Daylight Analysis of Commercial High Rise: A Study of Efficient Daylight by Kinetic Facade by Anuradha Gautam

Daylight Analysis of Commercial High Rise: A Study of Efficient Daylight by Kinetic Facade

DISSERTATION IN ARCHITECTURE 2019-2020

Submitted by:

ANURADHA GAUTAM 9/SSAA/B.Arch./16

Guide: Tanaya Verma, Associate Professor Coordinator: Radha Dayal, Associate Professor

SUSHANT SCHOOL OF ART AND ARCHITECTURE ANSAL UNIVERSITY, GURGAON, INDIA

Anuradha Gautam | 2019

BONAFIDE CERTIFICATE

This Dissertation is submitted by Anuradha Gautam, student of Fourth Year B. Arch. Session 20192020, at Sushant School of Art and Architecture, Gurgaon, as partial requirement for the Five Year B. Arch. Degree course of Ansal University, Gurgaon.

Originality of the information and opinion expressed in the Dissertation are of the author and do not reflect those of the guide, the coordinator or the institution.

Signature of the Student: Roll No.: 9 Name: Anuradha Gautam

Signature of Guide Name: Tanaya Verma Date:

Signature of Coordinator Name: RADHA DAYAL Date:

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ACKNOWLEDGEMENTS

This research paper has been an exceptional experience of learning regarding a subject that has engrossed me for quite a long time. It has been a result of labour, help and support from a large number of people. The success and final outcome of the research required a lot of guidance and assistance from many people and I am extremely fortunate to have got this all along the completion of my research paper. I take this opportunity to express my profound gratitude and deep regards to my guide Ar. Tanaya Verma for her exemplary guidance, monitoring and constant encouragement throughout the course of this research paper. The blessing, help and guidance given by her time to time shall carry- me a long way in the journey of life on which I am about to embark. I am highly obliged to our coordinator Ar. Radha Dayal for giving me an opportunity and allowance to research on the topic of my choice and providing all support and guidance. I would also like to express gratitude to my family and friends who discussed and questioned my ideas throughout the study, encouraged me and helped me move further with it.

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ABSTRACT

In today’s date when focus is on maximizing benefits, efficiency in all operations, the building sector has also started considering the efficiency of the architecture of the building. Hence the introduction of kinetic façades as a climate adaptive facades which have proved their ability of energy efficiency and an improved indoor climate while also achieving optimum human comfort. This study aims to find out the benefits of a kinetic façade for the commercial sector in Gurugram over passive facades. By studying the aspects of kinetic facades and studying existing building with kinetic facades and studying through the lens of light as a major aspect of kinetic façade, inferences will be drawn if there is an exponential impact in daylight in the interior spaces and a suitable kinetic façade will be presented for Gurugram.

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LIST OF TABLES

Table 1: Classification of Climate ……………………………………………………..4 Table 2: Features of Composite Climate ……………………………………………..5 Table 3: Daylight Conditions by Orientation …………………………………………………….10 Table 4: Passive Shading Devices, their Properties and Application …………………..12 Table 5: Vertical Fenestration Assembly U-Factor and SHGC requirements for ECBC Buildings .................……………………………………………………………………………………13 Table 6: Properties of Shading Devices …………………………………………………………….13 Table 7: Glass types and its properties ……………………………………………………………..14 Table 8: Daylight analysis of Al Bahr Towers and Q1 Headquarters …………………..24 Table 9: Analysis of Kinetic Facades all over the world ……………………………………..31

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LIST OF FIGURES

Figure 1: Different Climatic Zones in India ………………………………………………………………4 Figure 2: Circadian (C(λ)) and visual (V(λ)) systems' response to light ……………………8 Figure 3: Difference between Luminance and Illuminance ………………………………………9 Figure 4: Daylight based on Orientation ……………………………………………………………….10 Figure 5: Flow chart for daylight and shading design ……………………………………………16 Figure 6: One Horizon Centre, Daylight Efficiency inside the office space ……………….17 Figure 7: Energy Distribution in a typical office building ………………………………………18 Figure 8: Kinetics definition by three spatial transformation and material distortion ……………………………………………………………………………………………………………19 Figure 9: Kinetic Facades main and sub categories ……………………………………………….20 Figure 10: Kinetic Façade Idea ……………………………………………………………………………21 Figure 11: Double skin façade electricity consumption (KW) versus kinetic façade electricity consumption (KW) …………………………………………………………………..22 Figure 12: Life Cycle of a Kinetic Façade……………………………………………………………..29 Figure 13: Life cycle of a Passive Façade …………………………………………………………….29

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TABLE OF CONTENTS

Bonafide Certificate.......................................................................................................................................i Acknowledgments……………………………………………………………....................................………….ii Abstract ……………...…………………………………......................................................................................iii List of Tables ………………………………….…………………………………....................………………......iv List of Figures ……………………………………………………………………………………………………….v Table of Contents Chapter 1: Introduction..............................................................................................................................1 Chapter 2: Passive Daylight Design Concepts .................................................................................4 2.1 Composite Climate in India-Its characteristics ......................................................4 2.2 Daylight and Visual Comfort Concepts.......................................................................5 2.3 Prevalent Passive Daylight Techniques………………………………………………..10 Chapter 3: An Evolution towards Automated Facades..............................................................17 3.1 Current status of facades in Gurgaon……………………………………………………17 3.2 Need of kinetic facades………………………………………………………………………..18 3.3 Kinetic facades as ultimate facades .....................................................................…...18 Chapter 4: Study of daylight efficiency of kinetic facades …………….....................................23 4.1 Case study: Al Bahr Tower & Q1 Headquarters …...……………………………….24 Chapter 5: Analysis and Conclusion ……….......................................................................................28 Bibliography ……………………………………………………………………………………………………….34 Annex …………………………………………………………………………………………………………………36

