Natural Lighting and Shading

8/10/2019 Natural Lighting and Shading

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DISSERTATION

NATURAL LIGHTING and SHADING

(EXCLUDING FENESTRATIONS)

Submi tted by:

SHAIK MAHAMMED AZARUDDIN

Department of Architecture and Planning MANIT, BHOPAL

MAULANA AZAD NATIONAL INSTITUTE OF TECHNOLOGY,

BHOPAL

MAY 2014


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ACKNOWLEDGEMENT

I would like to gratefully and sincerely thank Dr. Nakul Dhagat for his guidance,

understanding, patience, and most importantly, his friendship during my dissertation research

study. He encouraged me to grow as an instructor and an independent thinker. I am not sure

many graduate students are given the opportunity to develop their own individuality and self-

sufficiency by being allowed to work with such independence.

The writing of this dissertation has been one of the most significant academic

challenges I have ever taken. Though the following dissertation is an individual work, I could

never have reached the heights or explored the depths without the help of books published by

various authors, the e-books available on the internet, the research papers published byvarious authors and the various organizations and websites providing information related to

my dissertation topic. This work is an outcome of an unparalleled infrastructural support that

I have received from Maulana Azad National Institute of Technology.

My very special thanks to my family members whom I owe everything I am today,

Thank you for everything.

Last but not the least; I would like to thank my friends who also became the backbone

of my support while researching on my dissertation for nights after nights restlessly.

Shaik Mahammed Azaruddin


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Table of Contents

Table of figures ................................................................................................................................... 5

Chapter-1. ............................................................................................................................................... 7

1.1 Introduction ............................................................................................................................ 7

1.1.1 Background ..................................................................................................................... 7

1.1.2 Justification ..................................................................................................................... 7

1.1.3 Need ................................................................................................................................ 8

1.1.4 Applicability ..................................................................................................................... 8

1.2 Aim .......................................................................................................................................... 9

1.3 Objectives................................................................................................................................ 9

1.4 Scope of work.......................................................................................................................... 9

1.5 Methodology ......................................................................................................................... 10

Chapter-2. Understanding Natural light ......................................................................................... 12

2.1 Definition of Natural Light .................................................................................................... 12

2.2 Need for Natural Light .......................................................................................................... 12

2.3 Evolution of Means of Providing Natural Light in Buildings ................................................. 13

2.3.1 Early History .................................................................................................................. 13

2.3.2 History of English Natural Light ..................................................................................... 142.3.3 Dutch, Venetian, and Japanese Design Developments................................................. 20

2.3.4 History of American Natural Lighting ............................................................................ 21

2.4 Characteristics of Natural Light ............................................................................................. 23

2.4.1 Defining the parts of Natural Light - Sunlight and Skylight ........................................... 23

2.4.2 Dynamics of Natural Light ............................................................................................. 24

2.5 Environmental Factors Affecting Natural Light ..................................................................... 24

2.5.1 Sunlight Effect ............................................................................................................... 24

2.5.2 Change and Variety ....................................................................................................... 26

2.6 Effect of Building Orientation on Lighting............................................................................. 27

2.6.1 Introduction .................................................................................................................. 27

2.6.2 Significance ................................................................................................................... 28

2.6.3 Design Procedure: ......................................................................................................... 28

2.7 Summary ............................................................................................................................... 29

Chapter-3. Understanding Building Mass and Punctures ............................................................... 30

3.1 Defining Building Mass .......................................................................................................... 30


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3.2 Additions and subtractions in building mass ........................................................................ 31

3.2.1 Subtractive Forms ......................................................................................................... 31

3.2.2 Additive Forms .............................................................................................................. 33

3.3 Defining Punctures in Building Mass..................................................................................... 35

3.4 Categorization of Punctures in a Building ............................................................................. 36

3.4.1 Within planes ................................................................................................................ 36

3.4.2 At corners ...................................................................................................................... 37

3.4.3 Between Planes ............................................................................................................. 39

3.5 Summary ............................................................................................................................... 41

Chapter-4. Effect of Building Mass and Punctures on Lighting ....................................................... 42

4.1 Study of Lighting in Different Styles of World Architecture through History ....................... 42

4.1.1 Egypt ............................................................................................................................. 42

4.1.2 Greece ........................................................................................................................... 42

