Depth (m) 0 0 0.07 1.16 0.07 0.29 0 0 0.25 0.25

Vertical Fin Horizontal Shading Resulting Depth (m) Angle (VSA) N/A 0 N/A 0 65 0.33 75 0.19 65 0.16 75 0.09 34 0.13 34 0.13 N/A 0 N/A 0

Combined (Y/N) N N Y Y Y Y N N N N

SPECIFICATIONS OF SHADING DEVICES USED IN THE SIMULATION FOR Ho chi minh city Simulation Case

Window Size

Glazing Area Used for Calculation

Baseline

0.7 m x 2.0 m

Full Glass

Case 1

0.7 m x 2.0 m

Full Glass

Case 2

0.35 m x 0.5 m

Subdivided Glass (1/8)

Case 3

0.08 m x 2.0 m

Subdivided Glass (1/8)

Case 4

0.7 m x 0.25 m

Subdivided Glass (1/8)

Overhang Building Orientation North South North South North South North South North South

Vertical Shading Angle (VSA) N/A N/A 60 50 60 50 N/A N/A 45 45

Resulting Depth (m) 0 0 1.16 1.68 0.29 0.42 0 0 0.25 0.25

Vertical Fin Horizontal Shading Resulting Depth (m) Angle (VSA) N/A 0 N/A 0 65 0.33 50 0.59 65 0.16 50 0.3 34 0.13 34 0.13 N/A 0 N/A 0

Combined (Y/N) N N Y Y Y Y N N N N

127


the TOTAL SOLAR RADIATION a BUILDING IN ha noi IS EXPOSED TO WHEN FACING NORTH IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 151.9

EUI 151.6

Baseline Case - No Shade

Case 1: Full Glass

EUI 151.1

Case 2: Subdivided Glass

EUI 151.1

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -19%

288000

Case 2 vs. Baseline -10%

288000

Case 3 vs. Baseline -36%

288000

Case 4 vs. Baseline -37%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 64.302 kWh

128

EUI 151.8

Total Solar Radiation 51.786 kWh

Total Solar Radiation 57.799 kWh

Total Solar Radiation 40.895 kWh

Total Solar Radiation 40.233 kWh


the TOTAL SOLAR RADIATION a BUILDING IN ha noi IS EXPOSED TO WHEN FACING SOUTH IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 146.7

EUI 146.3

Baseline Case - No Shade

EUI 146.3

Case 1: Full Glass

EUI 146.2

Case 2: Subdivided Glass

EUI 146.1

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -17%

288000

Case 2 vs. Baseline -18%

288000

Case 3 vs. Baseline -25%

288000

Case 4 vs. Baseline -25%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 95.174 kWh

Total Solar Radiation 78.585 kWh

Total Solar Radiation 78.262 kWh

Total Solar Radiation 71.757 kWh

Total Solar Radiation 71.106 kWh

129


the TOTAL SOLAR RADIATION a BUILDING IN DA NANG IS EXPOSED TO WHEN FACING NORTH IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 5.5

EUI 5.2

Baseline Case - No Shade

Case 1: Full Glass

EUI 5.1

Case 2: Subdivided Glass

EUI 5.1

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -26%

288000

Case 2 vs. Baseline -21%

288000

Case 3 vs. Baseline -35%

288000

Case 4 vs. Baseline -34%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 73.245 kWh

130

EUI 5.3

Total Solar Radiation 54.168 kWh

Total Solar Radiation 57.985 kWh

Total Solar Radiation 47.582 kWh

Total Solar Radiation 48.276 kWh


the TOTAL SOLAR RADIATION a BUILDING IN DA NANG IS EXPOSED TO WHEN FACING SOUTH IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 5.5

EUI 5.2

Baseline Case - No Shade

EUI 5.2

Case 1: Full Glass

EUI 5.2

Case 2: Subdivided Glass

EUI 5.1

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -24%

288000

Case 2 vs. Baseline -25%

288000

Case 3 vs. Baseline -28%

288000

Case 4 vs. Baseline -29%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 87.912 kWh

Total Solar Radiation 66.921 kWh

Total Solar Radiation 65.886 kWh

Total Solar Radiation 62.246 kWh

Total Solar Radiation 62.246 kWh

131


the TOTAL SOLAR RADIATION a BUILDING IN ho chi minh city IS EXPOSED TO WHEN FACING north IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 25.2

EUI 25.0

Baseline Case - No Shade

Case 1: Full Glass

EUI 25.0

Case 2: Subdivided Glass

EUI 24.9

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -32%

288000

Case 2 vs. Baseline -33%

288000

Case 3 vs. Baseline -34%

288000

Case 4 vs. Baseline -35%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 79.515 kWh