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Chapter 1 Introduction A façade is an integral part of a building system. According to Cambridge Dictionary “A façade is the front of a building.” For many years, façades were cladded and made to look decorative, fulfilling the basic requirement of the actual need for a façade i.e. maintain the indoor environment conditions. But in today’s date where the focus has shifted towards energy efficiency, highly controlled indoor environments, the need for climate adaptive façades has increased. According to Cambridge Dictionary adaptive means “having an ability to change to suit different conditions.” Hence in totality, climate adaptive facades are the front of a building which have the ability to change according to different climatic conditions, thus maintaining the indoor climatic condition of the building. A very common example of the concept of climate adaptive facades is the human eye. The pupil inside the eye expands and contracts with respect to changing light intensities around, the eye lashes prevent dust from getting in and the eye lids provide further protection. Similarly is the organisation of a building where the skin of the building is similar to the eye lashes and the eye lid for an eye. But for a long time now, with increasing changes in the environmental conditions people have started using sun glasses or hats in order to provide further protection to their eye in the event of change of weather. Similarly the need of a similar system for a building envelope is required which would adapt itself according to the change in the environmental conditions. The main focus of this study is to analyse climate adaptive façade with respect to daylight in the office spaces. 75 per cent of India’s population consists of the working population thus a large percentage is dependent on the growth of the country. The health of the workers is very important since productivity directly depends on the health of the workers. Since most of the time spent by them is in offices, emphasis should be on improving those spaces to make them more comfortable and healthy thus boosting their performance. One of the most important factor that affects productivity is lighting. Good lighting conditions ensure comfortability of the visual task while poor lighting conditions makes them lousy and has a major impact on their health. The solution to create better working conditions is using daylight to its full potential since it is the most natural form of light and has major health benefits. Since the current passive techniques don’t have an enormous impact in improving daylight conditions an efficient envelope system in the form of kinetic façade as a climate adaptive façade acting as an addition to the passive techniques may create a better performing skin. Though there are a very few traces of intelligent facades in India, there exists no kinetic façade in India. Around the world only limited number of case studies exist for kinetic facades which will be studied for supporting the research. The current study is aimed at comparing the benefits of kinetic facades with respect to passive façade while also devising parameters which govern the selection of an ideal kinetic façade for a particular region by finding one for Gurugram.

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The topic of climate adaptive facades have been studied elaborately on various levels among which some are based on a simulation level, while some have been derived parametrically and are region specific. While some have been studying the efficiency of kinetic façades others have been focused upon trying out different technologies. The dissertation, in short, aims to bring up the new idea of an energy saving kinetic façade design in benefit of the Indian context and side by side testing its feasibility on the basis of analysis of data collected and in the end proposing a suitable kinetic façade for Gurugram. I.

Aim

To study, analyse and compare the performance and importance of using kinetic façades in commercial buildings within the Indian context with respect to daylight.

II.  

Research Question Would the energy savings and the related cost and benefits be more for a kinetic façade in comparison to a passive facade? What are the parameters which govern the selection of an ideal kinetic façade?

Objectives

III.     

IV.

To understand the importance and characteristics of daylight To study the current literature on passive daylight techniques To establish the need of kinetic façade in Gurugram via survey To study present literature on kinetic facades w.r.t daylight To analyse the benefits of kinetic facades and parameters governing its selection

Scope and Limitations

Scope Climate adaptive facades have a wide scope of applicability in all typologies of architectural buildings also having varied health and building environment benefits related to varied problems of each domain. Hence the commercial sector of India has been chosen as the typology for research whose selection criteria will be explained in the research. The scope of the current research is limited to only light as a factor of kinetic façade since the research would be vast if explored on other factors too. Also the studies will be applied on only composite climate in India in Gurugram, Haryana. Limitations An in depth technological study of the topic is not being done since it has more of an engineering background. Also only one factor of climate is being explored since within the given time frame, studying other factors of climate would result in a vast study. Moreover, since there is no existing Kinetic façade building in the Indian context, the study examples will be taken out of the context.

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Methodology:

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Chapter 2 Passive daylight design concepts 2.1 Composite Climate in India-Its Characteristics India experiences variety of climates ranging from warm-humid in south to cold and composite in the north. Figure 1. shows the different climatic zones in India.

Figure 1. Different Climatic Zones in India (Bureau of Indian Standards, 2016)

For the purpose of design of buildings, the country may be divided into the major climatic zones as given inTable1. which also gives the basis of this classification.

Table 1. Classification of Climate (Bureau of Indian Standards, 2016)

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It should be noted that each climatic zone does not have same climate for the whole year; while it has a particular season for more than six months and may experience other seasons for the remaining period. As mentioned in NBC, 2016 “A climatic zone that does not have any season for more than six months may be called as composite zone.” Composite Zone covers the central part of India. Features of a composite climate are as follows: • • • • • •

temperatures in summer and cold in winter, low humidity in summer and high in monsoons, high direct solar radiation in all seasons except monsoons, high diffused radiation, hot winds in summer, cold winds in winter and strong winds in monsoons, And variable landscape and seasonal vegetation.

The various other features of the composite climate zone are shown in the table below:

Table 2. Features of Composite Climate (HPCB, 2012)

2.2 Daylight and Visual Comfort Concepts Daylight has been used as a primary source of light in interiors for as long as man has been living in enclosed spaces and buildings have existed. Daylight is known as a great alternative for artificial lighting during the daytime which reduces energy consumption and also is known to reduce heating or cooling loads thus making it an important parameter for energy efficient designing. “Daylighting describes the controlled use of natural light in and around buildings“(Reinhart, 2014). It is the practice of placing windows, or other transparent media and reflective surfaces so that natural light provides effective internal illumination during the day. Successful daylighting requires design considerations at all stages of the building design process, from site planning to architectural, interior and lighting design (Velux, 2019). The primary source for day lighting is the sun. The light received by the earth from the sun consists of two parts, namely, direct solar illuminance and sky illuminance. For the purposes of day lighting 5

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design direct solar illuminance shall not be considered and only sky illuminance shall be taken as contributing to illumination of the building interiors during the day (Bureau of Indian Standards, 2016).

2.2.1 Benefits of Daylight Human Benefits: Daylight is believed to regulate our sleep and wake timing and increases level of alertness thus resulting in improved performance. Performance and productivity: Bright lighting is usually associated with alertness, and occupants prefer well day lit spaces in comparison to gloomy and dingy spaces. Daylighting aids in improving mood, enhancing morale and reducing fatigue and eyestrain. It has also been recorded that the productivity of employees increased to about 15 percent after moving to a building with better daylight conditions, thus resulting in financial gains.