4.1.3 Rome ............................................................................................................................. 43

4.1.4 Early Christian ............................................................................................................... 43

4.1.5 Byzantine ....................................................................................................................... 44

4.1.6 Gothic ............................................................................................................................ 44

4.1.7 Renaissance ................................................................................................................... 44

4.1.8 Baroque ......................................................................................................................... 45

4.2 Case Studies of Todays Existing Buildings ............................................................................ 45

4.2.1 Le Corbusier .................................................................................................................. 46

4.2.2 Louis I. Kahn .................................................................................................................. 48

4.2.3 Tadao Ando ................................................................................................................... 49

4.3 Summary ............................................................................................................................... 50

Chapter-5. Observations and Discussions ....................................................................................... 51

5.1 Conclusions from the Case Studies ....................................................................................... 515.2 Observations about the Void Massing Determinants ........................................................... 56

5.3 Conclusions about Void Building Form ................................................................................. 57

5.4 Observations of Void Buildings from Existing City Grids ....................................................... 58

References ............................................................................................................................................ 61


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Table of figures

FIGURE 2-1 DOORWAYS - NATURAL LIGHTING FROM ONE SIDE OF A ROOM .............................................. 14

FIGURE 2-2 INTERIOR VIEW - NORMAN WINDOW ....................................................................................... 15 FIGURE 2-3 THESE SMALL ; DEEPLY SPLAYED WINDOWS ON L ARSEN H ALL AT H ARVARD ARE REMINISCENTOF N ORMAN WINDOWS , ALTHOUGH THERE IS PRESUMABLY LESS FEAR OF ATTACK .......................... 15

FIGURE 2-4 ( LEFT ) T HE T OWER OF LONDON ' S INTERIOR DEMONSTRATES THE " TONAL GRADING " PRODUCED BY A SUCCESSION OF VAULTS . (R IGHT ) T HIS BUILDING AT Y ALE , BUILT IN THE 1930' S , HAS REFERENCES TO OLD E NGLISH WINDOW DESIGN . ..................................................................... 17

FIGURE 2-5 A GOTHIC -STYLE WINDOW AT Y ALE SHOWS EXTERNAL SPLAYING OF STONE ELEMENTS , WHICH INCREASES INTERIOR ILLUMINATION ............................................................................................... 18

FIGURE 2-6 ( LEFT ) T HESE SHUTTERS FOLD BACK INTO THE REVEALS OF THE WINDOW . T HEY ARE ALSO ADJUSTABLE LIKE VENETIAN BLINDS . ( RIGHT ) BOTH TYPES OF BAYS ARE SEEN ON THIS FACADE ON BOSTON ' S B EACON H ILL. ................................................................................................................ 19

FIGURE 2-7 DUTCH W INDOWS - E LEVATION ( LEFT ) ................................................................................ 20 FIGURE 2-8 ALTHOUGH THESE ARE NOT THE ORIGINAL DIAMOND -SHAPED LIGHTS , THEY REFER BACK TO

EARLY 17 TH CENTURY WINDOWS . .................................................................................................... 22 FIGURE 2-9 LIGHTING THROUGH PALLADIAN WINDOWS .......................................................................... 22 FIGURE 2-10 BEAMS OF DIRECT SUNLIGHT CAN BE MAGICAL .................................................................. 23 FIGURE 2-11 THE SUN IN THE NORTHERN HEMISPHERE ........................................................................... 26 FIGURE 2-12 WELL ORIENTED BUILDINGS ............................................................................................... 28 FIGURE 3-1 BUILDINGS OF DIFFERENT SIZES ......................................................................................... 30 FIGURE 3-2 THE SPHERE , T HE PYRAMID AND THE CUBOID RETAINS THEIR IDENTITY EVEN IF THE BASE