132

EUI 25.0

Total Solar Radiation 53.830 kWh

Total Solar Radiation 53.253 kWh

Total Solar Radiation 52.123 kWh

Total Solar Radiation 51.360 kWh


the TOTAL SOLAR RADIATION a BUILDING IN ho chi minh city IS EXPOSED TO WHEN FACING SOUTH IS PARAMETRICALLY SIMULATED AND ANALYZED

EUI 25.1

EUI 24.9

Baseline Case - No Shade

EUI 24.9

Case 1: Full Glass

EUI 24.9

Case 2: Subdivided Glass

EUI 24.9

Case 3: 3x9 House Shade

Case 4: Nhabeo House Shade

Wh

Wh

Wh

Wh

Wh

320000+

320000+

320000+

320000+

320000+

288000

Case 1 vs. Baseline -31%

288000

Case 2 vs. Baseline -33%

288000

Case 3 vs. Baseline -33%

288000

Case 4 vs. Baseline -34%

288000

256000

256000

256000

256000

256000

224000

224000

224000

224000

224000

1 92000

1 92000

1 92000

1 92000

1 92000

1 60000

1 60000

1 60000

1 60000

1 60000

1 28000

1 28000

1 28000

1 28000

1 28000

96000

96000

96000

96000

96000

64000

64000

64000

64000

64000

32000

32000

32000

32000

32000

0

0

0

0

0

Total Solar Radiation 103.693 kWh

Total Solar Radiation 71.156 kWh

Total Solar Radiation 69.443 kWh

Total Solar Radiation 69.443 kWh

Total Solar Radiation 68.307 kWh

133


30 SIMULATION RUNS WERE CONDUCTED AND ANALYZED TO MEASURE SUN SHADING DEVICES'S IMPACT ON BUILDING'S OVERALL energy consumption and Energy use intensity ENERGY CONSUMPTION IN HA NOI RESOURCE USAGE - Energy Consumption Orientation: North Heating (kWh) Cooling (kWh) Baseline 2470.8 239.3 Case 1 2476.0 228.5 vs.Baseline +0.2% -4.5% Case 2 2473.6 233.7 vs. Baseline +0.1% -2.3% Case 3 2477.0 219.3 vs. Baseline +0.3% -8.4% Case 4 2477.4 218.7 vs. Baseline +0.3% -8.6% Orientation: South Heating (kWh) Cooling (kWh) Baseline 2388.2 228.7 Case 1 2395.8 214.4 vs.Baseline +0.3% -6.2% Case 2 2395.9 214.2 vs. Baseline +0.3% -6.3% Case 3 2398.9 208.6 vs. Baseline +0.4% -8.8% Case 4 2399.2 208.0 vs. Baseline +0.5% -9.0%

134

ENERGY CONSUMPTION IN DA NANG RESOURCE USAGE - Energy Consumption Orientation: North Heating (kWh) Cooling (kWh) Baseline 0 97.814 Case 1 0 93.014 vs.Baseline N/A -4.9% Case 2 0 93.982 vs. Baseline N/A -3.9% Case 3 0 91.573 vs. Baseline N/A -6.4% Case 4 0 91.389 vs. Baseline N/A -6.6% Orientation: South Heating (kWh) Cooling (kWh) Baseline 4.908 93.302 Case 1 4.932 88.038 vs.Baseline +0.5 -5.6% Case 2 4.932 87.8 vs. Baseline +0.5 -5.9% Case 3 4.944 87.061 vs. Baseline +0.7 -6.7% Case 4 4.944 86.871 vs. Baseline +0.7 -6.9%

The simulation indicates the importance of sun shading devices as they help significantly reducing the amount of solar radiation the building is exposed to on the North & South in Ha Noi. From the results for both solar radiation and energy consumption, specifically cooling, case 4 is the most effective sun shading device. Case 1 performs least effectively in terms of reducing the amount of solar radiation enteringthe building. However it is important to note that the recommended specifications are suggested to only shade the building during the period where temperature conditions rise above 28oC (See Appendix A). However, as Ha Noi experiences period where the temperature conditions drop below comfort zone, case 4 seems to backlash. It is not able to take advantage of passive solar gain during this particular period.

The simulation indicates the importance of sun shading devices in reducing the amount of solar radiation the building is exposed to on the North & South in Da Nang. Similarly to Ha Noi, case 4 is the most effective sun shading device in Da Nang as it reduces the most amount of solar radiation and accounts for the largest energy cooling out of the 4 alternative cases (6.6% for North and 6.9% for South) . Case 1 and case 2 do not perform as effectively. However, as Da Nang experiences a short period where the temperature conditions drop below comfort zone, case 4 seems to backlash, especially on the South. It is not able to take advantage of passive solar gain during this particular period.

