Thermal comfort through envelope design by Yamini Gupta

DISSERTATION Year: 2020-21 Batch No. 18

THERMAL COMFORT THROUGH ENVELOPE DESIGN

Undertaken by: Yamini Gupta Enrollment No.: 16E1AAARF40P139 V Year B.Arch (C)

Prof. N.S. Rathore

Prof. ARCHANA SINGH

GUIDE

COORDINATOR

Aayojan School of Architecture ISI-4, RIICO Institutional Block, Sitapura, Jaipur-302022

APPROVAL The study titled â&#x20AC;&#x2022;Thermal comfort through envelope design.â&#x20AC;? is hereby approved as an original work of Yamini Gupta, enrollment no. 16E1AAARF40P139 on the approved subject carried out and presented in manner satisfactory to warrant its acceptance as per the standard laid down by the university. This report has been submitted in the partial fulfillment for the award of Bachelor of Architecture degree from Rajasthan Technical University, Kota. It is to be understood that the undersigned does not necessarily endorse or approve any statement made, any opinion expressed or conclusion drawn therein, but approves the study only for the purpose it has been submitted. December 2020 Jaipur

Prof. K.S. MAHAJANI EXTERNAL EXAMINER 1

PRINCIPAL

Prof. ARCHANA SINGH EXTERNAL EXAMINER 2

COORDINATOR

DECLARATION I, Yamini Gupta, here by solemnly declare that the research work undertaken by me, titled ‘ Thermal comfort through envelope design. ’ is my original work and wherever I have incorporated any information in the form of photographs, text, data, maps, drawings, etc. from different sources, has been duly acknowledged in my report. This dissertation has been completed under the supervision of the guide allotted to me by the school. Further, whenever and wherever my work shall be presented or published it will be jointly authored with my guide. Yamini Gupta V Year B.Arch (C) Aayojan School of Architecture, Jaipur

CERTIFICATE This is to certify that the research titled, ‗ Thermal comfort through envelope design’, is a bonafide work by Yamini Gupta of Aayojan School of Architecture, Jaipur. This research work has been completed under my guidance and supervision in a satisfactory manner. This report has been submitted in partial fulfillment of award of BACHELOR OF ARCHITECTURE degree from Rajasthan Technical University, Kota. This research work fulfills the requirements relating to the nature and standard laid down by the Rajasthan Technical University. Prof. N.S.Rathore Guide Aayojan School of Architecture,Jaipur

ACKNOWLEDGEMENT I would like to thank my guide, Prof. N.S. Rathore for his continued guidance, encouragement and support throughout this research. I am very grateful to my coordinator, Prof. A.S. Rathore for her valuable time and guidance. I would like to thank all the guides who guided me in the review sessions and gave directions. I would also like to thank my parents without whom not only this year, but my entire architectural education would not have been possible. I thank them for their constant support and encouragement. Last but not the least, all my friends who stood by me throughout this education and guided me at difficult situations.

Yamini Gupta V Year B.Arch. (C) Aayojan School of Architecture, Jaipur

iii

ABSTRACT The last two decades have witnessed a severe energy crisis in developing countries especially during summer season. The energy consumption in buildings is quite high, which also leads to depletion of resources. The use of air conditioning is increasing to achieve thermal comfort. There is hardly any difference observed in the room temperatures. The aim of this study are (a) to identify the various active and passive techniques of the building envelope and how they can help in achieving thermal comfort. (b) to find out which technique can help in attaining large temperature differences. (c) It will also help in recommending the techniques in building envelope and the planning. The different envelope and its components are identified through case studies, surveys. To know the exact data of the temperature difference caused by the envelope components i.e., roofs and walls, thermal analysis is done on ecotect. Various reflective, absorptive materials can be used. The use of local materials and techniques to create facade, roof system are feasible as well as creates thermal comfort. These need to be properly planned to avoid any wastages. External temperature

Internal temperature

CONTENTS Page No. Approval

Declaration

Certificate

Acknowledgement

iii

Abstract

Contents

v-vii

List of illustrations List of table CHAPTER 1: INTRODUCTION

viii-xv xv-xvi

01-06

1.1

Background of the study

02-03

1.2

Criteria of selection

03-04

1.3

Hypothesis

1.4

Aim

1.5

Objectives

1.6

Scope

1.7

Methodology

CHAPTER 2: BUILDING ENVELOPE 2.1

Climate classification

2.2

Thermal comfort 2.2.1 Factors

2.3

2.4

2.5

04 04-05

07-19 08 08-09 09

2.2.2 Passive design features

10-12

Building envelope

12-14

2.3.1 Then

12-13

2.3.2 Now

13-14

Envelope components

14-19

2.4.1 Roof

14-17

2.4.2 Wall

17-18

Design solutions

19 v

CHAPTER 3: ACTIVE AND PASSIVE TECHNIQUES 3.1

Passive Design Techniques

21-25

3.1.1 Building shape

21-22

3.1.2 Open spaces

22-23

3.1.3 Double skin

23-24

3.1.4 Brisle Soliel

24-25

3.1.5 Shaft box type facade 3.2 3.3

3.4

Active design techniques

25-26

3.2.1 Louvers

25-26

Energy efficient buildings

26-31

3.3.1 PEDA Office, Chandigarh

26-28

3.3.2 Indira Paryavaran Bhawan , New Delhi

29-31

Comparative Analysis of case studies 3.4.1 Comparative Analysis based on techniques

3.5

20-35

Questionnaire

CHAPTER 4: THERMAL ANALYSIS

31 31-35 35 36-47 37

4.1

Framework

4.2

Facade

37-43

4.2.1 Standard

37-38

4.2.2 Horizontal (N, S, E, W) 4.2.3 Vertical (N, S, E, W)

38 38-39

4.2.4 Horizontal (S & W), Vertical (E & N)

4.2.5 Horizontal (S & E), Vertical (W & N)

39-40

4.2.6 Vertical (N), Horizontal (S, W, E) 4.2.7 Louvers 4.2.8 Jaali 4.2.9 Brisle soliel (N, S, E, W)

40 40-41 41 41-42

4.2.10 Brisle soliel (S, W), Horizontal (E), Vertical (N)

4.2.11 45 degree brisle soliel (S, W), Vertical (N, E)

4.2.12 45 degree brisle soliel (S, W), Horizontal (E),

43 vi

Vertical (N) 4.2.13 4.3

45 degree brisle soliel (S, W), brisle soliel (E, N)

Roof

43-47

4.3.1 Parapet & tiles

43-44

4.3.2 Courtyard & tiles 4.3.3 Courtyard, tiles, louvers 4.3.4 Dome, tiles, parapet 4.3.5 Double insulation roof, parapet

4.4

5.2

44 44-45 45 45-46

4.3.6 Double insulation roof, courtyard, parapet

4.3.7 Double insulation roof, courtyard, louvers, parapet

4.3.8 Double insulation roof, dome, parapet

4.3.9

Double roof

Inferences

CHAPTER 5:CONCLUSIONS & RECOMMENDATIONS 5.1

Conclusions

47 48-52 49-50

5.1.1 Thesis

5.1.2 Techniques

Recommendations

50-52

5.2.1 Form and orientation

5.2.2 Shading

5.2.3 Insulation

5.2.4 Evaporative cooling

5.2.5 Cool roofs

5.2.6 Roof

5.2.7 Wall

5.2.8 Roof and wall

GLOSSARY OF TERMS

xvii

BIBLIOGRAPHY

xviii-xix

ANNEXURES

xx-xxxi vii

LIST OF ILLUSTRATION Figure No. Title

Page No. Source

Chapter 1 Introduction

1.1

Percentage distribution

1.2

Roofing Techniques 3

nzeb.in

1.3

Single glazing

nzeb.in

1.4

Ventilation

nzeb.in

1.5

Rajasthan School, Ras, Rajasthan

www.archdaily.com

1.6

Elementary school by Krug & Partner, Munich

pinterest.com

1.7

Schematic diagrams for passive and active cooling 5

simscale.com

1.8

Methodoloy

Author

Design bridge https://thedesignbridge.in/blog/climatologyscientific-study-of-climatesand-affecting-factors/

http://article.sapub.org/10.5923.j.arch.2016060 5.01.html

ECBC, 2017

Chapter 2 - Building envelope

2.1

Climatic classification

2.2

Temperature and Humidity

2.3 2.4

Psychrometric chart 9 Average Hourly

https://www.researchgate.net/figure/Psychro metric-chart-Givoni-1992_fig1_327768540 weatherspark.com viii

Temperature 2.5

Orientation

nzeb.in

2.6

Shading design strategies

ECBC, 2017

2.7

Solar angles

Advances in Passive Cooling Design: An Integrated Design Approach

2.8

Atrium ventilation

pinterest.com

2.9

Evaporative cooling 12

nzeb.in

2.1

Shahjanabad

Passive Cooling and Vernacularism in Mughal Buildings in North India

2.11

Stepwell

wikipedia.org

2.12

Fatehpur sikri

tripadvisor.in

2.13

Sketch showing jaali 13

Author

2.14

Overhangs and intricate details

Passive Cooling and Vernacularism in Mughal Buildings in North India

2.15

Section of Pearl academy, Jaipur

pinterest.com

2.16

Pearl academy, Jaipur

pinterest.com

2.17

Reservoir, Rajasthan 14

archmello.com

2.18

Reflective surfaces

https://www.gaf.com/en-us/forprofessionals/resources/cool-roof-solutions

2.19

Extensive green roofs

https://www.buildup.eu/en/learn/ask-theexperts/which-are-different-types-green-roofs

2.2

2.21

Intensive green roof 15

https://www.buildup.eu/en/learn/ask-theexperts/which-are-different-types-green-roofss

Semi Intensive roofs

https://www.buildup.eu/en/learn/ask-theexperts/which-are-different-types-green-roofs

2.22

Roof strategies

A review of roofing methods: Construction features, heat reduction, payback period and climatic responsiveness

2.23

Types of roof ponds

A review of roofing methods: Construction features, heat reduction, payback period and climatic responsiveness