PORTION OF THE SOLIDS IS REMOVED . ............................................................................................ 32 FIGURE 3-3 A PORTION IS SUBTRACTED FROM EACH OF THE CUBOIDAL FORM AT THEIR PROFILE EDGES . 32 FIGURE 3-4 THE IMAGINARY LINES FORMING THE ORIGINAL PROFILE ..................................................... 32 FIGURE 3-5 H OUSE AT S TABIO , S WITZERLAND , 1981, M ARIO BOTTA ..................................................... 33 FIGURE 3-6 PHYSICAL ATTACHING OF TWO CUBES IN PLAN ..................................................................... 33 FIGURE 3-7 TWO FORMS COMBINE TO FORM A MIXED GEOMETRY ........................................................... 33 FIGURE 3-8 TWO CUBES ATTACHED AT ONE OF THEIR CORNICES ............................................................. 34 FIGURE 3-9 TWO SOLIDS ATTACHED BY OVERLAPPING FACES .................................................................. 34 FIGURE 3-10 TWO SOLIDS OVERLAP ONE ANOTHER BY THEIR VOLUME .................................................... 34 FIGURE 3-11 DIFFERENT CONFIGURATIONS OF ADDITIVE FORMS ........................................................... 35 FIGURE 3-12 P UNCTURES PROVIDED WITHIN PLANES ............................................................................ 36

FIGURE 3-13 USE OF TIMBER FRAMES FOR OPENINGS OR ARTICULATED MASONRY TRIM WORK ................ 36 FIGURE 3-14 CLUSTERED AND STAGGERED OPENINGS CREATING VISUAL MOVEMENT ON THE PLANE S

SURFACE ........................................................................................................................................ 37 FIGURE 3-15 GRADUAL INCREASE IN THE SIZE OF AN OPENING ............................................................... 37 FIGURE 3-16 OPENINGS ON A PLANE CREATING CONTRAST WITH ADJACENT SURFACES ........................... 37 FIGURE 3-17 P UNCTURES PROVIDED AT CORNERS OF A PLANE ............................................................... 38 FIGURE 3-18 DIRECTIONAL OPENINGS CAN BE USED FOR CAPTURING VIEWS OR TO BRIGHTEN A DARK

SPACE ............................................................................................................................................. 38 FIGURE 3-19 OPENINGS TO TURN THE CORNERS ..................................................................................... 38 FIGURE 3-20 THE LIGHT WASHES THE SURFACE OF THE PLANE ADJACENT AND PERPENDICULAR TO THE

OPENING ........................................................................................................................................ 39 FIGURE 3-21 P UNCTURES PROVIDED BETWEEN PLANES .......................................................................... 39
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FIGURE 3-22 VERTICAL OPENING CAN BE IN THE MIDDLE OR AT THE CORNER AND EXTENDS FROM THE FLOOR TO CEILING PLANE ............................................................................................................... 39

FIGURE 3-23 THE LIGHT WASHES THE SURFACE OF THE WALL PLANE PERPENDICULAR TO IT AND ARTICULATE THE PRIMACY OF THAT PLANE IN THE SPACE . .............................................................. 40

FIGURE 3-24 HORIZONTAL OPENING CAN BE IN THE MIDDLE OR AT THE CORNER AND EXTENDS ACROSS AWALL PLANE ................................................................................................................................... 40

FIGURE 3-25 THE CEILING PLANE IS LIFT VISUALLY FROM THE WALL PLANES , AND CREATES A FEELING OF LIGHTNESS . .................................................................................................................................... 40

FIGURE 3-26 LIGHT COMING FROM THE OPENING IN THE CEILING PLANE WASHES THE SURFACE OF THEWALL .............................................................................................................................................. 41

FIGURE 4-1 E XTERIOR VIEW FROM THE SOUTHWEST OF C HAPEL OF N OTRE D AME DU H AUT ................. 47 FIGURE 4-2 I NTERIOR VIEW OF THE CHAPEL LOOKING TOWARDS THE SOUTH ENTRANCE ........................ 47 FIGURE 4-3 E XTERIOR VIEW FROM THE NORTHWEST OF K IMBELL M USEUM ........................................... 49 FIGURE 4-4 C HURCH OF THE L IGHT BY T ADAO A NDO ............................................................................ 50 FIGURE 5-1 V OID BLOCKS : MINIMUM BLOCK SIZES FOR 40-48 LATITUDE ............................................ 57