Ha noi

DA NANG

ENERGY CONSUMPTION IN HO CHI MINH CITY RESOURCE USAGE - Energy Consumption Orientation: North Heating (kWh) Cooling (kWh) Baseline 0 448.879 Case 1 0 445.353 vs.Baseline N/A -0.8% Case 2 0 445.549 vs. Baseline N/A -0.7% Case 3 0 445.306 vs. Baseline N/A -0.8% Case 4 0 445.075 vs. Baseline N/A -0.8% Orientation: South Heating (kWh) Cooling (kWh) Baseline 0 448.594 Case 1 0 443.911 vs.Baseline N/A -1.0% Case 2 0 443.993 vs. Baseline N/A -1.0% Case 3 0 445.021 vs. Baseline N/A -0.8% Case 4 0 444.789 vs. Baseline N/A -0.8%

Similarly to the previous two cities, sun shading devices prove to be valuable as they are able to significantly reduce the amount of solar radiation entering the interior of buildings.They are also somewhat effective in terms of reducing the overall energy footprint of the buildings. Unlike the previous two cities, case 3 and case 4, though still having the most significant reduction in solar radiation, are not more effective than case 1 and case 2. It is important to note here that the specifications used for case 1 and case 2 are already more than adequate to shade the building during all the hours where the temperature conditions rise above 28oC (See Appendix C)

HO CHI MINH CITY


VII. CONCLUSION

In conclusion, it is important for designers to understand all of the climatic

• Take advantage of prevailing winds, natural daylight, and potentially diurnal

forces present on the building site so that they can arrive to a climatically

swing to cut down on the amount of energy consumed for mechanical cooling

responsive, and ultimately energy effiicient final design. This study qualitatively

and electric lighting.

provides a comprehensive set of design guidelines for building low energy and

• During the period when temperatures drop below comfort zone, devise

climatically responsive urban in-fill homes in three specific sub climate zones :

strategies to prevent contact with low temperatures & prevailing winds.

Humid subtropical with distinct dry winter (Cwa), Tropical Monsoon (Am) and

• Encourage occupants to proactively adapt their thermal comfort according

Tropical Wet and Dry (Aw).

to their surrounding environment via choice of clothing and activities.

For locations that fall inside the “Humid Subtropical

For locations that fall inside the “Tropical Wet & Dry”

with distinct dry winter” climate, designers should:

climate, designers should:

• Block moisture, high temperatures, and intense sun to avoid causing thermal

• Block high temperatures, and intense sun to avoid causing thermal discomfort

discomfort for the building’s occupants.

for the building’s occupants. During the rainy season, block moisture.

• Take advantage of prevailing winds, natural daylight to cut down on energy

• Take advantage of prevailing winds, natural daylight, diurnal swing to cut

consumed for mechanical cooling and electric lighting.

down on energy consumed for mechanical cooling and electric lighting.

• During the period when temperatures drop below comfort zone, devise

• During the period when the humidity levels drop significantly, employ

strategies to prevent contact with low temperatures & prevailing winds.

evaporative cooling strategies to cool and add moisture to the internal spaces.

• Encourage occupants to proactively adapt their thermal comfort according

• Encourage occupants to proactively adapt their thermal comfort according

to their surrounding environment via choice of clothing and activities.

to their surrounding environment via choice of clothing and activities.

For locations that fall inside the “Tropical Monsoon” climate, designers should: • Block moisture, high temperatures, and intense sun when it is to hot for

135


VIII. FUTURE WORKS

Due to time constraint, this study did not take into account factors such

as urban density and development when developing the design guidelines. It is my hope that future studies can tackle these aspects as they play important roles in determining the feasibility and measuring the overall effectiveness of the recommended strategies in an urban context. Additionally, it would be of benefit to explore active mechanical means to further push energy conservation as well as to be better combined with passive, climate responsive design approach.

136


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2183. To, K. (2008). “Tube House” and “Neo Tube House” in Hanoi: A Comparative Study on Identity

2013, from http://web.worldbank.org/WBSITE/EXTERNAL/COUNTRIES/EASTASIAPACIFICEXT/

and Typology. Journal of Asian Architecture and Building Engineering (JAABE) , 7 (2).

EXTEAPREGTOPRURDEV/0,,contentMDK:20534368~menuPK:3127821~pagePK:340041

To, K. (2008). Tube Houses in Hanoi’s Old Quarter. Kumamoto: Kumamoto University.