2.26

Stone wall , Brick wall

Author

2.27

Cavity wall

Author

2.28

Rat trap walls

pinterest.com

CHAPTER 3: ACTIVE AND PASSIVE TECHNIQUES 3.1

Ras School Plan

Author

3.2

Anged walls

www.archdaily.com

3.3

Ras School Sections 21

www.archdaily.com

Sakai Gas Building

https://www.researchgate.net/figure/SakaiGas-Building-office-buildingSakai-Japan-temperateclimate_fig2_281169946

3.5

Plan of Sakai Gas Building

https://www.researchgate.net/figure/SakaiGas-Building-office-buildingSakai-Japan-temperateclimate_fig2_281169946

3.6

Indian Habitat centre, Delhi

Author

3.7

Shaded courtyards

Delhi from the 1970s to the present

3.8

Space frame structure

Delhi from the 1970s to the present

3.9

Sunscreens

Delhi from the 1970s to the present

3.4

3.1

Jaali

wikipedia.org

3.11

GRC screens

https://worldarchitecture.org/architectureprojects/ncmp/72-screens-project-pages.html

3.12

Buffer spaces

https://worldarchitecture.org/architectureprojects/ncmp/72-screens-project-pages.htmll

3.13

Plan and sections

Author

3.14

Schematic diagram 24

Author

3.15

Legislative Assembly, Chandigarh

wikipedia.org

3.16

Shaft box type facade

http://www.bestfacade.com/textde/0102_fun d.htm

3.17

Dancing louvers, Delhi

http://inditerrain.indiaartndesign.com/2017/08 /the-dancing-louvres.html

3.18

Sections

3.19

Details

3.2

Peda office, Chandigarh

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.21

Ground floor Plan

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.22

Vaults

3.23

Section through vaults

3.24

3.25

Central atrium

Exterior view

3.26

Space frame structure

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.27

Sectional view

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.28

Roofing details

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.29

Indira Paryavaran Bhawan, Delhi

nzeb.in

3.3

Entrance

nzeb.in

3.31

Ground floor plan

nzeb.in

3.32

Section showing air movement

Author

3.33

Jaalis in the interior

nzeb.in

3.34

Space frame on the atrium 30

nzeb.in

3.35

Roof plan

nzeb.in

3.36

Parameters

Author

3.37

Relationship of techniques

Author

3.38

Passive techniques

Author

3.39

Angled walls

Author

3.4

Trapezoidal roofs

Author

3.41

Stone

pinterest.com

3.42

Brick

pinterest.com

3.43

Vertical slits

Author

3.44

A.C.P sheets

pinterest.com

xii

3.45

Space frame pergolas

Author

3.46

Narrow vertical slits

Author

3.47

Steel and sail cloth

Delhi from the 1970s to the present

3.48

Lakhori bricks

Delhi from the 1970s to the present

3.49

GRC screens

wikipedia.org

3.5

45 degree brisle soliel

wikipedia.org

3.51

Pyramidical and elliptical roofs

Author

3.52

R.C.C structure

Author

3.53

Louvers

wikipedia.org

3.54

Steel

wikipedia.org

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.55

Vaults

3.56

Shell structure

Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India

3.57

Recessed windows

nzeb.in

3.58

Green roof

nzeb.in

3.59

Flyash bricks

pinterest.comm

3.6

Sandstone

pinterest.comm

3.61

Tiles

pinterest.comm

CHAPTER 4: THERMAL ANALYSIS 4.1

Standard

Author

4.2

Horizontal

Author

xiii

4.3

Vertical

Author

4.4

Vertical and Horizontal devices

Author

4.5

Vertical and Horizontal devices

Author

4.6

Vertical and Horizontal devices

Author

4.7

Louvers

Author

4.8

Jaali

Author

4.9

Brisle soliel

Author

4.1

Brisle soliel

Author

4.11

Brisle soliel

Author

4.12

Brisle soliel

Author

4.13

Brisle soliel

Author

4.14

Tiles

Author

4.15

Tiles

Author

4.16

Tiles

Author

4.17

Domes and Tiles

Author

4.18

Double insulation

Author

4.19

Double insulation, courtyards

Author

4.2

Double insulation, courtyards, louvers

Author

4.21

Double insulation, dome

Author

4.22

Double roofs

Author

xiv

4.23

Bar graph of temperature difference

Author

5.1

Washroom location 49

Author

5.2

Cavity wall location 49

Author

5.3

Roof

Author

5.4

Temperature difference graph

Author

5.5

Ecotect Thermal analysis for roof

Author

5.6

Facade

Author

5.7

Temperature difference graph

Author

5.8

Ecotect Thermal analysis for shading devices on facade

Author

5.9

Wall and roof

Author

5.1

Temperature difference graph

Author

CHAPTER 5 CONCLUSIONS AND RECOMMENDATIONS

LIST OF TABLES Table No.

Title

Page No. Source

2.1

Design solutions for composite climate

3.1

Comparative analysis

32 - 35 Author

4.1

Framework

Author

4.2

Standard

Ecotect

4.3

Horizontal

Ecotect

Author

4.4

Vertical

Ecotect

4.5

Vertical and Horizontal devices

Ecotect

4.6

Vertical and Horizontal devices

Ecotect

4.7

Vertical and Horizontal devices

Ecotect

4.8

Louvers

Ecotect

4.9

Jaali

Ecotect

4.1

Brisle soliel

Ecotect

4.11

Brisle soliel

Ecotect

4.12

Brisle soliel

Ecotect

4.13

Brisle soliel

Ecotect

4.14

Brisle soliel

Ecotect

4.15

Tiles

Ecotect

4.16

Tiles

Ecotect

4.17

Tiles

Ecotect

4.18

Domes and Tiles

Ecotect

4.19

Double insulation

Ecotect

4.2

Double insulation, courtyards

Ecotect

4.21

Double insulation, dome

Ecotect

5.1

Techniques

Author

xvi

Introduction

Thermal comfort through envelope design

Page | 1

Introduction

1.1 BACKGROUND OF THE STUDY THE last two decades have witnessed a severe energy crisis in developing countries especially during summer season. The energy consumption in buildings is quite high, because it is believed that the quality of life will increase by their usages. The use of air conditioning is increasing while the use of ancient cooling techniques is decreasing. Due to excessive use of them, depletion in the natural sources of energy is seen. This is done to achieve thermal comfort in buildings. A drastic change is observed in the climatic conditions like severe summers, harsh winters. According to the World watch Institute, buildings consume about 40% of the worldâ&#x20AC;&#x2DC;s energy production. [1] As a result, buildings are involved in producing about 40% of the sulfur dioxide and nitrogen oxides that cause acid rain and contribute to smog formation. Building energy use also produces 33% of all annual carbon dioxide emissions, significantly contributing to the climate changes brought about by the accumulation of this heattrapping gas . In India, the building sector represents about 33% of total electricity consumption. [1]

Fig 1.1 Percentage distribution

In India, there are 6 regions with different climatic zones. These are Hot and dry, Warm and Humid, Cold and sunny, Cold and humid, Composite. Composite climates have long summers. These are the longest and uncomfortable time of the year. Hence, to meet basic comfort requirements, air conditioning is used. But due to their demerits, the passive and active cooling techniques can be taken into consideration which lowers the energy bills, contribute in conserving the natural resources. In cities like Jaipur, there is a glare which makes the surroundings inhabitable. In order to maintain habitable conditions some traditional techniques as well as new technologies are needed to be studied.

Thermal comfort through envelope design

Page | 2

Introduction

Fig 1.2 Roofing Techniques

Fig 1.3 Single glazing

Fig 1.4 Ventilation

1.2 CRITERIA OF SELECTION THESIS Thesis project is Indian Habitat Centre, Jaipur. The basic idea is to propose a sociocultural hub which incorporates state of art facilities and business centres. It has offices, public spaces and is occupied for most of the day. Different techniques have to be integrated with the project to reduce the energy bills. Hence, various cooling techniques such as earth air tunnels, roof sprays, roof ponds, windows, building form, double skin and intelligent living facades can be used to lower down the internal temperature of the building. DISSERTATION 1. Most of the modern buildings donâ&#x20AC;&#x2DC;t respond to the climatic zone, hence more of mechanical cooling is used which harms the environment. It also affects the health of the workers. Thermal comfort through envelope design

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Introduction

2. The envelope of the buildings plays an important role in the aesthetics of the building as well as in preventing the direct sunlight from reaching the interior of the building. It is different from the conventional methods where there is hardly any difference in ambient and the indoor air temperature.

.Fig 1.5 Rajasthan School, Jaipur Indoor temperature can reduce through the passive and active techniques.

Fig 1.6 Elementary school by Krug & Partner, Munich

Research Questions 1. Can we achieve thermal comfort through envelope design in buildings of composite climates? 2. How it can be achieved through shading? 3. Can it be achieved through insulation and reflections? 4. Can it be achieved through nocturnal radiations? 1.3 Hypothesis statement '' Thermal comfort can be achieved in buildings of composite climatic zones through envelope design.'' 1.4 Aim To prove that thermal comfort can be achieved in buildings of composite climatic zones through envelope design.

Thermal comfort through envelope design

Page |4

Introduction

Envelope design as a means of passive cooling is the integrated design of building form and materials as a total system to achieve optimum comfort and energy savings. An optimal design of the building envelope may provide significant reductions in cooling loads-which in turn can allow downsizing of mechanical equipment. [2]

Fig 1.7 Air circulation

1.5 Objectives 1. To study and understand thermal comfort, envelope, its types and elements. 2. To study techniques such as shading, insulation, reflection, radiation, etc. to achieve thermal comfort. 3. To study and analyse through experiments, the impact of solar radiation on identified envelope types in buildings of Jaipur. 4. To conclude and recommend passive design strategies for envelope design in composite climate. 1.6 Scope and limitations 1. The study will include commercial and public use areas. 2. Parameters of the study will be orientation, form, material, texture. 3. The study will include techniques used in buildings with passive and active design. 4. The study will not be bound to timeline aspects and will look forward to adapt to techniques in composite climates. 5. It will not include landscaping, foundations, basements.

Thermal comfort through envelope design

Page |5

1.7 Methodology The research will start with the formulation of hypothesis on the basis of research done and the questions generated by the study. Then the objectives, scope, limitations are set. In the study part the design strategies in the building envelope are studied on the set parameters.