2.2.2 Visual Comfort Visual comfort is associated with creating adequate lighting levels in a room that it should neither restrain nor impede our ability to see, thus allowing us to perform all our tasks easily. Inadequate lighting can affect our health and well-being resulting in unnecessary eye strain and giving rise to symptoms such as eye irritation, fatigue and headache. Lighting conditions which may cause these symptoms are poor brightness and contrast, high luminance differences and flickering. A good daylighting design ensures glare-free light while a poor daylighting design will provide either inadequate amounts of light leading to an increased use of artificial lighting or large amounts of light, together with glare. A person’s daily life consists of changing visual tasks with requirement of lighting intensity accordingly. Hence the variation of light in the spaces can affect one’s visual comfort and performance. Furthermore, our daily life consists of changing visual tasks, with similarly changing demands on the lighting provided and thus for better visibility, some degree of uniformity of light is desirable. “The sensation of glare can occur when luminance variations exceed 20:1 to 40:1” (Rea, 2000). In the event of glare, the eye adapts to the high level of the glare source, which makes it hard to perceive details in the now too-dark work area. Glare from daylight may be caused by several potential sources such as the sun, bright sky and clouds, and surface reflecting the sun. Mentioned below are the different types of glare •

•

Disability glare – It is the reduction in visibility and visual performance because of the effect of scattered light and occurs when glare sources of high luminance (e.g. sun) are in the field of view. In day lit interiors, it is often found that discomfort glare is reported before disability glare becomes an issue. Discomfort glare – It is defined as an effect which is not necessarily impairing, rather irritating and distracting. The perceived magnitude of discomfort glare is lower than for disability glare. Discomfort glare occurs when there is full visual environment, including windows, reflections or interior surfaces. Headache and fatigue are the forms of side-effects that may be noticed. Reflections or veiling glare – It is caused due to reflections on display screens or other task materials (e.g. paper) which reduces the contrast between background and foreground for 6

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the visual task thus reducing readability. Reflections tend to occur when bright light sources (e.g. windows) are in the reflected field of view of the screen. To reduce the occurrence of glare, shading devices should be employed. ECBC 2017 prescribes the Useful Daylight Index (UDI) for visual comfort. Useful Daylight Index (UDI): “It is defined as the annual occurrence of daylight between 100 lux to 2000 lux on a work plane. The daylight is most useful to occupants, glare free and when available, eliminates the need for artificial lighting.” This can be analysed using simulation software or manually measuring the Daylight Extent Factor (DEF). Apart from improving occupant productivity, it also helps in reduction in electrical load due to lighting energy demand (Bureau of Energy Efficiency, 2009)

2.2.3. Daylight availability The primary target in the daylighting of buildings has generally been to provide adequate light levels in the room and on the work plane, so that daylight is the main, or only, source of light during daytime. There are a lot of metrics that define the availability of light for a particular task or a space while it is important to understand that daylight is variable i.e. it varies with the seasons of the year, the hours of the day and the weather. Hence the metrics for daylighting calculations are more relative than absolute based on the light available inside with respect to the light available outside.

Character of the task and the visual environment where it is performed defines the absolute level of illuminance needed for a particular task. The Chartered Institution of Building Services Engineers, CIBSE (CIBSE, 2006), recommends the following light levels. • • • •

100 lux for interiors with visual task that involves movement and seeing around without any notice to detail. 300 lux for interiors with moderately easy visual tasks. 500 lux for interiors with moderately difficult visual tasks and the requirement of judgement of colours, e.g. general offices, kitchens. 1 000 lux for interiors with very difficult task requiring the perception to small details.

Requirements for daylighting have yet to be defined in terms of specific illuminance levels, but there is enough evidence in literature to indicate that illuminances in the range of 100 to 3 000 lux are likely to result in significant reduction of electric lighting usage (Mardaljevic, 2008).

2.2.4 View Meeting the need for contact with the outside living environment is an important psychological aspect linked to daylighting (Robbins, 1986). It is not enough to provide user satisfaction for views with just the provision of daylight. Windows play an important role of providing contact with the outside environment while also admitting daylight inside, supplying information of orientation, giving experience of weather changes and allowing us to follow the passage of time over the day. Presenting views to the outside ground or sky or landscapes helps to reduce the tiring monotony and the feeling of being closed in. But attention should be given to the size and position of window systems in relation to the eye level of the building occupants. 7

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2.2.6 Spectrum Daylight is known for having the highest levels of light needed to carry out the biological functions compared with other electric light sources. The light which is important for our circadian rhythm (C(λ)) is different from the one required for our visual system (V(λ)). The circadian system (C(λ)) is most affected by the wavelength region 446 to 488 nm, whereas the visual system (V(λ)) is most affected by the wavelength around 555 nm, as shown in figure 2.

Figure 2. Circadian (C(λ)) and visual (V(λ)) systems' response to light (Pechacek et al., 2008).

A narrow wavelength-band of electromagnetic radiation ranging between 380 nm to 780 nm, is perceived by our eyes as light (Szokolay, 2008).

2.2.7 Qualitative aspects of light • • •

Brightness: brightness of an object is judged with respect to the brightness of the surroundings even though to a great extent it depends on the adaption of the eye. Contrast: It is the difference between the brightness of an object and that of its immediate background. Glare: An excessive contrast in light causes glare.

2.2.8 Quantitative aspects of light • • •

Luminous Flux: Amount of light flowing through a space is called Luminous flux. Its unit is Lumens Illuminance: Light falling on a surface is called Illuminance. Its unit is lumens per unit area. (Lux) Luminance: Light reflected from a surface is called luminance (Cd/m2).

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Figure 3. Difference between Luminance and Illuminance (Bureau of Energy Efficiency, 2009)

The best way to ensure a comfortable experience is to create a balance between natural and artificial lighting. The relative amount of sky illuminance is dependent on the position of the sun defined by its altitude, which in turn, varies with the latitude of the locality, the day of the year and the time of the day. The external available horizontal sky illuminance (diffuse illuminance) values which are exceeded for about 90 percent of the daytime working hours may be taken as outdoor design illuminance values for ensuring adequacy of daylighting design. The outdoor design sky illuminance varies for different climatic regions of the country. The recommended design sky illuminance values are 6 800 lux for cold climate, 8 000 lux for composite climate, 9 000 lux for warm humid climate, 9 000 lux for temperate climate and 10 500 lux for hot- dry climate. For integration with the artificial lighting during daytime working hours an increase of 500 lux in the recommended sky design illuminance for daylighting is suggested. The daylight factor is dependent on the sky luminance distribution, which varies with atmospheric conditions. A clear design sky with its non-uniform distribution of luminance is adopted for the purposes of design in this Section. Components of Daylight Factor Daylight factor is the sum of all the daylight reaching on an indoor reference point from the following sources: â&#x20AC;˘ â&#x20AC;˘ â&#x20AC;˘

Direct sky visible from the point, External surfaces reflecting light directly to the point, and Internal surfaces reflecting and inter-reflecting light to the point.