73~piPK:34003707~theSitePK:573964,00.html

Todesco, G. (1996). Super-efficient buildings: how low can you go? ASHRAE Journal (38(12)), 35-40.

World Meteorological Organization. (n.d.). Retrieved February 24, 2013, from World Weather Information Service: www.worldweather.org/082/c00309.htm

Tran Hung, D. U. (2006). Assessment with satellite data of the urban heat island effects in Asian

Yasmin Bhattacharya, M. M. (2009). conditions, Psychrometric Chart Tutorial: A tool for

mega cities. International Journal of Applied Earth Observation and Geoinformation , 8 (1), 34-

understanding human thermal comfort. American Solar energy Society Conference. Buffalo, New

48.

York.

Troy Kimmel, J. (2006). Koppen Climate Classification Flow Chart. Retrieved March 12, 2013,

Yeang, K. (2001). The Green Agenda. In B. Stagno, Tropical Architecture: Critical regionalism in the

from GRG301K - Weather and Climate: http://www.utexas.edu/depts/grg/kimmel/GRG301K/

Age of Globalization (pp. 215-228). London: John Wiley & Sons.

grg301kkoppen.html United States Department of Agriculture. (n.d.). Natural Resources Conservation Service. Retrieved 06 23, 2013, from http://www.wcc.nrcs.usda.gov/climate/windrose.html Vietnam Electricity. (n.d.). GIZ Renewable Energy Project. Retrieved February 23, 2013, from GIZ Renewable Energy Project: http://www.renewableenergy.org.vn Waibel, M. (2009). 1st report on the awareness, acceptance and needs of energy efficient structures and goods among middle and upper-class households of Ho Chi Minh city. Survey report for the Megacity Research Project, Ho Chi Minh Vietnam . Waibel, R. E. (2009). Climate Change and Challenges for the Urban Development of Ho Chi Minh City/Vietnam. Pacific News (31). WeatherBase: Historical Weather . (2012). Retrieved February 24, 2013, from WeatherBase:

140

World Bank. (2009). Rural Development and Agriculture in Vietnam. Retrieved February 24,

http://www.weatherbase.com/weather/


X. APPENDICES

141


Appendix A Shading Mask Analysis: Ha Noi

142


RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST N

345°

300°

60°

1st Jun 1st May 285°

75°

1st Apr 1st Oct 1st Mar

1st Nov 105°

255° 1st Feb 15

14

13

12

11

10

9

8

7

240°

1st Dec 120°

The top priority in Ha Noi is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Northern orientation prior to June 21st, a combination of a shallow overhang and a pair of vertical fins would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 2 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

210°

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Sep

1st Apr

1st Oct 1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

210°

150° 195°

N

345°

180°

165°

NORTHERN ORIENTATION COMBINED SHADING MASK

15°

330°

30°

315°

45°

300°

60° 1st Jul 1st Aug

285°

75°

1st Sep 1st Oct 1st Mar

1st Nov 105°

255° 1st Feb 15

16

150° 195°

165°

180°

NORTHERN ORIENTATION OF HA NOI, VIETNAM

17

45°

135°

225°

1st Jan

30°

315°

45°

16

330°

30°

315°

17

15°

15°

330°

1st Jan

N

345°

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

Similarly to the period prior to June 21st in Ha Noi, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Northern orientation, a combination of a shallow overhang and a pair of vertical fins would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Single Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 2 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

After identifying the 2 shading devices most effective for the building during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. The specifications of the shading devices are as follow: • Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 2

135°

210°

150° 195°

180°

165°

RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

Ha Noi - VIETNAM

143


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST N

345°

N

345°

15° 30°

330°

15°

330°

45°

315°

30°

315°

45°

60°

300° 1st Jun

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Sep

1st Apr

1st Mar 255° 1st Feb

105°

1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

120°

225°

135°

210°

The top priority is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation prior to June 21st, a cshallow overhang would be adequate enough to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 83o Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

165°

180°

345°

45°

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Sep

1st Apr

1st Oct 1st Nov 105°

255°

15

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

210°

1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

15

16

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

150° 180°

165°

SOUTHERN ORIENTATION COMBINED SHADING MASK

Similarly to the period prior to June 21st, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 65o • Vertical Fin + Horizontal Shading Angle (HSA) = 80o Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

After identifying the 2 shading devices most effective for the building during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 65o • Vertical Fin + Horizontal Shading Angle (HSA) = 80o + Number: 1