Fig 1.8 Methodology

Thermal comfort through envelope design

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Building Envelope

Thermal comfort through envelope design

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Building Envelope

2.1 CLIMATE CLASSIFICATION India possesses a large variety of climates, ranging from extremely hot desert regions to high altitude locations with severely cold conditions. The country is divided into 5 zones according to NBC, 2016 I. Hot and dry (HD) II. Warm and humid (WH) III. Moderate (MO) IV. Cold and cloudy (C) V. Cold and sunny (CS) VI. Composite (CO) 2.1.1 Composite climate

Fig 2.1 Climatic zones

The composite zone covers the central part of India. Some cities that experience this type of climate are New Delhi, Kanpur and Allahabad. NATURE OF CLIMATE 1. In summer, Day time temperature is 32-45 degrees. In Night time, it is 27- 32 degrees. 2. In winter, Day time temperature is 10-25 degrees. In Night time, it is 4-10 degrees.

Fig 2.2 Temperature and humidity

3. Receives strong monsoon winds from South-east & north-east.

2.2 THERMAL COMFORT Thermal comfort is the condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation. (ANSI/ASHRAE Standard 55). Thermal comfort through envelope design

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Building Envelope

Surveys show that office workers who feel content with their immediate thermal environment are in the end more productive than those who are not.

2.2.1 Factors

Fig2.3 Psychometric chart

There are 3 factors which influence the thermal comfort. Personal variables - Activity, age, clothing, gender. Environmental variables - Temperature, air movement and humidity and the contributing factors are the external factors.

Temperature - This is described as the degree of heat intensity present in air.

Fig 2.4 Average Hourly Temperature

National Building Code of India (NBC) 2005 has determined range of human thermal comfort between 25ยบC to 30ยบC with optimum condition at 27.5ยบC Air Movement - Air movement is easily described as wind. The action of wind is of utmost importance in attaining thermal comfort.

Thermal comfort through envelope design

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Building Envelope

2.2.2 Passive Design Features Passive design sustainable architecture features are elements that are permanently attached to or part of the building design such as building orientation, double skin envelope, sun-shading device, large overhang etc. The active design sustainable architecture features are elements that bring in different results and actively react to the surrounding such as the solar panel, photovoltaic, rainwater harvesting, roof spray, landscape etc.[3] 1.FORM AND ORIENTATION

Fig 2.5 Form and Orientation

BUILDING ORIENTATION - Longer axis (north –south) aligned perpendicular to the prevailing winds. (Buildings can be oriented at an angle between 0° to 30° with respect to the prevailing wind direction 1. COURTYARD ORIENTATION - 45° from the prevailing wind maximizes wind flow into the courtyard and enhances cross ventilation in the building. 2. Recommendation for composite climate (e.g. Delhi and Gurgaon) : 1. Compact form with low S/V ratio is recommended. A square plan with a courtyard would be very effective. 2. A rectangular form with a longer axis along the north-south is the preferred orientation. 3. East and west orientation should be protected by buffer spaces, shaded walls, etc. Thermal comfort through envelope design

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Building Envelope

2. SHADING c

Fig 2.6 Shading design strategies

1. Overhangs (1m deep) on south-oriented windows. 2. An extended roof can provide shade to the entire north and south wall from the noon sun 3. On north sides, vertical blinds and louvers can be provided. 4. Semi-outdoor spaces such as balconies (2.5m â&#x20AC;&#x201C; 3m deep) can be provided. EXAMPLE OF SHADING DEVICE- For a window of h=1.5m, w=3m, Overhang of 840 mm width and fin of length 2.9m can be provided. Fig 2.7 Solar angles

3. NATURAL VENTILATION There are 3 methods to carry out natural ventilation. Thermal comfort through envelope design

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Building Envelope

1. Single-sided ventilation 2. Cross ventilation 3. Stack effect

Fig 2.8 Atrium ventilation

3. EVAPORATIVE COOLING Over the years, traditional wisdom has supported the idea of a water body such as a pond, lake or a fountain to provide a cooling effect to the surrounding environment. This effect lowers the indoor air temperature â&#x20AC;&#x201C; a widely known concept of evaporative cooling.

Fig 2.9 Evaporative cooling

2.3 BUILDING ENVELOPE The building envelope includes all the building components that separate the indoors from the outdoors. Building envelopes include the exterior walls, foundations, roof, windows and doors.[4] 2.3.1 THEN 1. Ventilation

Fig 2.10 a) Small openings for visual connection b) near floor and roof for ventilation c) Junagarh fort

Thermal comfort through envelope design

P a g e | 12

Building Envelope

1. Openings installed for ventilation purposes were seen in Shahjahanabad, India. These were installed near the floor level and near the roof level to let the cool air in from the bottom opening and let the hot air out from the top opening.[5]

Fig 2.11 Stepwell

Fig 2.12 Water pond in Fatehpur Sikri

2. Waterbodies in the building help in modifying the microclimate of the public area. It creates natural ventilation which results in cooling the air. 3. For shading the building, intricate details on the faรงade played an important role. Jaali and overhangs in the faรงade control the light and well as reduce the internal heat gain. 4. The material which was used are local stones, sand, mud. For facade, pink and red sandstone were used. The thickness of wall varies from 18 inch to 27 inch.

Fig 2.13 Sketch showing jaali

Fig 2.14 Overhangs and intricate details

2.3.2 NOW

Fig 2.15 Section of Pearl academy, Jaipur

Fig 2.16 Pearl Academy, Jaipur

Thermal comfort through envelope design

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Building Envelope

The building is protected from the environment by a double skin which is derived from a traditional building element called the ‗Jaali‘ which is prevalent in Rajasthani architecture. The outer skin sits 4 feet away from the building and reduces the direct heat gain through fenestrations. Drip channels running along the inner face of the Jaali allow for passive downdraft evaporative cooling, thus reducing the incident wind temperature.[6] The south facing sides are shaped into open stepped platforms along the site‘s contours further generating landscaped spaces and creating a large community space as the traditional stepped wells had. Fig 2.17 Reservoir, Rajasthan

2.4 BUILDING COMPONENT STRATEGIES 2.4.1 ROOF 1. COOL ROOFS A cool roof is one that has been designed to reflect more sunlight and absorb less heat than a standard roof. Cool roofs can be of a highly reflective type of paint, a sheet covering, or tiles. It involves radiative cooling. [7] Fig 2.18 Reflective surfaces

TEMPERATURE - Traditional dark roofs reach temperatures of 66ºC or more in the summer sun, in contrast a cool roof under the same conditions could stay more than 28ºC cooler. MATERIALS - Broken china - mosaic, modified bitumen with plastic and a layer of reinforced material, Concrete and clay tiles[7] Thermal comfort through envelope design

Page | 14

Building Envelope

2. GREEN ROOFS 1. Extensive green roofs - These are developed for ecological and aesthetical purposes. These are thin growing mediums (4-8 inches) and lightweight. These are ideal for schools, housing.

Fig 2.19 Extensive green roof

2. Intensive green roofs -They have thick growing Mediums (8-12 inches) .They provide additional Open spaces to people. Fig 2.20 Intensive green roof

3. Semi intensive roofs - These are combination of both intensive and extensive roofs. These methods provide insulation to the roof. The ambient air temperature reduces by 7 â&#x2014;ŚC due to green roofs and the surface temperature of the roof reduces by 24.5 â&#x2014;ŚC.[8]

Fig 2.21 Semi intensive roof

4. DOUBLE ROOFS -This method aims to reduce heat flux in building roofs by using double layers with a gap between them. -The first layer works as a reflector/absorber for heat, and the second layer covers the internal spaces. -The gap works as an insulation layer to prevent the heat transfer between the addressed layers. -This method can reduce heat gains up to 71%. [8]

Thermal comfort through envelope design

Page | 15

Building Envelope

Roof ponds

Fig 2.22 Roof strategies

Thermal comfort through envelope design

Page | 16

Building Envelope

Fig 2.23 Types of roof ponds

2.4.2 WALLS 1. SOLID WALLS -Solid walls can be insulated either from the inside or the outside. Thermal comfort through envelope design

Page | 17

Building Envelope

-Material: stone, earth, burnt clay brick, concrete. -Insulation: Outside of wall gives four times more time lag than the inside.

Fig 2.24 Stone wall, Brick wall

2. CAVITY WALLS -A cavity wall is composed of two masonry walls separated by an air space which gives insulation. -Material: The outer wall is made of brick and faces the outside of the building structure. The inner wall may be constructed of masonry units such as concrete block, structural clay, brick or reinforced concrete. These two

Fig 2.25 Cavity wall

walls are fastened together with metal ties or bonding - blocks. The ties strengthen the cavity wall. 3. RAT TRAP WALLS -The bricks are placed in vertical position, so that 110 m face is seen from front elevation, instead of the 75mm face (considering brick of standard size 230 X 110 X 75 mm). -Since width of wall remains 230mm, an internal cavity is created. This is where approximately 30% material (brick and mortar) is saved and thus overall construction cost is reduced. -Cavity provides effective thermal and sound insulation. This makes rat trap bond energy and cost efficient building technology.

Fig 2.27 Rat

Fig 2.26 Rat trap wall

Thermal comfort through envelope design

Page | 18

Building Envelope

2.5 DESIGN SOLUTIONS Sources of heat

Actions required

Design solution

Direct heat gain from

Avoidance

1. Shading devices

solar radiation on

2. Self-shading building form

building envelope

3. Landscape design

materials

4. Urban design Slowing

1.Thermal mass 2. Insulation 3. Material 4. Color

Direct heat gain from

Avoidance

solar radiation on

2. Reflective materials and glass

windows and glazed

3. Orientation design

surfaces

Indirect heat gain by

1. Shading devices

Slowing

1. Double glazing

Avoidance

1. Landscape

conduction with

2. Orientation

outdoor environment through building envelope. Slowing

1. Insulation

Removal

1. Orientation 2. Implement removal devices

Table 2.1 Design solutions for composite climate

Thermal comfort through envelope design

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Building Envelope

Thermal comfort through envelope design

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Techniques

3.1 PASSIVE DESIGN Passive design is design that takes advantage of the climate to maintain comfortable temperature range. It uses layout, fabric and form to reduce or remove mechanical cooling, heating, ventilation and lighting demand. In this section buildings are analysed on the basis of parameters like building shape, ventilation paths, open spaces etc. One or two parameters which are dominant are taken into account and further studied.[9] 3.1.1 BUILDING SHAPE The orientation and the form of the building elements like walls greatly determines the heat entering in the building. Some of the parameters are1. Sun shading form - Ras School, Jaipur

Fig 3.2 Angled walls

Angled walls which are projected by 2m act as sun breakers to reduce heat gain from the south sides generating cooler internal Fig. 3.1 Ras School Plan

spaces.External wall - 450 mm thick stone walls (external)

External wall thickness is 450 mm and is made from stone.