The daylight factors on the horizontal plane only are usually taken, as the working plane in a room is generally horizontal; however, the factors in vertical planes should also be considered when specifying daylighting values for special cases, such as daylighting on classrooms, blackboards, pictures and paintings hung on walls.

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Sky Component (SC) The recommended sky component level as prescribed by NBC should be ensured generally on the working plane at the following positions: • • • •

At a distance of 3 m to 3.75 m from the window along the central line perpendicular to the window, At the centre of the room if more appropriate, and At fixed locations, such as school desks, blackboards and office tables. The daylight area of the prescribed sky component should not normally be less than half the total area of the room.

2.3 Prevalent passive daylighting techniques Every daylight design starts with orienting your building in such a way that one can maximise the benefits of light variable to the direction its coming from. The diagram below shows the quality of light during different seasons and orientations.

Figure 4. Daylight based on Orientation (NZEB, 2019)

Every orientation offers a certain character of light which aids in designing the spaces inside and outside a building. Below is a table mentioning the different daylight characteristics with respect to a particular orientation.

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Table 3. Daylight Conditions by Orientation (Henderson & Anderson, 2011)

After orienting the building to accommodate a desired daylight, the next step should be design the medium of light entrance into the building, i.e. openings. Below are the metrics that define the parameters for design of openings to alter the daylight entering inside a building.

2.3.1. General Principles of Openings to Afford Good Lighting • Generally, while taller openings give greater penetrations, broader openings give better distribution of light. It is preferable that some area of the sky at an altitude of 20° to 25° should light up the working plane. • Broader openings may also be equally or more efficient, provided their sills are raised by 300 mm to 600 mm above the working plane. • For a given penetration, a number of small openings properly positioned along the same, adjacent or opposite walls will give better distribution of illumination than a single large opening. Unilateral lighting from side openings will, in general, be unsatisfactory if the effective width of the room is more than 2 to 2.5 times the distance from the floor to the top of the opening. In such cases provision of light shelves is always advantageous. • Openings on two opposite sides will give greater uniformity of internal daylight illumination, especially when the room is 7 m or more across. They also minimise glare by illuminating the wall surrounding each of the opposing openings. Side openings on one side and clerestory openings on the opposite side may be provided where the situation so requires. • Cross-lighting with openings on adjacent walls tends to increase the diffused lighting within a room. • Openings in deep reveals tend to minimise glare effects. • Light control media, such as translucent glass panes (opal or matt) surfaced by grinding, etching or sandblasting, configurated or corrugated glass, certain types of prismatic glass, tinted glass and glass blasts are often used. They should be provided, either fixed or movable outside or inside, especially in the upper portions of the openings. The chief purpose of such fixtures is to reflect part of the light on to the roof 11

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•

• •

and thereby increase the diffuse lighting within, light up the farther areas in the room and thereby produce a more uniform illumination throughout. They will also prevent the opening causing serious glare discomfort to the occupants but will provide some glare when illuminated by direct sunlight (Bureau of Indian Standards, 2016). For all climatic zones, vertical fenestration compliance requirements for all three incremental energy efficiency levels, i.e. ECBC, ECBC+, and Super ECBC, shall comply with the following: Maximum allowable Window Wall Ratio (WWR) is 40% (applicable to buildings showing compliance using the Prescriptive Method, including Building Envelope Trade-off Method) Assembly U-factor includes both frame and glass area weighted U-factors Assembly SHGC includes both frame and glass area weighted SHGC

Table 4. Passive Shading Devices, their Properties and Application

Vertical fenestration shall comply with the maximum Solar Heat Gain Coefficient (SHGC) and Ufactor requirements of Table 4-10. Vertical fenestration on non-cardinal direction, shall be categorized under a particular cardinal direction if its orientation is within ± 22.5° of that cardinal direction (Bureau of Energy Efficiency, 2009). 12

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Parameter

Composite

Maximum U-Factor (W/m2,K)

3.00

Maximum SHGC Non-North

0.27

Maximum SHGC North for latitude >= 15â&#x20AC;&#x2122; North

0.50

Maximum SHGC North for latitude < 15â&#x20AC;&#x2122; North

0.27

Table 5. Vertical Fenestration Assembly U-Factor and SHGC requirements for ECBC Buildings (Bureau of Energy Efficiency, 2009)

The physical meaning of daylight is radiation in a wavelength range of 0.4-0.7 micron. With its penetration to a building, the radiation causes, in addition to lighting, heating of the interior. Studies have shown that increasing the window area above 1/8 or 1/10 of the area of the floor space does not increase the average intensity of the lighting linearly.* In a room whose walls have an average reflectance factor (0.4) increasing the area of the windows from 1/6 to 1/3 of floor space increased the average intensity of the light by only 60% (Krishan, 2008) The light entering a room is a result of direct (from the sun) and indirect (reflected and diffuse) radiation. In an average room the light will be particularly strong near the windows, where the component of direct light is especially high, and weaker further inside the room, where most of the light is a result of reflection from surfaces within the room itself (Krishan, 2008)

2.3.2. Glass Types and shading devices After the openings have been designed according to the above parameters they are to be closed with glass to maintain the heating and cooling loads inside a building. The type of glass plays a major role in admitting inside daylight in a controlled manner depending on the type of glass used. They can be designed in a manner to reduce or increase the solar gain and the reflectance of a glass. For further manipulation of daylight entering the interior spaces certain shading devices can also be employed to channel daylight in a desired way. The table below mentions the physical properties of the internal shading devices. Penetrating Reflected

Absorbed

Shading

radiation

Factor*

(%)

Venetian Blinds Light, Horizontal

0.55

Semi-dark,

0.64

0.29

Horizontal White, Vertical (closed) 13

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Roller Shutters White, Translucent

0.39

White, Opaque

0.25

Dark, Opaque

0.59

*Shading factor of shading elements combined with 3mm clear glass transmitting 87% of radiation reaching it. Table 6. Properties of Shading Devices (Krishan, 2008)

In the table below are the different types of glasses used for building facades-:

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Table 7. Glass types and its properties

The understanding of above parameters should be done in a methodological order to ensure the efficiency of the whole faรงade system. The flow chart below shows the methodological order of designing for daylighting and shading.