150° 195°

180°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

144

1st Oct

30°

315°

16

1st Sep

1st Apr

15°

330°

17

75°

195°

SOUTHERN ORIENTATION OF HA NOI, VIETNAM N

1st Aug

210°

150° 195°

1st Jul

1st May 285°

Ha Noi - VIETNAM


345°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST 345°

45°

30°

45°

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Apr

1st Sep

270°

90° 1st Oct

1st Mar

1st Nov 105°

255° 1st Feb 15

16

30°

315°

315°

17

330°

15°

330°

1st Jan

15°

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Western orientation prior to June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Apr

1st Sep

270°

90° 1st Oct

1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

15

16

14

13

12

11

10

150° 195°

345°

120°

225°

135°

150° 195°

165°

WESTERN ORIENTATION COMBINED SHADING MASK

15°

330°

30°

45°

315°

300°

60°

1st Jul

1st Jul

1st Aug

1st Aug

285°

75°

1st Sep 1st Sep 90° 1st Oct

270° 1st Oct

1st Nov 105°

1st Nov 255° 1st Dec 15

16

1st Dec

7

165°

WESTERN ORIENTATION OF HA NOI, VIETNAM

17

8

240°

210° 210°

9

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

210°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Western orientation after June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

As previously mentioned, it is best to avoid this particular orientation in Ha Noi due to high temperature conditions. However, if it cannot be avoided, it is best to use devices such as roller shade, bamboo screen or window shutters to allow for natural daylighting while effectively protect the interior from unwanted solar heat gain.

150° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

HA NOI - VIETNAM

145


315°

45°

60°

300° 1st Jun

1st Jun

1st May 285°

1st May 75°

1st Apr

1st Apr 90°

270°

1st Mar

1st Mar

105° 1st Feb

255° 1st Feb 17

15

16

45°

315° 30°

330°

1st Jan

30°

330°

15°

345°

15°

345°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST

14

13

12

11

10

9

8

7

1st Jan 120°

240°

135°

225°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern orientation prior to June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

60°

300° 1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Apr

1st Sep

270°

90° 1st Oct

1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

15

16

14

13

12

11

10

195°

345°

135°

225°

150° 165°

EASTERN ORIENTATION COMBINED SHADING MASK

15°

330°

30°

315°

45°

300°

60°

1st Jun

1st Jul 1st Aug

1st May 285°

75°

1st Apr

1st Sep

270°

90° 1st Oct

1st Mar

1st Nov 105°

255° 1st Feb 15

14

13

12

11

10

9

8

7

240°

1st Dec 120°

225°

135°

210°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern orientation after June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

As previously mentioned, it is best to avoid this particular orientation in Ha Noi due to high temperature conditions. However, if it cannot be avoided, it is best to use devices such as roller shade, bamboo screen or window shutters to allow for natural daylighting while effectively protect the interior from unwanted solar heat gain.

150° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

146

1st Dec 120°

195°

165°

EASTERN ORIENTATION OF HA NOI, VIETNAM

16

7

240°

210°

17

8

150°

210°

1st Jan

9

HA NOI - VIETNAM


Appendix B Shading Mask Analysis: Da Nang

147


RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST

N

345°

15°

330° N

345°

15°

330°

315°

30°

315°

The top priority is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur.

45°

300°

60°

1st Jun 1st May 285°

75°

In the case of the Northern orientation prior to June 21st, a combination of a shallow overhang and a pair of vertical fins would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang

1st Apr

1st Mar 255° 1st Feb 1st Jan

105° 17

15

16

14

13

12

11

10

9

8

7

240°

120°

225°

135°

210°

+ Vertical Shading Angle(VSA) = 83o • Vertical Fin + Horizontal Shading Angle (HSA) = 67.5o + Number: 2 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

NORTHERN ORIENTATION OF DA nANG, VIETNAM N

345°

30°

315°

45°

300°

60° 1st Jul 1st Aug

285°

75° 1st Sep

1st Oct 1st Mar 1st Nov 105°

255° 1st Feb 17

15

16

14

13

12

11

10

9

8

1st Dec

7

240°

120°

225°

135°

210°

1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 1st Oct 1st Mar 1st Nov 105°

255° 1st Feb 17

1st Jan

16

15

14

13

12

11

10

9

180°

8

1st Dec

7

240°

120°

225°

135°

150° 180°

165°

NORTHERN ORIENTATION COMBINED SHADING MASK

Similarly to the period prior to June 21st, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the

After identifying the 2 shading devices most effective for the

case of the Northern orientation, a combination of a shallow overhang and a pair of vertical fins would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices

building during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year.

are as follow:

The specifications of the shading devices are as follow:

• Overhang + Vertical Shading Angle(VSA) = 82o • Single Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 2