Fig 3.3 Section

Page | 21

Techniques

2. Ventilation path - Sakai Gas Building, Japan The Sakai Gas Building utilizes a ventilation path with open spaces of width 1m placed between divided masses which represent a repetitive rhythm. This building is an excellent case that could be applied to office buildings in urban centers.[10]

Fig 3.4 Plan showing circulation

Fig3.5 Sakai gas building

3.1.2 OPEN SPACES Open spaces control the microclimate of the area by use of materials, shading techniques. 1. Shaded courtyards - Indian Habitat Centre, Delhi In order to reduce solar heat gain, the building volumes are organised around shaded courtyards. These courtyards are covered by sun-screen pergolas suspended from a space frame structure .[11]

Fig 3.6 Indian Habitat Centre, Delhi

Fig3.7 Shaded courtyards

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Techniques

Technological Stability The sun-screen pergolas contain angled panels designed to block the summer sun while letting in the winter sun. Moreover, the pergolas shade not only the courtyards below but also the inner facades of the building volumes. [11] These are made from hundreds of panels suspended from large space frames. Material -sailcloth Fig 3.8 Space frame structure

Fig 3.9 Sunscreen

3.1.3 DOUBLE SKIN - 72 screens, Jaipur The entire facade of the building is sheathed in contemporary reinterpretations of the traditional â&#x20AC;&#x2014;jaaliâ&#x20AC;&#x2DC; on all the sides. Air is forced through small openings, cooling air, increasing its force marginally. It reduces heat gain, increase ventilation. Fig 3.10 Jaali

GRC Screens These glass-reinforced concrete screens further reduce heat gain and render the building very energy efficient. The screens are supported by a steel framework with projections that vary from 0.9 to 1.5 m.

Plantations as Heat Insulators

Fig 3.11 GRC Screens

The steel framework creates an external periphery space for plants at each level that will act as further insulation from the external heat creating cooler office spaces within. Fig 3.12 Buffer spaces

Page | 23

Techniques

The washrooms and staircases are on the south side of the building while the working desks are on the north side of the building.

Fig 3.13 Plan and sections

3.1.4 BRISLE SOLIEL Brise soleil in French means â&#x20AC;&#x2014;sun

breakerâ&#x20AC;&#x2DC;. It refers to permanent sun-shading techniques ranging from the simple patterned concrete walls. Fig 3.14 Schematic diagram

The sunbreakers generate shade to prevent the high-angle summer sun falling on the facade, but also allow the low angle winter sun to provide some passive solar heating. [16] LEGISLATIVE ASSEMBLY, CHANDIGARH Year of completion - 1962 Architect - Le Corbusier Use of the brise soleil cuts direct radiation from coming inside the building.

Fig 3.15 Legislative Assembly, Chandigarh

At the outermost layer of the space and along the edges of the building, there are many supporting offices and committee rooms, which are covered by large sun protecting louvers or brise soleil for protecting glazing against sun. [16] Page | 24

Techniques

PEOPLE OPINION Glare protection is also good with adequate natural light in the offices. Monsoon and early summer are comfortable in the offices inside the building. On very hot humid summer days it is sufficiently comfortable with the help of fans in these spaces. [16]

3.1.5 SHAFT BOX TYPE FACADE The objective of this partitioning concept is to encourage natural ventilation by adapting the partitioning of the facade so as to create an increased stack effect.

Fig 3.16 Shaft box type facade

3.2 ACTIVE DESIGN 3.2.1 Louver The louver is a sunscreen system that forms a repetitive pattern, creating a unified image of the faรงade. The faรงade design differs depending on the form and arrangement of the louver and tends to emphasize the horizontal element on the south side and vertical element on the eastwest side according to the height of the sun. The Dancing Louvers, New Delhi Year of completion - 2017 The vertical fin louvered elements act as a solar shading device particularly with the sun angle facing the faรงade. Fig 3.17 Dancing Louvers, Delhi

Page | 25

Techniques

The Transformation of an abandoned warehouse into a aero-component design studio and admin office becomes a meticulously surgical act of inserting technically expressive, delicate and lightweight implants play of steel and concrete.

Fig 3.18 Section

Fig 3.19 Details

3.3 ENERGY EFFICIENT BUILDINGS Different cases are taken and studied on many parameters like orientation, techniques used for insulation on roofs, walls, shading techniques, etc. 3.3.1 PEDA, CHANDIGARH Architect - Prof. Dr. Arvind Krishan Year of completion- 2004

Fig 3.20 Peda office, Chandigarh

Climate - Composite Site area - 1.5 acre Built up area - 7,430 sq m Page | 26

Building Envelope

Punjab Energy CHANDIGARH Development Agency (PEDA), Chandigarh is a state nodal agency responsible for development of new & renewable energy and non-conventional energy in the state of Punjab.[12] Orientation: Solar Passive Complex has been developed in response to solar geometry i.e. minimizing solar heat gain in cold period. The building envelope [13] attenuates the outside ambient conditions and the large volume of air is naturally conditioned by controlling solar access in response to the climatic swings.[12]

Fig 3.21 Ground floor Plan

Cavity Walls The complex is a single envelope made up of its outer walls as double skin walls having 2â&#x20AC;&#x2013; cavity in between. The cavity walls facing south and west are filled with further insulation material for efficient thermal effect. [12] Light Vaults

activated naturally ventilating, domical

Fig 3.22 Vaults in the exterior

The verticalincutouts in the floating slabs structures the south to admit day lightare integrated withand lightheat. vaults and solar without glare activated naturally ventilating, domical structures in the south to admit day light without glare and heat. [12]

Fig 3.23 Section through vaults

Thermal comfort through envelope design

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Building Envelope

Fig 3.24 Central atrium

Fig 3.25 Exterior view

Unique Shell Roofing on Central Atrium The Central atrium of the complex having main entrance, reception, water bodies, cafeteria and sitting place for visitors constructed with hyperbolic shell roof to admit daylight without glare and heat coupled with defused lighting

Fig 3.26 Space frame structure

through glass to glass solar panels. The roof is supported with very light weight space frame structure

Wind tower

Shell roof Light vaults

Fig 3.27 Sectional view

Insulated roofing: All the roofs have been insulated with double insulation system to avoid penetration of heat from the roof.

Fig 3.28 Roofing details

Thermal comfort through envelope design

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Building Envelope

3.3.2 INDIRA PARYAVARAN BHAWAN MINISTRY OF ENVIRONMENT AND FOREST (MOEF)

Fig 3.29 Indira Paryavaran Bhawan, Delhi

Location

Fig 3.30 Entrance

- NewDelhi

Occupancy Type - Office Climate Type

- Composite

Project Area

- 9565 m2

Year of completion - 2014 Indira Paryavaran Bhawan, the headquarters of the Ministry of Environment, Forests and Climate Change, in Jorbagh, New Delhi, was constructed by the Central Public Works Department (CPWD) as project management agency. It is the first on site net zero builing in India. Indira Paryavaran Bhawan uses 70% less energy compared a conventional building. [15] Orientation Building is north south oriented, with separate blocks connected through corridors and a huge central courtyard.

Fig 3.31 Ground floor plan

Ventilation Central courtyard helps in air movement as natural ventilation happens due to stack effect. Windows and jaalis add to cross ventilation. [15]

Thermal comfort through envelope design

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Building Envelope

Fig 3.32 Section showing air movement

Fig 3.33 Jaalis in the interior

Fig 3.34 Space frame on the atrium

Roof There is a provision of solar voltaics for net zero requirement which also shades the roof. Photovoltaics step towards south side to gain maximum solar energy.

Fig 3.35 Roof plan

Materials- Fly Ash Brick , Aerated Autoclaved Cement (AAC) Block , Portland Puzzolona Cement ( with 30 % fly ash ), Cool roofs with high SRI tiles ,Local Stone with Marble Strips, Dholpur stone for cladding fly ash bricks for 2 storeys.

Thermal comfort through envelope design

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Building Envelope

z Local availability of materials viz. Kota stone, marble from Rajasthan, Jhansi granite, and simultaneously avoiding granite from afar, say South India. The reduction in operational energy by reduced HVAC load occurs by utilizing good insulation in the building interiors, for instance, AAC blocks for the walls have been chosen. High albedo tiles are used on the roof and UPVC windows with composite sections are used for better insulation which reduces the cooling requirement of the building.[15] 3.4 COMPARATIVE ANALYSIS OF CASE STUDIES

Fig 3.36 Parameters

Fig 3.37 Relationship of techniques

Fig 3.38 Passive Techniques

3.4.1 COMPARATIVE ANALYSIS OF CASE STUDIES ON THE BASIS OF TECHNIQUES Thermal comfort through envelope design

P a g e | 31

Table 3.1 Comparative Analysis

CASE STUDY

ORIENTATION, FORM, CHARACTER

MATERIAL, ITS COLOR & NATURE

1. Rajasthan

ANGLED WALLS

STONE

1. Sun barriers in south and west direction.

1. WALL - 450 MM Stone wall

2. Angled Walls -Projected by 2m from the main building.

2.Medium , rough and absorptive.