FIGURE 5-2 V OID BUILDINGS FOR BLOCKS IN E UGENE , O REGON ............................................................ 58 FIGURE 5-3 V OID BUILDINGS FOR BLOCKS IN P ORTLAND , O REGON ........................................................ 58 FIGURE 5-4 V OID BUILDINGS FOR SHORT BLOCKS IN S EATTLE , W ASHINGTON ......................................... 59 FIGURE 5-5 MULTIPLE VOIDS , ALLEYS - MULTIPLE VOIDS ON ALLEYS , ALLEYS - MULTIPLE VOIDS ............... 59 FIGURE 5-6 SINGLE VOID - PARTIAL BLOCK , VOIDS - STEPPED BUILDING , MULTIPLE VOIDS - E TYPE .......... 60 FIGURE 5-7 SINGLE VOID , CROSS ALLEYS - SINGLE VOID , SINGLE VOID ON ALLEY ..................................... 60 FIGURE 5-8 L TYPE - EDGE BUILDINGS , L TYPE - OPEN EDGE , PARTIAL E ................................................. 60


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Chapter-1.

1.1

IntroductionAn architectural space makes the users to automatically formulate an unconscious

value judgment as to the quality of that space good or bad. One of the primary reasons

why many good places are thought of as such is that the natural light present has specific

qualities, which are significant in perception of these places. Introducing effective natural

lighting strategies has become an essential goal for any sustainable building. However, since

it is difficult to evaluate its quality and quantity in non-standard spaces through simple rules

of thumb, the use of natural light simulations has considerably increased as a necessary stepto accurately evaluate natural light in buildings. (Golstein, 1976)

The present dissertation presents how the lighting effects of the Sun can be applied

by fairly predicting the intensity and direction of light, its visual impact on the forms, and

spaces by the provision of punctures in the planes of a built mass.

1.1.1 Background

There are many architectural precedents which evidence an understanding of thesensitive use of natural light. But most of the literature relevant to the subject of natural light

in architecture falls into a few general categories. These include technical natural lighting

manuals, studies of effects of light (or the lack of it) on people, or historical investigations of

architectural elements, such as glass or windows. The problem nearly with all of these

sources is that nowhere is there a simple, practical explanation of the subject as related to

architectural design. There has been a range of conceptions concerning this topic; this project

is but one approach. It is a modern set of observations and recommendations, relating to the

design for natural lighting excluding the fenestrations.

1.1.2 Justification

Sun is the rich source of natural light for the illumination of forms and spaces in

architecture. While the suns radiation is intense, the quality of its light, manifested in the

form of direct sunlight or diffuse light, varies with the time of day, from season to season,

and from place to place. At some point, only light form of energy is required whereas at the

other point, both solar as well as light form of energy is needed.


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Natural light is as essential as clean air and clean water. Natural lighting has been

advanced since the dawn of time, and depends upon it for survival. Modern structures often

separate us from this basic need. Buildings with adequate natural light can promote

happiness, contentment, and productivity, all of which are greatly improved with high quality

natural light. A well-thought-out lighting plan requires more than just windows and skylights

on a building. Therefore, it is very necessary to understand natural lighting so that we apply

these studies in designing the buildings. Natural lighting is strongly linked with the aesthetics

of faade design. It is important, therefore, to review the facade design elements in order to

understand the changes in natural lighting of a building.

1.1.3 Need

Since the beginning of civilization, Natural light has had important positive

associations with mans religion, health and culture. Architecture cannot exist but with light.

Environmental responsibilities have become key issues facing the building professions

nowadays. There is growing evidence that buildings, which adopt passive design solutions

such as natural light and natural ventilation show h igher occupants satisfaction .

Natural lighting is the controlled admission of light direct sunlight and diffuse

skylight into a building. By providing a direct link to the dynamic and perpetually evolving

patterns of outdoor illumination, natural lighting helps create a visually stimulating and

productive environment for building occupants. Implementing natural light on a project goes

beyond simply listing the components to be gathered and installed. Natural light requires an

integrated design approach to be successful, because it can involve decisions about the

building form, siting, climate, building components (such as windows and skylights), lighting

controls, and lighting design criteria.

Natural light provides high illuminance and permits excellent color discrimination and

color rendering. These two properties mean that natural light provides the condition for good

vision. However, natural light can also produce uncomfortable solar glare and very high

luminance reflections on display screens, both of which interfere with good vision. Thus, the

effect of natural light on the performance of tasks depends on how the natural light is

delivered. All of these factors need to be considered in designing buildings.