• Overhang + Vertical Shading Angle(VSA) = 82o • Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 2

Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

150° 195°

165°

RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

148

60°

15°

330°

1st Jan

300°

195°

165°

180°

45°

210°

150° 195°

30°

DA NANG - VIETNAM


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST N

345°

N

345°

15° 30°

330°

15°

330°

30°

315° 315°

45°

300°

60°

1st Jun 1st May 285°

75°

1st Apr

1st Mar 255° 1st Feb 1st Jan

105° 17

15

16

14

13

12

11

10

9

8

7

240°

120°

225°

135°

210°

150° 195°

The top priority is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation prior to June 21st, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 60o • Vertical Fin + Horizontal Shading Angle (HSA) = 75o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

300°

60° 1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 1st Oct 1st Mar 1st Nov 105°

255° 1st Feb 17

1st Jan

16

15

14

SOUTHERN ORIENTATION OF DA nANG, VIETNAM N

10

9

8

1st Dec

7

120°

225°

135°

150° 180°

165°

SOUTHERN ORIENTATION COMBINED SHADING MASK

30°

315°

45°

300°

60° 1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 1st Oct 1st Nov 105°

255° 15

16

11

15°

330°

17

12

240°

195°

345°

13

210°

165°

180°

45°

14

13

12

11

10

9

8

1st Dec

7

240°

120°

225°

135°

210°

150° 195°

180°

Similarly to the period prior to June 21st, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 80o • Single Vertical Fin + Horizontal Shading Angle (HSA) = 82.5o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

After identifying the 2 shading devices most effective for the building during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 60o • Vertical Fin + Horizontal Shading Angle (HSA) = 75o + Number: 1

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

DA NANG - VIETNAM

149


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST 345° 345°

15°

330°

15°

30°

30°

330°

315°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur.

45°

315°

60°

300° 1st Jun 1st May 285°

75°

In the case of the Western orientation prior to June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word,

1st Apr 90°

270° 1st Mar

105°

255° 1st Feb 16

17

1st Jan

14

15

13

12

11

10

9

8

7 120°

240°

135°

225°

210°

this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

45°

300°

60° 1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 270°

90° 1st Oct

1st Mar 1st Nov 105°

255° 1st Feb 1st Jan

17

16

15

14

9

8

1st Dec

7

120°

135°

210°

165°

345°

150° 165°

WESTERN ORIENTATION COMBINED SHADING MASK

15° 30°

330°

45°

315°

60°

300° 1st Jul

1st Jul 1st Aug

1st Aug

75°

285° 1st Sep

1st Sep

90° 1st Oct

270° 1st Oct

1st Nov 105°

1st Nov 255° 15

14

13

12

11

10

9

8

1st Dec

7

120°

240°

135°

225°

210°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Western orientation after June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices

As previously mentioned, it is best to avoid this particular orientation in Da Nang due to high temperature conditions. However, if it cannot be avoided, it is best to use devices such as roller shade, bamboo screen or window shutters to allow for natural daylighting while effectively protect the interior from unwanted solar heat gain.

such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

150° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

150

10

225°

WESTERN ORIENTATION OF DA nANG, VIETNAM

17

11

240°

195°

16

12

150° 195°

1st Dec

13

DA NANG - VIETNAM


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST 345° 345°

15°

330°

315°

300°

60°

1st Jun

1st Jun

1st May 285°

1st May 75°

1st Apr

1st Apr 270°

90° 1st Mar

1st Mar 255° 1st Feb 1st Jan

105° 1st Feb 17

15

14

13

12

11

10

9

8

1st Jan

7

240°

120°

225°

135°

210°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern orientation prior to June 21st, a deep overhang would be able to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 20o Note: When the overhang is too deep, it traps hot air and creates a dark zone underneath. In order to avoid these two things from occuring, designers should use dynamic overhang solution or slanted horizontal louvers.

60°

300°

1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 90° 1st Oct

270° 1st Mar

1st Nov 105°

255° 1st Feb 1st Jan

17

16

15

14

13

12

11

10

9

8

165°

1st Dec

7

120°

240°

225°

150° 195°

45°

315°

45°

16

30°

330°

30°

135°

150°

210° 195°

EASTERN ORIENTATION OF DA nANG, VIETNAM 345°

15°

330°

30°

315°

45°

300°

60° 1st Jul

1st Jun

1st Aug

1st May 285°

75° 1st Sep

1st Apr 270°

90° 1st Oct

1st Mar 1st Nov 105°

255° 1st Feb 1st Jan

17

EASTERN ORIENTATION COMBINED SHADING MASK

15

16

14

13

12

11

10

9

8

1st Dec

7

240°

120°

225°

135°

Similarly to the period after June 21st , the top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern orientation, a deep overhang would be able to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 10o Note: When the overhang is too deep, it traps hot air and creates a dark zone underneath. In order to avoid these two things from occuring, designers should use dynamic overhang solution or slanted horizontal louvers.