School, Nagaur, Rajasthan

3. Boxing on North side ROOF FRAMES

Fig 3.41 Stone Fig 3.39 Angled walls

BRICK

4. Linear trapezoidal frames over walkways.

1. 230 mm brick walls

5. Courtyard act as a buffer space.

2.Light, rough and reflective Fig 3.42 Brick

Fig 3.40 Trapezoidal roofs

2. Sakai Gas Building, Japan

1. Barriers against sunlight in South direction

1.ACP sheets

2. Narrow vertical slits with openings of width 1m.

2. Light, smooth and reflective

3.Projected walls and roofs Fig 3.43 Vertical slits

ROOF TRUSS 3. Indian Habitat Centre, Delhi

Fig 3.44 ACP sheets

ROOF TRUSS

1. North- south orientation 1.Steel and sail cloth. 2.Roof -space frame pergolas over courtyards, open spaces 2. Light, reflective. Fig 3.45 Space frame pergolas

WALLS

Fig 3.47 Steel and sail cloth

FACADE TREATMENT 1. Cavity walls made from Lakhori bricks. 3. Projections over top 2 floor windows 2. Rough, Medium, absorptive 4. Walls - Narrow vertical slits 3. Brushed stone aggregate

5. Roof gardens, planter boxes

Plaster for interior of the Fig 3.46 Narrow vertical slits

Fig 3.48 Lakhori bricks

building. P a g e | 32

4. 72 screens, Jaipur

1.Building orientation- N S direction

1.GRC (Glass Reinforced

2. Jaalis projected by 1m from the main building.

Concrete) screens - 40 mm

3. Buffer spaces( 0.9 - 1.5 m )act as cavity between

thick.

the wall and the jaali facade. 2. Light , smooth, reflective Fig 3.49 GRC screens Fig 3.12 Buffer spaces

5. The Legislative Assembly, Chandigarh

FACADE

1. R.C.C( Reinforced concrete)

1.Brisle soliel in North- West, South - West, North East. 2. 45 degree from the main building on NW & SW direction. 1. Brisle soliel of depth 2m.

Fig 3.50 45 degree Brisle Soliel

Fig 3.52 R.C.C structure

ROOF 1.Double roof - The space between the two roofs is left open between flat roof and parasol roof. 2. Pyramidical and elliptical roofs are there in some areas of flat roofs.

6. The Dancing

Fig 3.51 Pyramidical and elliptical roofs

1. Steel

1.Louvers in North and West direction

Louvres, New Delhi 2. Louvers with perforations- A peripheral void running around the industrial office creates an environmental buffer that assists climatically. Fig 3.54 Steel Fig 3.53 Louvers

Page | 33

7. PEDA office

1. Dome shaped structures in South- West.

SHELL ROOF

building,

1.EPS(Extruded polystyrene ),

Chandigarh

FRP( Fibre Reinforced Plastic ) DOUBLE ROOF Fig 3.55 Vaults

2.10 cm thick Hyperbolic shell roof

1. Brick tiles 2. Mud phuskas 3. Ferrocement 4. Rockwool Fig 3.56 Shell structure

5. R.C.C

FACADE

WALL AND ROOF

Paryavaran

1. Recessed windows in all directions.

1.R.C.C( Reinforced concrete)

Bhawan , New

2. Lightshelves in East , West and South.

Delhi

3. Double - glazed windows.

8. Indira

2. Sandstone for jaali 3. Steel and solar panels 4. Dholpur stone for cladding of Fly ash bricks Fig 3.57 Recessed windows

ROOF 1. Solar PV roof projected by 3 metres on all sides. Fig 3.59 Flyash bricks

Fig 3.60 Sandstone

2.Cool and green roof treatment. 5. Sri tiles for cool roofs

Fig 3.58 Green roof

Fig 3.61 Tiles

Page | 34

Building Envelope

ANALYSIS

ORIENTATION, FORM, CHARACTER

MATERIAL, NATURE

TECHNIQUES

ROLE

Table 3.2 Analysis

3.5 QUESTIONNAIRE 1. OBJECTIVES UNDER RESEARCH- To study techniques such as shading, insulation, reflection, radiation to achieve thermal comfort. 2. OBJECTIVES FOR SURVEY- To know about the awareness of the techniques to achieve thermal comfort in the building envelope. 3. AREA OF STUDY - Delhi, Jaipur 4. There are 2 survey conducted. First survey is from architects while second is from people working in offices. Refer Annexure Thermal comfort through envelope design https://forms.gle/QhaRrdvwXDWD9oSF7, https://forms.gle/sEjqjYumX9MFpy9Z8

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Building Envelope

Thermal comfort through envelope design

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Thermal analysis

4.1 FRAMEWORK CUBE ( 10 m X 10m X 10m) Difference in the temperature of the interior at different hours of the day ( 17th June) is observed.

FACADE ANALYSIS

Orientation,form, material

ROOF ANALYSIS

COMBINATION 1 - Horizontal &

COMBINATION 1 - Tiles

vertical shading devices

1. Parapet & tiles

1. Horizontal ( N, S , E, W )

2. Courtyard &tiles

2. Vertical ( N, S , E, W )

3. Courtyards, tiles & louvers

3. Horizontal ( S & W), Vertical ( E & N )

4. Skylight, tiles & parapet

4. Horizontal ( S & E ), Vertical (W & N ) 5. Vertical ( N ), Horizontal ( S, W, E )

COMBINATION2-Double

COMBINATION 2 - Second skin

insulation roof

1. Louvers

1. Double insulation & parapet.

2. Jaali

2. Double insulation, courtyard

COMBINATION 3 - Brisle soliel

& parapet.

1. Brisle soliel ( N, S, E, W )

3. Double insulation,

2. Brisle soliel ( S, W ), Horizontal ( E ),

courtyard, louvers & parapet.

Vertical ( N )

4. Double insulation, dome &

3. Brisle soliel ( S, W ), Vertical ( N, E )

parapet.

4. 45 degree Brisle soliel ( S, W ), Vertical ( N, E )

COMBINATION 3 - Double roof

5. 45 degree Brisle soliel ( S, W ),

1. Double roof

Horizontal ( E ), Vertical ( N ) 6. 45 degree Brisle soliel ( S, W ), Brisle soliel ( E, N ) Table 4.1 Framework

4.2 FACADE Different techniques for shading, insulation are experiment on the cube. 4.2.1 STANDARD Thermal comfort through envelope design

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Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35.6

37.8

2.2

6.2

10:00 36.3

38.8

2.5

6.9

11:00 38.1

39.7

1.6

4.2

12:00 40.2

40.5

0.3

0.7

13:00 41.3

41.4

0.1

0.2

14:00 41.5

42.2

0.7

1.7

15:00 41.6

42.7

1.1

2.6

16:00 41.5

42.6

1.1

2.7

According to this data,

17:00 41.9

41.8

-0.1

-0.2

cooling is required in between

18:00 42.8

40.2

-2.6

-6.1

12 PM to 2 PM.

Fig 4.1 Standard

No external shading devices and are used in this case.

Table 4.2 Standard

4.2.2 HORIZONTAL (N, S, E, W) Horizontal shading devices of width 0.7 m are provided on all 3 floors.

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35.6

37.8

-2.2

6.2

10:00 36.3

38.8

-2.5

6.9

11:00 38.1

39.7

-1.6

4.2

12:00 40.2

40.5

-0.3

0.7

13:00 41.3

41.4

-0.1

0.2

14:00 41.5

42.2

-0.7

1.7

15:00 41.6

42.7

-1.1

2.6

16:00 41.5

42.6

-1.1

2.7

17:00 41.9

41.8

0.1

-0.2

18:00 42.7

40.2

2.5

-5.9

Fig 4.2 Horizontal

Case 1 - When plaster is used on the exterior walls, then average decrease is 1.22 degree.

Table 4.3 Horizontal

Case 2 - When cavity wall is used for insulation, then average decrease is 3.22 degrees. 3. VERTICAL (N, S, E, W) When vertical shading devices of width 1m are used on all four sides, these are observed Thermal comfort through envelope design

Page | 38

Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35

37.8

-2.8

8.0

10:00 35.2

38.8

-3.6

10.2

11:00 36.4

39.7

-3.3

9.1

12:00 37.2

40.5

-3.3

8.9

13:00 38.6

41.4

-2.8

7.3

14:00 39

42.2

-3.2

8.2

15:00 40.2

42.7

-2.5

6.2

16:00 41.5

42.6

-1.1

2.7

17:00 41.9

41.8

0.1

-0.2

degrees is achieved with

18:00 42.7

40.2

2.5

-5.9

concrete plaster.

Fig 4.3 Vertical

An average decrease of 3

Table 4.4 Vertical

4.2.4 HORIZONTAL (S & W), VERTICAL (E & N) When vertical shading devices of width 1m are used on 2 sides, these are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 36.1

37.8

-1.7

4.71

10:00 36.3

38.8

-2.5

6.89

11:00 36.7

39.7

-3

8.17

12:00 38

40.5

-2.5

6.58

13:00 39.6

41.4

-1.8

4.55

14:00 40.3

42.2

-1.9

4.71

15:00 40.5

42.7

-2.2

5.43

16:00 40.5

42.6

-2.1

5.19

17:00 40.4

41.8

-1.4

3.47

18:00 40.7

40.2

0.5

-1.23

Fig 4.4 Vertical and Horizontal devices

An average decrease of 2 degrees is achieved with concrete plaster.

Table 4.5 Vertical and horizontal devices

4.2.5 HORIZONTAL (S & E), VERTICAL (W & N) When vertical shading devices of width 1m are used on 2 sides, these are observed. An average decrease of 2.8 degrees is achieved with concrete plaster.

Thermal comfort through envelope design

Page | 39

Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35

37.8

-2.8

8.00

10:00 35.2

38.8

-3.6

10.23

11:00 35.6

39.7

-4.1

11.52

12:00 36.2

40.5

-4.3

11.88

13:00 37.6

41.4

-3.8

10.11

14:00 40

42.2

-2.2

5.50

15:00 40.6

42.7

-2.5

6.16

16:00 40.8

42.6

-2.2

5.39

17:00 40.4

41.8

-1.4

3.47

18:00 40.8

40.2

0.6

-1.47

Fig 4.5 Vertical and Horizontal devices

Table 4.6 Vertical and horizontal devices

4.2.6 VERTICAL (N), HORIZONTAL (S, W, E) When vertical shading devices of width 1m are used on 1 side, these are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35

37.8

-2.8

8.00

10:00 35.2

38.8

-3.6

10.23

11:00 35.6

39.7

-4.1

11.52

12:00 37.2

40.5

-3.3

8.87

13:00 38.6

41.4

-2.8

7.25

14:00 40

42.2

-2.2

5.50

15:00 40.6

42.7

-2.1

5.17

Fig 4.6 Vertical and Horizontal devices

16:00 40.8

42.6

-1.8

4.41

An average decrease of 2.3

17:00 40.6

41.8

-1.2

2.96

degrees is achieved with

18:00 41.8

40.2

1.6

-3.83

concrete plaster.