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Start

Form, siting and orientation

Choose fenestration distribution

Building Function

Establish target daylight factor

Select suitable shading devices

Adjust design

Evaluate diffuse transmission factor

Make proposal for opening area check DF by calculation

Adjust design

Check performance of shading devices Consider other constraints e.g. Glare, aesthetics etc.

Figure 5. Flow chart for daylight and shading design (Krishan, 2008)

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Chapter 3 An evolution towards kinetic facades 3.1. Current Status of façades in Gurgaon Gurgaon has become a hub for big companies setting up their office with huge buildings having seamless glass facades. After conducting a survey in a few office buildings of Gurgaon it was noticed that most people are unsatisfied with the façade because of the daylight quality it offers. The façade systems render almost useless in altering the daylight to suit the users. Not only that but the users

Figure 6. One Horizon Centre, Daylight Efficiency inside the office space

The above picture is from AMEX, One horizon Centre, LEED gold certified building. There it was analysed that even after having a double skin façade, people had to shut their blinds throughout the day due to glare from the sun. Even during the daytime the artificial lighting is used to the maximum. Hence it can be seen that passive designing is not the ultimate solution to get efficient daylight into the spaces. Thus, it shows that there is a need of a better façade system even though the passive techniques have been applied.

3.1.1. Energy Consumption The inefficiency of the façade in controlling the daylight that enters the interior spaces has led to an increased use of artificial light, while the daylight is obstructed by the use of shades and blinds. Artificial lighting amounts up to 30 per cent of the total cost of running the building. Since most office buildings run only during the daytime this cost can be hugely reduced by admitting maximum daylight without causing any discomfort to the occupants. 17

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Figure 7. Energy Distribution in a typical office building (Bureau of Energy Efficiency, 2009)

But there are other arguments that say with the develpement of technology, the lighting fixtures now consume lesser energy to operate. But even after this development it still accounts for a major chunk of a building’s energy consumption since the emmitance of lighting fixtures also amounts to a certain heating and cooling load. Not only is daylight an energy efficient alternative but also aids in user’s health.

3.2. Need of Kinetic Facades Architecture must change and cannot continue to ignore climate change and the destruction of our biosphere. An effective ecological design is becoming an increasingly complex task, due to a growing demand to satisfy more ambitious environmental, societal and economic performance requirements. The building needs to be in closer relation to the climatic context, and as the building envelope is the border between the surrounding climate and the interior, the envelope design is becoming a crucial parameter in sustainable and energy efficient building design.

3.3. Kinetic Façade as an ultimate automated Façade 3.3.1. Functions of a facade It is evident that in order to provide optimal comfort to the users one must cater for every physical aspect of the building which seems rather difficult since one aspect might contradict one another e.g. requirement for thermal insulation differ from those for acoustic quality which also differ from the requirement of daylight admittance. However, there are some very basic functions that every building skin needs to incorporate such as providing shelter from wind, thermal insulation, waterproof and being structurally sound. While considering for office environment, there are a set of additional façade requirements which are required to be formulated in order for the function to be performed efficiently by the users such as providing an optimal work environment by making it thermally comfortable, creating agreeable lighting levels and acoustically comfortable environment while also ensuring a healthy indoor air quality.

3.3.2 Classification of Kinetics Zuk and Clark in 1970 clarified the need of kinetic Architecture “we must involve an architecture that will adapt to continuous and accelerating change” they considered kinetics application in architecture as solution for managing with continuous change (Salter, 2010). Kinetic architecture is also illustrated as building elements that have variable geometry or location (Fox & Yeh, 2000). Kinetics movement can be defined by three spatial transformations (translation, rotation, scaling) or through movement by material distortion as shown in the figure below. 18

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Figure 8. Kinetics definition by three spatial transformation and material distortion (Moloney, 2011)

Translation is the movement of an element on a regular planar path while rotation is the movement of an element around an axis and scaling is the change in the mass of an object by expansion or contraction. Other complex movement types such as twist or roll are a combination between these three basic movements. The fourth type of material distortion depends on material properties as elasticity of materials. This definition helps in differentiation between other types of facades that can be mixed with kinetic facades as media façade that depends on light and its effects and projection on screen (Moloney, 2011).

3.3.3 What are Kinetic Facades? A façade acts as a direct link between the indoor and outdoor spaces with is main function being the protection of indoor spaces from the changing outside environment. The continuous change in the outdoor environment affects human comfort, hence the need of the hour is to make façades environmentally responsive to the outdoor conditions. The use of actuators as an element of responsive architecture is applied, which is the direct application of kinetic facades. Kinetic facades is the physical movement of façade to respond to the surrounding changing conditions (Mejia, 2010).

Classification of Kinetic Facades In 2011, Moloney introduced his classification for Responsive Kinetic Facades types, which was based on classifying the façades according to the type of geometric transformations occurring in the building façade (Moloney, 2011). Since then, researchers followed Moloney in his classification. However, this classification handles the kinetic façades from a geometrical perspective only (façade components motion). Moreover, this categorization was somehow broad; as these transformations can comprise other classifications underneath. The two broad main factors:  

Façade configuration Façade function

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Figure 9. Kinetic Facades main and sub categories (Waseef & Mowafy, 2017)