After identifying the 2 shading devices most effective for the building during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. Based on the combined shading mask, the most appropriate shading device for this orientation would be a retractable overhang, whose maximum depth is derived from the VSA of 10o The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 10o

150°

210° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

DA NANG - VIETNAM

151


Appendix C Shading Mask Analysis: Ho Chi Minh City

152


RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST

N

345°

15° 30°

330° N

345°

15°

45°

315°

60°

300° 1st Jun

75°

285° 1st May 1st Apr

1st Mar 255°

105°

1st Feb 1st Jan

17

16

15

14

13

12

11

10

9

8

7

240°

120°

135°

225°

210°

The top priority is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Northern orientation prior to June 21st, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 60o • Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

NORTHERN ORIENTATION OF HO CHI MINH CITY, VIETNAM N

345°

30°

315°

45°

300°

60° 1st Jul

285°

75° 1st Aug 1st Sep

1st Oct 255°

105° 17

14

13

12

285° 1st May

75° 1st Aug

1st Apr

1st Sep

1st Mar

1st Oct

255° 1st Feb

105° 17

1st Jan

15

16

14

13

12

11

10

9

8

1st Nov

7

1st Dec 120°

240°

225°

135°

150° 180°

165°

NORTHERN ORIENTATION COMBINED SHADING MASK

15°

330°

15

1st Jul

1st Jun

195°

165°

180°

60°

300°

210°

150° 195°

16

45°

315° 30°

330°

11

10

9

8

1st Nov

7

1st Dec 120°

240°

225°

135°

Similarly to the period prior to June 21st, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Northern orientation, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 60o • Single Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

After identifying the 2 shading devices most effective for the building in Ho Chi Minh City during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 60o • Vertical Fin + Horizontal Shading Angle (HSA) = 65o + Number: 1

150°

210° 195°

180°

165°

RECOMMENDED SHADING MASK FOR NORTHERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

HO CHI MINH CITY - VIETNAM

153


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST N

345°

45°

60°

1st Jun 75°

285° 1st May 1st Apr

1st Oct

1st Nov 105°

255° 15

12

13

14

11

10

9

8

1st Dec

7

240°

120°

225°

135°

210°

The top priority is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation prior to June 21st, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 50o • Vertical Fin + Horizontal Shading Angle (HSA) = 50o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

150° 195°

180°

N

345°

285° 1st May

75° 1st Aug

1st Apr

1st Sep

1st Mar

1st Oct 105°

255° 1st Feb 17

1st Jan

15

16

14

13

12

11

10

9

8

1st Nov

7

1st Dec 120°

240°

135°

225°

150°

210° 195°

180°

165°

SOUTHERN SHADINGMASK MASK SOUTHERNORIENTATION ORIENTATION COMBINED COMBINED SHADING

30°

45°

315°

60°

300°

1st Jul 75° 1st Aug

285°

1st Sep 1st Mar 1st Feb 255°

105° 15

14

13

12

11

10

9

8

7 120°

240°

225°

135°

210°

150° 195°

180°

Similarly to the period prior to June 21st, the top priority for the period after June 21st is to shade the building facades during the hours when temperatures within the range of 27oC and 38oC occur. In the case of the Southern orientation, a combination of a shallow overhang and a single vertical fin would be adequate to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 50o • Single Vertical Fin + Horizontal Shading Angle (HSA) = 50o + Number: 1 Note: If daylight and air movement are desired throughout the day, dynamic permeable shading devices can be used.

After identifying the 2 shading devices most effective for the building in Ho Chi Minh City during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 50o • Vertical Fin + Horizontal Shading Angle (HSA) = 50o + Number: 1

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

154

1st Jul

1st Jun

15°

330°

16

60°

300°

165°

SOUTHERN ORIENTATION OF HO CHI MINH CITY, VIETNAM

17

45°

315°

300°

1st Jan

30°

30°

315°

16

15°

330°

15°

330°

17

N

345°

HO CHI MINH CITY - VIETNAM


RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST

45°

315°

60°

300° 1st Jun

75°

285° 1st May 1st Apr

90°

270° 1st Mar

105°

255°

1st Jan

17

16

45°

315° 30°

330°

1st Feb

30°

330°

15°

345°

15°

345°

15

14

13

12

11

10

9

8

7 120°

240°

135°

225°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Western orientation prior to June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