Table 4.7 Vertical and horizontal devices

4.2.7 LOUVERS When louvers are there on all four sides, there is a 2m cavity between main building and the louvers. An average decrease of 2.5 degrees is achieved with concrete plaster.

Thermal comfort through envelope design

Page | 40

Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35.4

37.8

-2.4

6.78

10:00 35.4

38.8

-3.4

9.60

11:00 35.8

39.7

-3.9

10.89

12:00 36.4

40.5

-4.1

11.26

13:00 37.6

41.4

-3.8

10.11

14:00 40

42.2

-2.2

5.50

15:00 40.6

42.7

-2.1

5.17

16:00 40.8

42.6

-1.8

4.41

17:00 40.4

41.8

-1.4

3.47

18:00 40.8

40.2

0.6

-1.47

Fig 4.7 Louvers

Table 4.8 Louvers

4.2.8 JAALI When jaali is there on all four sides, there is a 2m cavity between main building and the jaali then following are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 35.5

37.8

-2.3

6.48

10:00 36.8

38.8

-2

5.43

11:00 38.6

39.7

-1.1

2.85

12:00 39.6

40.5

-0.9

2.27

13:00 40

41.4

-1.4

3.50

14:00 40.2

42.2

-2

4.98

15:00 40.2

42.7

-2.5

6.22

16:00 40.5

42.6

-2.1

5.19

An average decrease of 2.0

17:00 41.2

41.8

-0.6

1.46

degrees is achieved with

18:00 41.1

40.2

0.9

-2.19

concrete plaster.

Fig 4.8 Jaali

Table 4.9 Jaali

4.2.9 BRISLE SOLIEL (N, S, E, W) When brisle soliel is there on all four sides, of width 2m then following are observed. Case I- Decrease of 2.2 degrees is achieved. Case II- Decrease of 4.2 degrees (Cavity walls). Fig 4.9 Brisle soliel

Thermal comfort through envelope design

Page | 41

Thermal analysis PERCENTAGE TIME INSIDE OUTSIDE DIFFERENCE %

PERCEN TIME INSIDE OUTSIDE DIFFERENCE TAGE %

09:00 35.6

37.8

-2.4

6.74

09:00

36.2

37.8

-1.6

4.42

10:00 35.8

38.8

-3

8.38

10:00

36.1

38.8

-2.7

7.48

11:00 36.4

39.7

-3.3

9.07

11:00

36.1

39.7

-3.6

9.97

12:00 37.4

40.5

-3.1

8.29

12:00

35.8

40.5

-4.7

13.13

13:00 38.8

41.4

-2.6

6.70

13:00

35.9

41.4

-5.5

15.32

14:00 40

42.2

-2.2

5.50

14:00

36.1

42.2

-6.1

16.90

15:00 40.6

42.7

-2.1

5.17

15:00

36.6

42.7

-6.1

16.67

16:00 40.8

42.6

-1.8

4.41

16:00

37.3

42.6

-5.3

14.21

17:00 40.4

41.8

-1.4

3.47

17:00

37.7

41.8

-4.1

10.88

18:00 40.8

40.2

0.6

-1.47

18:00

37.8

40.2

-2.4

6.35

Table 4.10 Case 1 of brisle soliel

Table 4.11 Case 2 of brisle soliel

4.2.10 BRISLE SOLIEL (S, W), HORIZONTAL (E), VERTICAL (N) When brisle soliel of width 2m are provided then following are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 9

37.8

-2.8

8.00

35.1

38.8

-3.7

10.54

35.4

39.7

-4.2

11.86

37.4

40.5

-3.1

8.29

38.8

41.4

-2.8

7.22

42.2

-2.2

5.50

40.6

42.7

-2.1

5.17

Fig 4.10 Brisle Soliel

40.8

42.6

-1.8

4.41

40.8

41.8

-1

2.45

An average decrease of 2.3

40.9

40.2

0.7

-1.71

degrees is achieved.

Table 4.12 Brisle soliel

4.2.11

45 DEGREE BRISLE SOLIEL (S, W), VERTICAL (N, E)

When brisle soliel are at 45 degree from the main building, then following are observed. An average decrease of 1.6 degrees is observed when concrete plaster is used. Fig 4.11 Brisle Soliel

Thermal comfort through envelope design

P a g e | 42

Thermal analysis

4.2.12 45 DEGREE BRISLE SOLIEL (S, W), HORIZONTAL (E), VERTICAL (N) When brisle soliel are at 45 degree from the main building, then following are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 36.4

37.8

-1.4

3.85

10:00 36.3

38.8

-2.5

6.89

11:00 36.3

39.7

-3.4

9.37

12:00 36.1

40.5

-4.4

12.19

13:00 36.1

41.4

-5.3

14.68

14:00 36.3

42.2

-5.9

16.25

15:00 36.8

42.7

-5.9

16.03

16:00 37.4

42.6

-5.2

13.90

An average decrease of 4

17:00 37.8

41.8

-4

10.58

degrees is observed

18:00 37.9

40.2

-2.3

6.07

when cavity walls is used.

Fig 4.12 Brisle Soliel

Table 4.13 Brisle soliel

4.2.13

45 DEGREE BRISLE SOLIEL (S, W), BRISLE SOLIEL (E, N)

When brisle soliel are at 45 degree from the main building , then following are observed. TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE % 09:00 36.8

37.8

-1

2.72

10:00 36.8

38.8

-2

5.43

11:00 36.7

39.7

-3

8.17

12:00 36.5

40.5

-4

10.96

13:00 36.6

41.4

-4.8

13.11

14:00 36.7

42.2

-5.5

14.99

15:00 37.2

42.7

-5.5

14.78

Fig 4.13 Brisle Soliel

16:00 37.8

42.6

-4.8

12.70

An average decrease of

17:00 38.1

41.8

-3.7

9.71

3.6 degrees is observed

18:00 38.1

40.2

-2.1

5.51

when cavity wall is used.

Table 4.14 Brisle soliel

4.3 ROOF Different techniques for shading, insulation are experiment on the cube. 4.3.1 PARAPET & TILES

Thermal comfort through envelope design

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Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 35

37.8

-2.8

7.4

10:00 35.6

38.8

-3.2

8.2

11:00 36

39.7

-3.7

9.3

12:00 37.4

40.5

-3.1

7.7

13:00 40

41.4

-1.4

3.4

14:00 41

42.2

-1.2

2.8

15:00 41.2

42.7

-1.5

3.5

16:00 41.4

42.6

-1.2

2.8

17:00 41.4

41.8

-0.4

1.0

18:00 40

40.2

-0.2

0.5

Fig 4.14 Tiles

An average decrease of 1.9 degrees is observed.

Table 4.15 Tiles

4.3.2 COURTYARD & TILES TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 34.1

37.8

-3.7

10.9

10:00 34.9

38.8

-3.9

11.2

11:00 37.4

39.7

-2.3

6.1

12:00 40

40.5

-0.5

1.3

13:00 41.1

41.4

-0.3

0.7

14:00 40.8

42.2

-1.4

3.4

15:00 40.7

42.7

-2

4.9

An average decrease of 1.5

16:00 40.4

42.6

-2.2

5.4

degrees is observed when

17:00 40.9

41.8

-0.9

2.2

tiles and courtyards are

18:00 42.1

40.2

1.9

-4.5

there on roof.

Fig 4.15 Tiles

Table 4.16 Tiles

4.3.3 COURTYARD, TILES, LOUVERS An average decrease of 2.7 degrees is observed when tiles, courtyards, louvers are there on roof.

Fig 4.16 Tiles

Thermal comfort through envelope design

Page | 44

Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 34.8

37.8

-3

8.6

10:00 35

38.8

-3.8

10.9

11:00 35.6

39.7

-4.1

11.5

12:00 37.4

40.5

-3.1

8.3

13:00 39.2

41.4

-2.2

5.6

14:00 39.9

42.2

-2.3

5.8

15:00 39.7

42.7

-3

7.6

16:00 39.7

42.6

-2.9

7.3

17:00 39.5

41.8

-2.3

5.8

18:00 40

40.2

-0.2

0.5

Table 4.17 Tiles

4.3.4 DOME, TILES, PARAPET TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 33.8

37.8

-4

11.8

10:00 34.6

38.8

-4.2

12.1

11:00 36.9

39.7

-2.8

7.6

12:00 39.1

40.5

-1.4

3.6

13:00 40.1

41.4

-1.3

3.2

An average decrease of 1.7 degrees is observed when tiles,

14:00 40.1

42.2

-2.1

5.2

15:00 40.7

42.7

-2

4.9

16:00 41.3

42.6

-1.3

3.1

17:00 42.7

41.8

0.9

-2.1

18:00 42.3

40.2

2.1

-5.0

Fig 4.17 Domes and Tiles

dome shaped skylight of glass are there on roof.

Table 4.18 Tiles

4.3.5 DOUBLE INSULATION ROOF, PARAPET An average decrease of 3.4 degrees is observed when double insulation system are used.

Fig 4.18 Double insulation

Thermal comfort through envelope design

Page | 45

Thermal Analysis

TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 35.6

37.8

-2.2

6.2

10:00 35.8

38.8

-3

8.4

11:00 36

39.7

-3.7

10.3

12:00 36.4

40.5

-4.1

11.3

13:00 37.8

41.4

-3.6

9.5

14:00 38

42.2

-4.5

11.8

15:00 38.2

42.7

-4.5

11.8

16:00 38.4

42.6

-4.2

10.9

17:00 38.6

41.8

-3.2

8.3

18:00 39.4

40.2

-0.8

2.0

Table 4.19 Double insulation roof

4.3.6 DOUBLE INSULATION ROOF, COURTYARD, PARAPET TIME INSIDE OUTSIDE DIFFERENCE PERCENTAGE% 09:00 35.6

37.8

-2.2

6.2

10:00 35.6

38.8

-3.2

9.0

11:00 35.4

39.7

-4.3

12.1

12:00 35.2

40.5

-5.3

15.1

13:00 35.4

41.4

-6

16.9

14:00 35.8

42.2

-6.4

17.9

15:00 36.6

42.7

-6.1

16.7

An average decrease of 4.7

16:00 36.8

42.6

-5.8

15.8

degrees is observed when double

17:00 37.2

41.8

-4.6

12.4

insulation systems,

18:00 37.4

40.2

-2.8

7.5

courtyard are there on roofs.