3.3.4 Kinetic Façade as an Intelligent Façade In nature the organisms adapt to the changing environments to survive for example some plants such as snow buttercup monitor the direction of sunlight to gain the most of it. Also, King Protea plant opens and closes according to the quantity of sunlight it needs. This reveals the concept of responsive systems according to environmental conditions (Henriques et al., 2012). It is necessary to understand that the building facades need to be adaptable to the environmental conditions for an efficient daylighting system. Using the old fashioned louvers and overhangs might help in solar shading but they don’t ensure prevention from glare which would mean that another system would be required along with the pre-existing façade to prevent it. But with the use of today’s technology, maximum daylight penetration can be ensured with the use of automated movable system that can be used to help control daylight and thermal loads in office buildings. The term intelligent building envelope has become a common denominator for a certain type of built form that uses artificial intelligence to provide the indoor environment with dynamic heating, cooling, lighting and air supply, aiming to procure optimal balance between occupant comfort and energy use (Upadhyay, 2017). Building envelopes should potentially be able to give substantial reductions in energy use and peak power demand. An intelligent building envelope’s contribution to an indoor environment supportive of human needs can be analysed in five steps (Upadhyay, 2017): • • • • •

Sensory perception Mental model Assessment of information and feedback Strategic thinking Implementation

An intelligent building envelope may be expected to fulfil three objectives: to cope with a variable environment, to cope with a conflictive environment, and to cope with human behaviour (Upadhyay, 2017). An intelligent building envelope is supposed solve problems that occur in its interaction with the environment which may sometimes be conflicting. The envelope thus need to decide on a prevalent set of priorities, and find an optimal solution to all of the tasks.

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Better performance in buildings with intelligent features can be achieved by the following processes put forward by Krishan Upadhyay: • • •

Creating a relationship between occupant behaviour and indoor space conditions. Creating provisions of automatic adjustments with respect to changing environment conditions and occupant requirements. Generating cost-effective modifications which will be based on changes in tasks and users behaviour.

Components of kinetic façade Responsive Kinetic Façade depends on high-tech technologies and techniques. It consists of four main components (Maia and Meyboom, 2015), refer to figure 7: • • • •

Sensors that read the environmental variables. A Logical unit processes collected data and form a response. Actuators that respond to the environmental conditions. Wired/wireless communication (management system) that transfers information through all components.

Figure 10. Kinetic Façade Idea (Waseef & Mowafy, 2017)

3.3.5 Why invest in facades? India is the world’s fourth largest energy consumer (EIA, 2013) and fifth largest source of greenhouse gas emissions (GOI, 2010). With the building sector contributing 35% of the total electricity consumption (Rawal et al, 2012), and a projected five-fold growth in the constructed area anticipated by 2030 - from a 21 billion square feet in 2005 to 104 billion square feet, building energy efficiency plays a major role in managing energy use in India (Seth, 2010). The fast development in Indian development part, the national government's endeavours to improve vitality productivity in structures depends on noteworthy decreases in cooling, ventilation, lighting and attachment loads. Building façade plan and designing is basic to: cooling loads through sun powered warmth control; to regular ventilation and late evening cooling; to viable day lighting; and even free passive solar heating in cooler climates. High performance, climate responsive facades are known to significantly reduce both annual and peak electricity demand, and ensure “resiliency” in the face of power outages. Equally critical, high performance facades are critical to occupant health and productivity.

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Figure 11. Double skin faรงade electricity consumption (KW) versus kinetic faรงade electricity consumption (KW) (Bacha & Bourbia, 2016)

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Chapter 4 Study of daylight efficiency of kinetic facades

Kinetic façade being a very complex system of façade designing needs scrutiny at every stage of its design. Just like while designing passive facades one needs to follow certain steps to achieve the final design as mentioned in the previous chapter, the same has to be applied while designing kinetic facades. This chapter deals with the detailed study of kinetic facades based on the following parameters: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.

Climate type: The type of climate pertaining to the region Building Orientation: The building orientation to analyse passive design methods Adaptive Element: An automated kinetic unit which is repeated all throughout the facade Aim of the adaptive element: To understand the main purpose of the facade Working principle: The theory regarding the functioning of the facade Material: To understand the thermal efficiency of the facade Shading Principle: To understand the concept of shading evolved Distance from façade: To understand the incorporation of services Technology used: Technology deployed to make the façade function Illuminance achieved: This will give the daylight efficiency of the facade Embodied Energy: The sum of all the energy required in the movement of the facade, considered as if that energy was incorporated or 'embodied' in the product itself. Power savings: This will help in identifying the quantative benefits Durability: Estimating the life of the façade Visibility: It identifies if the façade provide enough views to the outdoor environment Artificial Lighting: The mechanism of artificial lighting used Other benefits: It specifies the other benefits the façade may provide Cost: To give an estimate of the cost of the entire facade

The selection of building was done on the criteria of choosing the region with a similar climate i.e. one which has hot summers and cold winters and the building to be a commercial building. Hence with the availability of limited kinetic façade and the data in a similar kind of weather, the study will be conducted on Al bahr tower in Abu dhabi and Q1 headquarters in Germany.

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Table 8. Daylight analysis of Al Bahr Towers and Q1 Headquarters

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Chapter 5 Analysis and Conclusion Gurugram is a fast developing city with the emergence of the offices of big companies and MNC’s. Where the design of the building is focused to make a statement, the functioning of them might not be the best to be boasted about. With the lack of human comfort inside these huge glass buildings, they fail to make a statement for its users which are the main identity of a building’s existence. In order to understand the current situation of the daylight entering these spaces, a survey was conducted wherein participants from different offices were asked about the efficiency of their workspaces with respect to daylight and the visual comfort that follows. The target audience for the survey were people working in office buildings in Gurugram having a complete glass façade. The survey was divided in categories on the basis of placement of the work station of the user which was as follows-: 1. Close to the window 2. Middle 3. Away from the window Out of 10 people 5 people worked close to the window while 3 in the middle and 2 away from the window. The questions being the same for people sitting in the middle or away from the window, following are the results of the survey: Close to the window: 5 out of 5 people reported glare problems close to the window while in all of the 5 responses blinds were used to cut off glare, thus restricting them views to the outside. 3 out of 5 people preferred working under daylight and thus preferred an external automatic system of shading. While the other 2 did not prefer working under daylight. Middle: 3 out of 3 people used mostly artificial light while 2 out 3 people used it because of the inefficiency of daylight reaching their work stations. 1 out 3 people did not prefer working with daylight. 2 out of 3 people wanted an automated façade to bring the light deep into their space. Away from the window: 2 out of 2 people use mostly artificial light for their office tasks and thus require daylight. 2 out of 2 people prefer an automated façade system. Hence from the responses it can be concluded that current facades of office building are not providing comfortable indoor environment to its users when it comes to daylight. Thus the need of an automated façade arises. While kinetic facades could be a better option for day lighting and benefits that follow, there are certain drawbacks that should be considered while deciding to opt for one. The two diagrams below enlist the various phases of adopting kinetic and passive façade for a building.