60°

300°

1st Jul

1st Jun 285° 1st May

75° 1st Aug

1st Apr

1st Sep

270°

90°

1st Mar

1st Oct 105°

255° 1st Feb 17

1st Jan

15

16

14

13

12

11

10

1st Dec 120°

135°

225°

150° 195°

WESTERN ORIENTATION OF HO CHI MINH CITY, VIETNAM

WESTERN ORIENTATION COMBINED SHADING MASK

30°

330°

45°

315°

60°

300°

1st Jul

1st Jul 1st Aug 285°

75° 1st Aug

1st Sep 1st Sep 90°

270° 1st Oct

1st Oct 1st Nov 255°

105° 17

165°

15°

345°

16

7

165°

195°

1st Dec

8

1st Nov

240°

210° 150°

210°

9

15

14

13

12

11

10

9

8

1st Nov

7

1st Dec 120°

240°

135°

225°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Western orientation after June 21st, due to the high frequency of temperature within the range of 27oC and 38oC, the shading mask suggests the VSA to be 0o, which implies that there should not be any opening placed in this orientation or in another word, this orientation should be avoided completely. However, in the case, where the building owners have no control over the building’s orientation, which is often the case in urban area of Vietnam, devices such as roller shade, bamboo lattice screen, window shutters would be effective. These devices are not only able to completely shade the openings yet permeable to let daylight enter the room.

As previously mentioned, it is best to avoid this particular orientation in Ho Chi Minh City due to high temperature conditions. However, if it cannot be avoided, it is best to use devices such as roller shade, bamboo screen or window shutters to allow for natural daylighting while effectively protect the interior from unwanted solar heat gain.

150°

210° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

HO CHI MINH CITY - VIETNAM

155


345°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD PRIOR TO JUNE 21ST 345°

315°

45°

300°

60° 1st Jun

1st Jun 285°

75° 1st May

1st May

1st Apr

1st Apr 270°

90°

1st Mar

1st Mar

255°

1st Jan

16

30°

45°

30°

315°

17

330°

15°

330°

1st Feb

15°

15

14

13

12

11

10

9

8

105° 1st Feb 7

1st Jan

240°

120°

225°

135°

The top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern orientation prior to June 21st, a deep overhang would be able to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 15o Note: When the overhang is too deep, it traps hot air and creates a dark zone underneath. In order to avoid these two things from occuring, designers should use dynamic overhang solution or slanted horizontal louvers.

300°

60° 1st Jul

1st Jun 285° 1st May

75° 1st Aug

1st Apr

1st Sep

270°

90°

1st Mar

1st Oct

255° 1st Feb

105° 17

1st Jan

15

16

14

13

11

10

150° 195°

345°

1st Dec 120°

225°

135°

150° 195°

165°

EASTERN ORIENTATION COMBINED SHADING MASK

30°

315°

45°

300°

Similarly to the period after June 21st , the top priority is to shade the building facades during the hours where temperatures within the range of 27oC and 38oC occur. In the case of the Eastern

60° 1st Jul

285°

75° 1st Aug 1st Sep

270°

90° 1st Oct

255°

105° 15

14

13

12

11

10

9

8

1st Nov

7

1st Dec 120°

240°

225°

135°

210°

orientation, a deep overhang would be able to shade the building’s facade during the hot hours. The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 33o Note: When the overhang is too deep, it traps hot air and creates a dark zone underneath. In order to avoid these two things from occuring, designers should use dynamic overhang solution or slanted horizontal louvers.

After identifying the 2 shading devices most effective for the building in Ho Chi Minh City during 2 specific periods of the year, a combined shading mask is determined for the best device that can successfully shade the building all year. Based on the combined shading mask, the most appropriate shading device for this orientation would be a retractable overhang, whose maximum depth is derived from the VSA of 10o The specifications of the shading devices are as follow: • Overhang + Vertical Shading Angle(VSA) = 15o

150° 195°

165°

RECOMMENDED SHADING MASK FOR WESTERN ORIENTATION DURING THE PERIOD AFTER JUNE 21ST

156

7

15°

330°

16

1st Nov

165°

EASTERN ORIENTATION OF HO CHI MINH CITY, VIETNAM

17

8

240°

210° 210°

9

HO CHI MINH CITY - VIETNAM

Profile for Duy Vo

MSSD Synthesis Project 2012 - 2013  

This study aims to combine passive design approach and energy conservation into a hybrid set of strategies for designing low energy climate...

MSSD Synthesis Project 2012 - 2013  

This study aims to combine passive design approach and energy conservation into a hybrid set of strategies for designing low energy climate...

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