1.1.4 Applicability

Architectural natural light is not solely dependent on sunlight quantity or on thenumber of sunny days per year; it can also take advantage of diffuse skylight (predominantly


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found in overcast climates). As such, direct solar resource is not the sole determinant for

natural light feasibility. A viable option for most building types and locations, it is important

to consider that the architectural response to natural light differs by building type, climate,

and glare tolerability. The study can be applicable to all building types as well, including

commercial office buildings, most spaces within a school (i.e. classrooms, gymnasiums,

media centers, cafeterias, and offices), retail stores, hospitals, libraries, warehouses, and

maintenance facilities.

Some of the Earlier studies serves the purpose to see if it is possible to demonstrate a

clear relationship between the presence of natural light and human performance in buildings.

The implications of the results of this study extend beyond the educational sector. It is

believed that the conclusions can be transferable to other types of buildings, such as offices

and factories, since it is really human performance. If natural light enhances the performance

of students in schools, it is not too large a stretch to suppose that it might also enhance the

performance of adults in office buildings.

1.2 Aim

To study the effect of change/ play with the built mass and punctures (other than

openings) on lighting in a building.

1.3 Objectives

1. Understanding natural light and its characteristics for designing a building.

2. Analyzing the environmental factors affecting the natural light.

3. Defining building mass and punctures, and their categorization.

4. Identifying the effect of building mass and punctures through the history of different

styles in world architecture.

5. Analyzing the effect of building mass and punctures on lighting in todays existing

buildings.

6. Suggesting a set of general guidelines for designing with a renewed sensitivity towards

natural light.

1.4 Scope of work

Natural light strategies depend on the availability of natural light, which is determined

by the latitude of the buildings location. These are also affected by climate and it is


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important to identify seasonal variations, prevailing climatic conditions, particularly ambient

temperatures, and sunshine probability. Knowing the climate is an essential first step in the

designing for natural light. In those latitudes where natural light is at a premium, there have

been serious attempts to maximize the amount of this natural light that enters buildings.

(ECBCS and SHC, 2010). On the other hand, in more subtropical latitudes, it is both

impractical and uncomfortable to admit a great deal of direct sunlight in buildings, but the

need for recognition of the existence of the sky is not denied.

The scope of this study is to design buildings in subtropical climates by providing

punctures for lighting. For all the other climates, where it could be extremes this may or may

not be applicable.

The project proposes an illustration of an integrated approach to the study of

providing luminous productive work environment in large scale buildings by understanding

the role of punctures, and faade elements other than openings in context with the effective

use of natural light. This is not intended to be complete, detailed design handbook. Through

the use of existing research and through the observation of natural lighting provision in

different buildings, the outcome of this project will suggest some guidelines to design with

different examples.

1.5 Methodology

The literature is collected from different sources the journals of ASHRAE, earlier

studies on natural light, case studies on the buildings in which natural light was given

importance while designing, philosophies and Interviews of different architects who play

with forms for the provision of natural light in buildings, books of different authors who

worked on natural light like Dereck Philips. All the collected data is analyzed and

categorized. Different objectives were developed and explained. Suggestions and conclusions

were drawn from the different examples or case studies necessary for the provision of natural

light.


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Chapter-2. Understanding Natural light

Light is as much a "material" for building as the stones, bricks, and other components used inconstruction; for, although there would be no wall without its structural components, the wall has no

real existence for us unless it corresponds to a sensual impression, gained with our eyes and

substantiated with our minds. - (Phillips, 2004)

2.1 Definition of Natural Light

Natural light is a dynamic and ephemeral tool for expressing the quality of space.

Whether its used in the diffuse illumination of a museum gallery or as a dramatic andvariable figure within an enclosed space, the formal and architectural intentions of natural

light should be directly associated with the evaluation of its quality.

2.2 Need for Natural Light

Natural light is free and abundant. Its qualities are recognized and varied. Since the

beginning of civilization, it has had important positive associations with man's religion,

health, and culture. The need for natural illumination in interiors has been investigated by

lighting engineers, Physicians and psychologists for several centuries and thus had a

profound effect on natural light, the science of natural Illumination. Research on the effects

of the deprivation of light, the need for view, and effects on biological process have

confirmed the factual bases for this need. Studies have been conducted on the preferences of

office workers and home dwellers for natural light and sunlight. As one might expect, the

desire for sunlight is strongest where its duration is most limited. Furthermore, this desire

may be proportional in some way to the degree of physical confinement in which particular

activity takes place.