Fig 4.19 Double insulation, courtyards

Table 4.20 Double insulation roof, courtyards

4.3.7 DOUBLE INSULATION ROOF, COURTYARD, LOUVERS, PARAPET An average decrease of 3.2 degrees is observed when double insulation systems, courtyard, louvers are there on the roofs.

Fig 4.20 Double insulation, courtyards, louvers

Thermal comfort through envelope design

Page | 46

Thermal analysis

4.3.8 DOUBLE INSULATION ROOF, DOME, PARAPET

TIME

INSIDE OUTSIDE DIFFERENCE

PERCENTAGE%

09:00 34.6

37.8

-3.2

9.2

10:00 35

38.8

-3.8

10.9

11:00 35.2

39.7

-4.5

12.8

12:00 36.4

40.5

-4.1

11.3

13:00 37.8

41.4

-3.6

9.5

14:00 38.8

42.2

-3.4

8.8

15:00 38.8

42.7

-3.9

10.1

16:00 39

42.6

-3.6

9.2

degrees is observed when

17:00 40

41.8

-1.8

4.5

double insulation systems,

18:00 41.4

40.2

0.8

-1.9

dome are there on roofs.

Fig 4.21 Double insulation, dome

An average decrease of 3.1

Table 4.21 Double insulation roof, dome

4.3.9 DOUBLE ROOF An average decrease of 3.3 degrees is observed when double roofs or cavity between roofs are opted for insulation techniques. Fig 4.22 Double roofs

4.4 INFERENCES

Fig 4.23 Bar graph of temperature difference

1. Maximum average temperature diff. (Wall) - 3.6 degrees. 2. Maximum average temperature diff. (Roof) - 4.7 degrees. 3. Maximum average temperature diff. (Both) - 8 degrees. 4. Roof treatment with light, reflective materials should be preferred. Thermal comfort through envelope design

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Thermal analysis

Thermal comfort through envelope design

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Conclusions and Recommendations

4.1 CONCLUSIONS This study analyzed the characteristics of passive and active design techniques introduced to maintain thermal comfort in a energy efficient building. In composite climates, courtyard orientations, width of overhangs, type of shading devices, roof form plays a important role in achieving thermal comfort. Passive design techniques are categorized into building orientation & shape (south orientation, sun shading form, ventilation path, raised roof, and volume to surface ratio), open space (atrium and courtyard), building skin (double skin, translucent skin, louver & sun screen, and closed facade), building planting (green roof, green wall, and water space) in accordance with the design process. The basic concept remains the same in all climates but the size, material, roof form differs. 4.1.1 THESIS It will help in designing of certain aspects for temperature control in thesis. It includes1. Selection of technique for wall construction - Cavity walls should be provided in South and West directions. 2. Different roofing techniques to reduce the internal temperature A courtyard modifies the microclimate of the area. 3. Planning - Washrooms can be provided on the south wall and offices on the north side and can be treated with shading devices.

Fig 5.1 Washroom location

Fig 5.2 Cavity wall locations

Thermal comfort through envelope design

Page | 49

Conclusions and Recommendations

TECHNIQUES

WALL

DIRECTION

ROOF

1. Shading

Louvers

Extended roof

Overhangs

E, W, S

Parapet

Brisle soliel

E, W, S

Space frame truss,

Jaali

All

pergolas, domical roofs

Cavity walls

S, W

Double roofs

Buffer space

E, W, S

Green roofs

Light paints

All

Light grey Tiles

Stone cladding

All

Paints

2. Insulation

3. Reflection

Table 5.1 Techniques

4.2

RECOMMENDATION

4.2.1 FORM AND ORIENTATION Compact form with low S/V ratio is recommended. A square plan with a courtyard would be very effective. A rectangular form with a longer axis along the north-south. East and west orientation should be protected by buffer spaces, shaded walls etc. 4.2.2 SHADING Use fixed horizontal overhangs on south-facing glass. limit the amount of east and west glass (minimize window area) since they are harder to shade. An extended roof can provide shade to the entire north and south wall from the noon soon. Vertical blinds/ louvers can shade the building in North side. 4.2.3 INSULATION Insulation should be placed on the hotter side of the surface. In case of Thermal comfort through envelope design

Page | 50

Conclusions and Recommendations

Summer cooling, it should be outside. 4.2.4EVAPORATIVE COOLING Use of porous materials : Roof materials can cause cooling effect eg: The siliceous shale is able to reduce the roof surface temperature by 8.6 degree. 4.2.5 COOL ROOFS Broken china mosaic, modified bitumen with plastic and a layer of reinforced material, RCC roof topped with elastomeric cool roof coating or simply finished with broken white glazed tiles. Slate and tile products are available with solar-reflective surfaces that offer a wide range of cool colours. Concrete and clay tiles may be obtained in white, increasing the solar reflectance to about 70 percent. 4.2.6 ROOF

Fig 5.4 Temperature difference graph

Double insulation roof, courtyard, parapet should be used to achieve temperature difference of 4.7 Fig 5.3 Roof

degrees.

Fig 5.5 Ecotect Thermal analysis for roof

Thermal comfort through envelope design

Page | 51

Conclusions and Recommendations

4.2.7 WALL

Fig 5.6 Facade

1.Brisle soliel of type 45 degree ( S, W ), Horizontal ( E ), Vertical ( N ) should be used along with cavity walls to achieve difference of 4 degrees. 2. Brisle soliel act as a shading device and cut off the light through its orientation. Fig 5.7 Temperature difference graph

3. Material for brisle soliel is concrete.

Fig 5.8 Ecotect Thermal analysis for shading devices on facade

4.2.8 WALL AND ROOF When both roof and wall techniques for insulation, shading and reflection are applied (above), then average decrease Fig 5.9 Wall and roof

Fig 5.10 Temperature difference graph

is of 8.7 degrees.

Thermal comfort through envelope design

Page | 52

GLOSSARY 1. Thermal comfort - It is the condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation 2. Envelope - It is the physical separator between the conditioned and unconditioned environment of a building including the resistance to air, water, heat, light, and noise transfer. 3. Passive cooling - It focuses on heat gain control and heat dissipation in a building in order to improve the indoor thermal comfort with low or no energy consumption 4. Air conditioning - The process of cooling and dehumidifying indoor air to meet the requirements of thermal comfort or other purposes. A common method of cooling and dehumidifying is by contacting the air to a cold surface such as an evaporator 5. Double-skin facade - It is a system of building consisting of two skins, or facades, placed in such a way that air flows in the intermediate cavity. The ventilation of the cavity can be natural, fan supported or mechanical. 6. Thermal mass - It is the ability of a material to absorb and store heat energy. A lot of heat energy is required to change the temperature of high density materials like concrete, bricks and tiles. 7. Green roof - It is a layer of vegetation planted over a waterproofing system that is installed on top of a flat or slightly–sloped roof. Green roofs are also known as vegetative or eco–roofs. They fall into three main categories— extensive, intensive, and semi–intensive. 8. Roof pond - It is a concept combines the traditional functions of a roof with a means of natural heating and cooling. 9. Cool roof - It is one that has been designed to reflect more sunlight and absorb less heat than a standard roof. 10. Thermal insulation - It is an is an important technology to reduce energy consumption in buildings by preventing heat gain/loss through the building envelope. 11. Double roofs- It is double roof structure separated by air cavity.

xvii

BIBLIOGRAPHY [1] M. Katiyar and S. Agarwal, ―An Overview of Passive Cooling Techniques in Buildings: Design Concepts and Architectural Interventions,‖ Civ. Eng. Archit., vol. 55, no. 1, pp. 84–97, 2012. [2] E. M. Okba, ―Building envelope design as a passive cooling technique,‖ Int. Conf. ―Passive Low Energy Cool. Built Environ., no. May, pp. 467–473, 2005. [3] Y. M. A. Aniza Abdul Aziz, ―Incorporation of innovative passive architectural features in office building design towards achieving operational cost saving-the move to enhance sustainable development. Ar Aniza Abdul Aziz, Yasmin Mohd Adnan,‖ pp. 1–11, 2003. [4] Homeowner Protection Office, ―What is a Building Envelope,‖ p. 2, 2011. [5] A. Ali, ―Passive Cooling and Vernacularism in Mughal Buildings in North India: A Source of Inspiration for Sustainable Development,‖ Int. Trans. J. Eng. Manag. Appl. Sci. Technol., vol. 4, no. 1, pp. 15–27, 2013. [6] M. Rastogi and N. Bansal, ―Pearl academy of fashion  ;An environmentally responsive passive habitat,‖ Proc. - 28th Int. PLEA Conf. Sustain. Archit. + Urban Des. Oppor. Limits Needs - Towar. an Environ. Responsible Archit. PLEA 2012, no. November, pp. 7–12, 2012. [7] E. Conservation and B. Code, ―Design guide,‖ Fire Prev. Fire Eng. Journals, no. MAR., 2007. [8] M. Abuseif and Z. Gou, ―A review of roofing methods: Construction features, heat reduction, payback period and climatic responsiveness,‖ Energies, vol. 11, no. 11, 2018. [9] B. A. Maleki, ―IJTPE Journal SHADING: PASSIVE COOLING AND ENERGY CONSERVATION IN BUILDINGS,‖ Int. J. Int. Organ. TPE, no. December, pp. 72– 79, 2011. [10] J. Lee, K. S. Lee, and J. Lim, ―Passive design techniques applied to green buildings as an aesthetic and spatial design concept,‖ J. Green Build., vol. 10, no. 2, pp. 79–109, 2015. [11] S. Bahga and G. Raheja, ―Delhi from the 1970s to the present,‖ 2019. [12] M. E. S. Soa, ―Case study on Energy Efficient Architecture PEDA office Complex Chandigarh , India,‖ pp. 0–13. xviii