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Figure 12. Life Cycle of a Kinetic Facade

Figure 13. Life cycle of a Passive Facade

In the above diagrams we can see that while the initial cost of setting up a kinetic façade is greater than a passive façade, the benefits are more in a kinetic façade. Not only does it increases the level of human comfort and energy savings but later after its service life it can be renewed and changed according to the technology advancements while the same would be hard to incorporate in a building with a passive façade. Not only do kinetic façade has their own embodied energy but when combined with a renewable energy source the energy savings increase. An equation below presents the benefits of the combination of the two. Considering, x = amount of energy is being used to run the kinetic façade, a = energy produced by renewable energy source And –b = energy reduction because of kinetic façade deployment. Then, the equation derived will be -: X = a + (-b); This formula would therefore give the energy saving benefits from the deployment of a kinetic façade and a connected renewable energy source. While another formula could be derived to analyse the case where the renewal cost of kinetic façade is compared to the energy saved by the façade all along its lifetime. Considering, x = cost of energy saved throughout the working of the façade and y = the cost of renewal of the façade after it has crossed its service life, The equation will be as follows-: If, x = y, then the façade is neither providing any benefits nor has any negative results, If x > y, then the façade is giving positive benefits in the form of cost savings w.r.t. energy consumption

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If x < y, then the façade deployment is a liability rather than an asset in energy consumption Hence before opting for a kinetic façade, the above formula should be used to know if the façade is going to give positive or negative benefits throughout. Its life. With the above analysis one can conclude if the benefits of a kinetic façade are greater than if opted for a passive façade. It should be realised that not only does the cost define the use of a kinetic façade but the region also affects the selection of a kinetic façade. A study has been conducted below to select the ideal kinetic façade for office buildings in Gurugram, India which has a composite climate, which will thus give us the connection between the region and kinetic façade selection. The analysis will be done by comparing different kinetic facades all around the world and comparing them on the parameters listed below-: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

Climate: The type of climate of the region Orientation of the façade: To analyse the passive technique incorporated Movement: To analyse the workability of the facade Daylight Efficiency: To make sure the kinetic façade is fulfilling its purpose Shading and Glare control: It is an important aspect under visual comfort Material Thermal Property: To analyse the physical property of the material and its availability Visibility: To see if there are views through the facade Durability: To ensure if the façade benefits are worth the investment Cost: The cost of setting up of the facade User control: It deals with the ease of interaction of the users with the facade Energy Savings: The quantitative benefits of the facade

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On the basis of energy savings it can be seen that Al bahr tower, RMIT design hub, Q1 headquarters, GSW Headquarters and Carabanchel Social Housing have the most energy savings. While it can be seen that Q1 headquarters has the most daylight efficiency and visibility, when it comes to material properties AL bahr tower and Carabanchel social housing having similar shading and glare control and a good amount of daylight efficiency , have better material thermal properties. On the basis of best material properties the best kinetic façade for a composite climate is Carabanchel social housing’s bamboo façade. Not only is bamboo easily available as compared to PTFE membrane of al bahr towers, it has much better thermal properties. When it comes to views al bahr tower has better view creation. But when it comes to the aim of the study which not only includes daylight efficiency but also energy savings, Carabanchel social housing’s façade stands out.

CONCLUSION Building being a bear shell has the ability to be enveloped by various possibilities. The advancement of technology has led to variations in building envelope design which might be aesthetic driven or with a focus towards energy saving. Kinetic façade not only aids in energy savings but gives life to the once static building shell. From the survey it was seen that the current working population of Gurugram is not satisfied with the current façade system and that there is a need for a better façade system in Gurugram which is able to adapt to the needs of the users. In order to find a better façade the research paper dealt with studying kinetic façade as the ultimate automated façade for Gurgram. It was realised that in order to build the perfect kinetic façade for a building various factors like- Geographical location, technology available, material properties etc. had to be studied deeply with respect to the façade. The result was that kinetic facades do have high initial cost, but by implementing them in the right manner, the owner can reap tons of benefits from it too and that a kinetic façade would not function in the right way if passive techniques were not followed. Hence it should be realised that no building can function properly with respect to daylight until and unless it adheres to the passive techniques first. The question arises, what happens when the technology deployed in the kinetic façade becomes obsolete with the emergence of a much more sophisticated technology? Kinetic facades being an add on to the building shell can be replaced as and when required, which is the biggest benefit of it. So when the technology advances, so does the building, without causing any damage to the main structure. Are kinetic facades the only solutions or there could be other ways to achieve optimum daylight? How, the addition of renewable energy source in the building can make the kinetic façade more efficient? Can the user interaction be increased to make the facades more user friendly?