There seems to be relation between sky and weather conditions, and human notices.

Overcast days, for example, make many people depressed, especially when the cloud cover

persists for several days. The long-term version of this sky condition gives rise to what is

known as the "winter blues"; a longer period of depression. By contrast, when one discovers

that the overcast sky has broken end the sun has come out, the mood usually changes to

optimism and general well-being.


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The characteristics of natural light produced are recognized by these two basic sky

conditions, and those of different times of day, based on the growing awareness of weather

and its implications for clothing, shelter, and activities. Louis Kahn expressed his awareness

of this when he stated that the cloud that passes over gives the room a feeling of association

with the person that is in it, knowing that there is life outside of the room.

2.3 Evolution of Means of Providing Natural Light in Buildings

The history of architecture is th e century- old struggle for light, the struggle for the window.

- Le Corbusier

2.3.1 Early History

The quantity and quality of the natural light that enters a room are determined initially by the

window through which it passes. The placement of the window with respect to orientation,

proximity to exterior walls, outside obstructions, and sky exposure all have particular effects

upon the light as it enters. It would seem valuable, at this point in the discussion of sensitivity

to natural light, to investigate the evolution of the window, taking notice of various functions

it was called upon to perform, and effects of gradually increasing sophistication in

manufacturing techniques and structural systems. In the early houses that primitive man built,

the light came from two directions: from the top, via the smoke -hole, and from the side,

through the doorway. McGrath has suggested that these early light-admitting voids,

determined only by necessity, were first steps in an evolutionary process that I say have led,

directly or indirectly, to the open courtyard house and the window, respectively.

The development of the inner court may well have been contributed to by the smoke

outlet via the light -well, and is this connection it is noteworthy that the classic house consisted of a

series of chambers one floor in height grouped round a central court, the external walls surrounding

the group having a few small windows but the main lighting being provided by the doors from thechambers to the court, a system which persisted is Mediterranean countries for a considerable time.

(Raymond Mcgrath, 1937)

The doorway Opening seems to have become the standard void -in -the -wall,

admitting light from one side of a room. The door itself originally acted as a filter or barrier

in the opening, allowing or prohibiting light, physical access/ egress, and penetration of

weather. Over time the half -door, or Dutch door, came into evidence, still providing those

three elements, but with more flexibility -- it was now possible to prevent access while still


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admitting light and air. The vestigial form of this half -door can be seen in the existence of

the half -glazed door, which gives one poor compromise of those three qualities.

Figure 2-1 Doorways- natural lighting from one side of a room

The word window is derived from the Norwegi an word vindauga, meaning

wind eye, and early windows served simply that purpose, to limit the infiltration of

weather. The only filters of incoming elements were shutters of various types. It wasn't until

the Romans that an attempt was made to use transparent glazing materials to keep out the

weather. In the first century A.D, thin sheets of lapis specularis (probably talc) were used

for glazing. According to evidence from excavations in Pompeii and Herculaneum, it has

been determined that some rich Romans had small pieces of real glass for their greenhouses.

This primitive glass was apparently cast in a mold consisting of a flat stone, out of which had

been carved a shallow depression. The public baths in Pompeii also had windows of plate

glass which had been slightly ground on one

side to prevent passersby from looking in. In spite of this evident use of glass as a glazing

material, other substances were more commonly employed in Rome. These included linen,

shells, alabaster, and sheets of mica. Windows of this time in the Par East were occasionally

glazed with mother-of-pearl or tortoise shell.