[13] P. By, ―ARCHITECTURE Follows the.‖ [14] C. Chandigarh, ―Case study on Energy Efficient Building.‖ [15] B. Singh, S. Sharma, P. Syal, and & Head, ―NZEB: A Case Study of Indira Paryavaran Bhawan,‖ Int. J. Res. Eng. Appl. Manag., vol. 04, no. 10, pp. 2454– 9150, 2019. [16] M. A. Kamal and S. Arabia, ―Le Corbusier ‘ s Solar Shading Strategy for Tropical Environment  : A Sustainable Approach,‖ Jars, vol. 10, no. 1, pp. 19– 26, 2013. [17] ul Aziz, ―Incorporation of innovative passive architectural features in office building design towards achieving operational cost saving-the move to enhance sustainable development. Ar Aniza Abdul Aziz, Yasmin Mohd Adnan,‖ pp. 1–11, 2003. Webliography https://en.wikipedia.org/wiki/Active_cooling Climatic zones in India – https://www.newlearn.info/packages/clear/thermal/climate/diversity/india/i ndex.html Thermal comfort – https://en.wikipedia.org/wiki/Thermal_comfort Passive featureshttps://nzeb.in/knowledge-centre/passive-design/form-orientation/ Reservoir projecthttps://worldarchitecture.org/architecture-projects/hzfvh/reservoir-projectpages.htm Rat trap bondhttps://architecturelive.in/of-bricks-and-bonds-the-rat-trap-bond/ Shaft box type façadehttp://www.bestfacade.com/textde/0102_fund.htm Dancing louvers- http://inditerrain.indiaartndesign.com/2017/08/thedancing-louvres.html

xix

ANNEXURES List of respondents Ar. Toral Doshi Firm - Sanjay Puri Architects Post - Senior Associate ( 15 years) She has accomplished various small and large scale projects in Rajasthan including Studio 18, 72 screens. 2. Ar. Kartik Khurrana Cofounder - Lines and Thoughts Work experience - 5 years 3. Yash Mamoria Founder - SVE interior, Jaipur Work experience - 10 years Others - Ar. Ishaan Bhatra (Studio Lotus), Ar. Sneha Sharma (Mofa Studio), - Working people of Vidhyut bhavan( Jaipur ), Students of PearAcademy (Delhi) and other people working in offices I - ARCHITECTS Q1. - How do you achieve thermal comfort in your designs? 1. Mechanical i.e., A.C, HVAC 2. Courtyards

3. Wall treatment

4. Roof treatment 5.Other

Most people responded courtyards and mechanical means of cooling Which implies that they seek to incorporate both of them equally. Presence of courtyard decreases the cooling load on the building, hence reduced energy costs. Hence, mixed mode of ventilation is mostly preferred. xx

Q2 - What type of envelope elements do you incorporate in building design to achieve thermal comfort? 1. Window 2. Thick wall with window 3. Cavity wall 4.Double-wall 5.Projections( chajjas, balconies ) 6. R.C.C roof 7. Roof with tiling 8. Roof with paint 9. Roof garden 10. Double roofs

Projections are mostly preferred, which implies shading techniques are preferred over insulation, reflection techniques because they add aesthetic value to the facade as well as cut the glare. Q3 - What is the degree of importance you give to the following while designing in composite climates? 1. Cost

Not important

Less important

Important

Very important

2. Function 3. Aesthetics 4. Labour skills 5. Availability of the material 6. Energy efficiency

xxi

According to this chart, all aspects are important. The highest no of people opted for cost, aesthetics, availability of material i.e, they are the key factors on which designing depends. They might use these to achieve thermal comfort in their designs i.e, through wall and roof . I -SHADING Q4 -What kind of internal and external shading devices you will recommend in terms of simplicity, aesthetics, functionality, the cost for a commercial building in composite climates? 1.Venetian blinds 2. Louvers 3. Roller shades 4. Recessed windows

5. Balconies 6.Awnings 7.Overhangs

8.Fins

9.Brise soleil

10.Other

Most of the responses are for louvers, overhangs, balconies, recessed windows. People opt for external shading devices which may create breathable spaces as in balconies. Overhangs protect from glare, heat of the sun and can be altered in width. Louvers can provide second skin to the structure which may create multipurpose spaces in a building. Q5. What do you prefer for internal/ external shading devices and why? xxii

1. External : overhangs and balconies internal : blinds 2. Pergola /Trellis, They impart a character to the space. 3. Windows 4. Balcony, as it works as both open space and also for shading internal spaces. 5. Play of balconies 6. Plantation, jhaalis , cavity wall, filler slabs 7. My preference will be for those shading devices which are breathable like fabric or any tensile material. Apart from this, large foliage trees are best for natural shade giving. Q6.How do the building envelope impacts the planning of your spaces? 1. To work efficiently we need to make a buffer space between envelope and interior spaces 2. Building envelop is the manifestation of micro and macro climatic factors. Therefore the composition, sequence and hierarchy of spaces is directly or indirectly influenced by the character and form of the exterior envelop of the building. 3. It provide better functioning of the space 4. The massing should done through planning which in return acts as a good building envelope too 5. Keeps them cool and habitable 6. Living spaces and openings preferred in North, east, west orientation 7. Building envelope helps to make spaces more comfortable and esay to maintain.\ Q7. What multiple skin facades do you consider as the most energy-efficient in terms of cost, thermal comfort, sustainability? 1. Box window facades 2. Shaft box type facade 3. Corridor facade 4.Multistorey double skin facade

xxiii

Box window facade got the most responses. Box window facades enable the most individual adaptation of climatic and air conditioning characteristics for each window element. In addition, flexibility is gained on each floor and new room configurations can be established easier. The disadvantages are cleaning effort and cost. Integrating functions like air conditioning, natural lighting or light control into the faรงade increase the complexity and increase the design effort. II-INSULATION Q8.What are the building insulating materials which you consider best for building in Jaipur? 1. Aerated concrete blocks 2.Fibre glass quilts 3. Sheets of aluminium foils 4. Slabs of foamed plastics

Aerated concrete blocks reduces heating and cooling load. Its light weight saves costs and energy, labour expenses. Analysis of response from Spa Mumbai, Sve Interior AAC blocks tends to crack after installation and have demerits as well so bricks can be used along with the insulation material. Q9. What is the form of construction of walls which you use in your practice keeping the composite climate in mind? xxiv

1. Solid wall 2.Cavity wall 3.Rat trap walls

Strength of rat trap walls are more than solid walls and they cost less and better insulation which can also be seen from the responses. Same applies for cavity walls. The cavity can be used for reinforcement purposes as well as insulating material eg: mineral wool can be added. This results in better aesthetics and reduce internal temperatures. Q10. What are the wall materials which you generally prefer for buildings in composite climatic zones? 1. Autoclaved aerated concrete block 2. Fly ash blocks 3.Cellular Light weight concrete blocks 4. Compressed earth blocks 5. Hollow clay blocks 6. Hollow concrete blocks 7. Thermo-insulated blocks 8. Insulated concrete formwork

Hollow clay blocks are light weight, excellent insulation due to hollow profile. Fly ash bricks absorbs less heat, hence provide cooling during summers. Q11. Which are the types of building skin which you will recommend for commercial buildings in composite climate? xxv

1. Textile building skin 2.Metal Wall Panels 3. Steel plates 4.Masonry veneer

5.Cementitious (Fiber-Cement) Siding 6. Precast concrete

Response from SVE interior - Textile building skin is a new concept of light building skins. Their translucencies can vary and they can shade the building. Maximum responses - Masonry veneer can of cavity walls which provide insulation. FIbre cement siding - These are light in weight and can be easily installed and use in the raw form i.e., no finishes are required. They reduce the internal temperatures significantly. III - REFLECTION Q12. What you do in the roof to achieve thermal comfort in composite climates? 1. Roof ponds 2. Paints 3. Tiles 4. Roof gardens 5. Double roofs 6. Sprays

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Greenery covered surfaces were between 15 â&#x20AC;&#x201C; 20 o C lower than exposed concrete surfaces on the roof. They help in temperature control as well as in glare reduction. They can be installed with reflective tiles. They can be integrated with double roof insulation systems in buildings. TOOLS Q13. How important is the knowledge of material processing for analyzing envelope performance? Not important

Less Notimportant important

Important Very important Less important Important

1. Material processing 2. Simulation tools

While doing this study , the knowledge of materials and simulation tools are both important to know the internal temperature. II- WORKING PEOPLE ( OFFICES ) Q1.What is done for external shading? xxvii

1. Projections (Chajja, balcony) 2.Jaali 3.Jharokha 4.None 5.Other

Chajjas, Balconies on the facade implies that there are windows and other openings as well for natural ventilation in the building.

Q2. What is the color tone and nature of the material on the exterior of your office? 1. Light, reflective 2. Light, absorptive 3. Medium, reflective 4. Medium, absorptive 5. Dark, reflective 6. Dark, absorptive Light, reflective and absorptive materials are used in the exterior of office because they reflect light.

Q3. What is the color tone and nature of material of interior of your office? 1. Light, reflective 2. Light, absorptive 3. Medium, reflective 4. Medium, absorptive 5. Dark, reflective 6. Dark, absorptive

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Light, reflective materials are used in the interior of office because they reflect light. Q4.What is the source of natural ventilation in your cabin? 1. Windows 2. Courtyard or chowks 3.None 4.Other

Windows increases ventilation in the building. It creats stack effect, cross ventilation. This helps in reducing the internal temperature. Q5. How can you relate the building through its design? 1. Technological 2. Environmental 3. Socio-cultural 4. Aesthetic

Socio- cultural means when the traditional elements combines with the building envelope and helps people revive their culture. Elements like jaali helps in controlling the indoor temperature.

Q6. What is done on the roof to maintain the temperature? xxix

1. Tiling 2. Pergola 3. Roof garden 4. Roof pond 5. Paint Paint

6.Skylight 7. Other

Tile can help reduce energy costs â&#x20AC;&#x201C; Because of the gap under the tiles, they can help block the sunâ&#x20AC;&#x2DC;s heat from transferring into the attic, thereby reducing your reliance on your air conditioning, lowering your cooling costs significantly. Q7. What is the color of the tiles on the roof? 1. White 2.Red 3.Light grey 4.Beige 5.Brown 6.Other Light colors produce less thermal energy hence, they reflect light and prevents heat to enter the building.

Q8. What material is used on the exterior? 1. Stone 2. Brick 3. Metal 4. Wood 5.Concrete 6.Other

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Bricks can be used in cavity wall, rat trap wall. This helps in insulation of the building. Stone can be used for cladding purposes. Their textures, color helps in maintaining temperature. 3.5.3 INFERENCES BASED ON SURVEY RESULTS

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