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BIBLIOGRAPHY • •

•

• • • • • • • • • • •

• • •

Aelenei, L., 2018. Case Studies – Adaptive Facade Network. TU Delft Open. Ahmad, Mohammad & Tiwari, G. (2008). Estimation of Hourly Global Solar Radiation for Composite Climate. The Open Environmental Journal. 2. 34-38. 10.2174/1874233500802010034. Ayyappan, K.L., 2018. A REVIEW ON THE APPLICATION OF KINETIC ARCHITECTURE IN BUILDING FACADES. International Research Journal of Engineering and Technology 05. Balascakova, P., 2016. Energy Design Vol. IV/I. Adaptive Facade Systems”. Institute of Buildings and Energy (IGE), Vol. IV/I Ben Bacha, Cherif & Bourbia, Fatiha. (2016). Effect of kinetic facades on energy efficiency in office buildings - hot dry climates. Boyce, P., Hunter, C. and Howlett, O. (2003) The Benefits of Daylight through Windows, Lighting Research Center, Rensselaer Polytechnic Institute. Bureau of Indian standards, 2016. National Building Code, 2016th ed. Edwards, L., Torcellini, P. (2002) A Literature Review of the Effects of Natural Light on Building Occupants, National Renewable Energy Laboratory,U.S. Department of Energy. EIA - Energy Information Administration. 2013. India – Country Analysis Brief, http://www.eia.gov/countries/analysisbriefs/India/india.pdf El-Dabaa, Rana. (2016). The Use of Kinetic Facades in Enhancing Daylight Performance for Office Buildings. 10.13140/RG.2.2.36431.59041. Energy Conservation Building Code (ECBC), Bureau of Energy Efficiency, 2008, “New Delhi. India Foged, Isak & Kirkegaard, Poul. (2011). Development and Evaluation of a Responsive Building Envelope. Foged, Isak & Kirkegaard, Poul. (2011). Development and Evaluation of a Responsive Building Envelope. Fox, M. A., & Yeh, B. P. (2000). Intelligent Kinetic Systems in Architecture. In P. Nixon, G. Lacey, & S. Dobson (Eds.), Managing Interactions in Smart Environments (pp. 91– 103). Springer London. GOI – Ministry of Environment and Forests. 2010. India: Greenhouse Gas Emissions 2007 Henderson, B., & Anderson, L. (2011). The Lighting Handbook 10thEdition. Illumination Engineering Society. Kensek, Karen & Hansanuwat, Ryan. (2011). Environment Control Systems for Sustainable Design: A Methodology for Testing, Simulating and Comparing Kinetic Facade Systems. Journal of Creative Sustainable Architecture & Built Environment. 1. Koenigsberger, O.H., 2013. Manual of Tropical Housing and Building. Universities Press (India) Private Limited, Hyderabad, India. Krishan, A., 2001. Climate Responsive Architecture: A Design Handbook for Energy Efficient Buildings. Tata McGraw-Hill Education. Loonen, Roel & Trcka, Marija & Hensen, Jan. (2011). Exploring the potential of climate adaptive building shells. Proceedings of Building Simulation 2011: 12th Conference of International Building Performance Simulation Association. 2148-2155.

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MAIA, S., MEYBOOM A., 2015. Interrogating Interactive and Responsive Architecture: The Quest of a Technological Solution Looking for an Architectural Problem. In proceedings of the 16th International Conference on Computer-Aided Architectural Design Futures, São Paulo, Brazil, 8-10 July 2015, 93-112. Mardaljevic, J. (2012) Daylight, Indoor Illumination and Human Behavior in Encyclopedia of Sustainability Science and Technology Springer-Verlag New York Inc, New York. ISBN 978-0-387-89469-0, pp 2804-2846 MOLONEY, J., 2011. Designing kinetics for architectural facades: state change. USA: Taylor & Francis, 7-8. Mounir, Yasmin. (2017). Modern Mashrabiyas with High-tech Daylight Responsive Systems. The Academic Research Community publication. 1. 10.21625/archive.v1i1.113. NZEB. [ONLINE] Available at: https://nzeb.in/blog/. [Accessed: 3/11/19] Pechacek, C. S., Andersen, M., Lockley, S. W. (2008) Preliminary method for prospective analysis of the circadian efficacy of (day) light with applications to healthcare architecture. Leukos, 5(1), 1-26) Rea, M.S. (2000) The IESNA Lighting Handbook: Reference and application, New York: Illuminating Engineering Society of North America. Reinhart, C. (2014) Daylight Handbook I Robbins, C. L. (1986) Daylighting Design and Analysis, New York: Van No strand Reinhold Company. Salter, C. (2010). Entangled: Technology and the Transformation of Performance. Cambridge, Mass: MIT Press. Sharaidin, K., 2014. Kinetic facades: towards design for environmental performance. RMIT University, Australia. TERI, HPCB. [ONLINE] Available at: http://high-performancebuildings.org/climatezone.php. [Accessed: 3/11/19] Upadhyay, K.; Ansari, A.A. Intelligent and Adaptive Facade System—The Impact on the Performance and Energy Efficiency of Buildings. J. Civil Eng. Environ. Technol. 2017 Velux.[ONLINNE] Available at: https://www.velux.com/deic/daylight/daylightcalculations-and-measurements. [Accessed: 3/11/19] Waseef, Ahmed & El-Mowafy, Basma. (2017). TOWARDS A NEW CLASSIFICATION FOR RESPONSIVE KINETIC FACADES. Zuk, W. and R. Clark, Kinetic Architecture. 1970: Van Nostrand Reinhold, New York.

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ANNEX Below are the questions used for the survey. General Questions: Q1. E-mail address Q2. Name Q3. Office name and Address Q4. What are your work timings? a) 9am â&#x20AC;&#x201C; 5pm

b) 10am- 6pm

c) Mention any other

Q5. What is the location of your work desk in your office? a) Close to the window b) Middle

c) Away from the window

Close to the window: Q1. Is the intensity of Daylight very harsh on your work desk? a) Yes

b) No

Q2. Do you use any internal shading system e.g. Blinds? a) Yes

b) No

Q3. Can you see the views outside after applying the shading system? a) Yes

b) No

Q4. Is the internal shading system of your office efficient with respect to allowing proper intensity of light to work in? a) Yes

b) No

Q5. Do you use more of artificial light or day light for work? a) Artificial Light

b) Daylight

Q6. Is the daylight consistent to work in throughout the day on your work desk?

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a) Yes

b) No

Q7. Would you prefer working more under daylight? a) Yes

b) No

Q8. Would you prefer an external automatic system of shading to alter the intensity of daylight on your work desk with no obstruction of views? a) Yes

b) No

Q9. Would you also like the automated system to also be adjustable manually when required? a) Yes

b) No

Middle and away from the window: Q1. Do you use more of artificial light or day light on your work station? a) Artificial Light

b) Daylight

Q2. Do you use artificial light because of the inefficiency of daylight on your work desk? a) Yes

b) No

Q3. Would you prefer working under constant daylight intensity? a) Yes

b) No

Q4. Would you like a special faรงade system to transmit more light inside? a) Yes

b) No

Q5. Would you want that system to be automated? a) Yes

b) No

Q6. Is the daylight consistent throughout the day on your work desk? a) Yes

b) No

Q7. Would you like a special faรงade system to keep the daylight intensity constant? a) Yes

b) No

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Q8. Would you prefer an external automatic system of shading to alter the intensity of daylight on your work desk with no obstruction of views? a) Yes

b) No

Q9. Would you also like the automated system to also be adjustable manually when required? a) Yes

b) No