2.3.2 History of English Natural Light

Of all the civilizations of the modern world, the British seem to have been most publicly

concerned with natural light. They have done the most research, established the most precise

standards and design criteria, and written the greatest number of natural light manuals. Their

concern has included legal statements of man's need for natural light: the principle of "ancient


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light." A series of parameters defining PSALI, or Permanent Supplementary Artificial

Lighting of Interiors, has been developed, further emphasizing their conviction that natural

light should be the primary source of interior illumination. In PSALI, natural light is the

dominant interior light source up to 40 feet from the window. Beyond this distance, it is used

as a supplement to the artificial light, in order to add interest and variety, as well as visual

contact with the outside world. It is in the context of this attitude towards natural light that the

history of English natural light is now discussed. The stone -casting technique of making

glass panes was carried by the Romans to Britain, and was practiced there sporadically for

several hundred years. In Roman Britain, window glass was usually 1/8 -inch thick, with

irregular surfaces, and green or blue in color. This latter characteristic created a feeling of

coolness in some interiors, thus aggravating the perceived sensations of the traditionally

damp English climate. By the fifth and sixth centuries A.D., the French had progressed

further with glass making that the British. In fact, it became such a lost art in England that, in

675, the Abbott of Wearmouth sent to France for craftsmen to make glass for his church.

(Richard Sheppard, 1948). There ensued a revival of the art in England which lasted 200

years, only to be forgotten again from the eighth through the thirteenth centuries. In Norman

and Saxon England, windows were no larger than small slits net near the top of the wall,

sometimes closed by wooden shutters. The restricted size was determined by the prevalence

of violent attacks by rival lords. Glass, even if it had been available, would have been out of

the question as a window material. Needless to say, the diminutive size of Norman windows

greatly reduced the quantity of light entering the interiors of the castles. In order to maximize

this quantity, window reveals were deeply splayed, thereby reducing glare and expanding the

illuminated zone of the room.

Figure 2-2 interior

view-norman window

Figure 2-3 these small; deeply splayed windows on Larsen

Hall at Harvard are reminiscent of Norman windows,

although there is presumably less fear of attack


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In walled towns of this era, windows were somewhat larger, obviously because of the

reduced need for protection from attack. The inhabitants used oiled linen or parchment strips

to seal out the weather. Later they employed ground pieces of horn, set in strips of lead. It

was clear that only those structures that were immune to invading armies were those in which

glass could be used as windows. The only buildings that fit this requirement were churches.

Since the English had lost the techniques of glass manufacturing, during the eleventh and

twelfth centuries most glass in their cathedrals came from France. Every attempt was made to

maximize the penetration of the characteristically gentle British natural light into the

churches.

The initial use of glass in churches was known as "plate" tracery, and was created by

punching holes in plates of stone, and then filling them with small pieces of glass. "Bar"

tracery was the next step in the evolution of windows in the eleventh and twelfth century

stone churches: members of the window frame were built up of separate pieces. This

structure led ultimately to the glazing bar or mullion.

Two external events after the twelfth century had a significant effect on window size

and quality in England. first, coal replaced wood in the glass manufacturing process, reducing

the cost while improving quality. Secondly, law and order became more widespread in the

country, so people were less concerned with protection from attack, and therefore could

consider larger windows for their homes and other buildings.

The glass -making industry continued to grow and produce more refined products,

and cost decreased with higher output, but the size of glass panes remained small.

Nevertheless, Gothic churches increased the intricacy of their glazing, and the light thus

transmitted to the interior became clearer and less colored due to fewer impurities in the

glass.

The richly colored stained glass that is familiar from churches and other religious

buildings originally began as painted glass. As glass- making methods improved, the colors

were impregnated into the glass through selective use of mineral impurities. Medieval

Christianity has been associated7with masses of vivid colored glass depicting significant

religious scenes. As the political and religious intensity of this period declined, so too did the

use of such decorative glass.


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Figure 2-4 (left) The Tower of London's interior demonstrates the "tonal grading" produced by a

succession of vaults. (Right) This building at Yale, built in the 1930's, has references to old Englishwindow design.

With the expansion of technological knowledge arising out of the Renaissance

came more concern for purity and quantity of natural light in interiors. "The decline of

Catholicism and the influence of the Renaissance can be no better illustrated than in this

insistence on light at the expense of decoration -- less obscurity but also less brilliance, more

reason, it might be said, but less significance." The Gothic period was the next important

phase in the development of glass as a building material. As Gerhard Rosenberg stated in theR.I.B.A. Journal of 18 January 1936, 'Without glass, indeed, there could have been no

Gothic."9 The quality of light in Gothic buildings, especially cathedrals, was determined

primarily by the available glass, by the intention of the architect to use as much glass as

possible, and, hence, the structure thus necessitated. By using a structural framework

consisting of massive masonry piers that provided primary support of the building, the space

between these piers could be one huge window. Exterior and interior reveals were splayed in

both plan and section, resulting in better spreading of the light. Glass "lights" were made no

larger than eight inches square, and so were held together by lead strips, producing the

intricacy we recognize. Moldings, also splayed, were needed to keep off the rain because

these lead Joints leaked badly. They also "captured" more natural light, and reflected it into

the interior spaces. The pointed arch from the vaults of the Church itself was carried

consistently in the window; a gable carried the runoff from the window head. Since the glass

was small, and lead -framed, there was a problem of rigidity. As a result, lead glazed panels

could not be more than 2'6" square. This finally determined the minimum spacing of the

stone mullions that held the tracery together. The perception of these windows was not as a


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void, as there would have been had the panes been much larger, as is common today. "The

beauty of the Gothic window, so far as the exterior is concerned is that it presents a textured

surface sufficiently individual to emphasize the window opening and sufficiently patterned to

curtain the void."' After the War of the Roses in the late fifteenth century, there was no longer

in England the worry of attack, and thus the necessity for fortification was far less pressing.

Windows were free to be as large as was desired and practical.

Figure 2-5 A Gothic -style window at Yale shows external splaying of stone elements, which increases

interior illumination

Demand for glass continued to grow, and more foreigners, especially Frenchmen,

were brought over to England to impart their skill to the English manufacturers. It was with

the advent of the sliding sash window and the availability of larger panes of glass, that

English windows underwent their most significant metamorphosis. Window bars began to

shrink. It was no longer necessary for reasons of structure, rigidity, or formality to take up as

much as 30% of a window opening with hers. The trend moved towards minimal glazing

bars, still separating small panes, but producing greater illumination inside a room. In the

midst of the growth in the use of windows and the corresponding increase in interior natural

lighting, the unique English Window Tax of 1697 was enacted. This levy proved to be a

significant restraint on the trend in progress, and more of a burden on the lower classes, who

were already behind the rich in quantity of fenestration. Due to the expense of glass, window

size had become a matter of prestige: large windows implied wealth and influence. The

window tax was imposed on homes with more than six windows, and was worth over at

5/year.

This tax checked the use of windows, but did not alter their design. Existing windows

were bricked up; new houses were built with depressions in the brickwork, corresponding to thewindows that would have been there if the owner had felt inclined to meet the tax, or ready for


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piercing if the tax should be removed; but it remained until 1851 -- a severe and unhealthy limitation

on house design.

It is important to note that the tax was on the number of windows, not on their

area. As a result, the English architect found ways of circumventing the law, even within the

restrictions it imposed, and thereby advanced the evolution of the window.

Windows on ground -floor rooms became taller, rising from skirting level and

terminating just below the cornice line: ... This deliberate attempt to admit light as near the ceiling as

possible on ground- floor rooms suggests that Georgian architects were anxious to make the most use

of available natural light.

Georgian architects developed further another aspect of window design that adds to

the quality as well as quantity of natural light in a room: the splayed reveal. As we saw in

the example of the Norman window, this device not only further spreads the light entering aroom, but it aids in the reduction of sky glare by "grading" the contrast between the window

and the adjacent dark wall, and by reducing one's direct view of the sky. The internal shutters

often used in darkening the window were integral to the design, folding back in- to these

reveals.

Bay windows had been introduced as early as 1401 in England, and went through

several stages of evolution during the ensuing 400 years. During the eighteenth century they

became increasingly popular, and were often used in one of two forms: semi -hexagonal (lateVictorian) or curved (Regency).

Figure 2-6 (left) These shutters fold back into the reveals of the window. They are also adjustable like

venetian blinds. (right) Both types of bays are seen on this facade on Boston's Beacon Hill.

The Industrial Revolution of the nineteenth century improved glass quality to the point that,

due to increased size, strength, and clarity, mullions became unnecessary:

This technical achievement provided an opportunity for an entirely new approach to

window design; but Victorian architects continued to think of windows as a pattern of apertures in an


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elevation, they were obsessed by the conventional idea of fenestration, interpreting that term in a

purely drawing -board sense, and rejecting the possibilities contemporary industry disclosed.

The Victorians were not the only architects to stick to traditional modes of building in

spite of technological advances: the Classical Revivalists did likewise. In fact, the same was

true in this country and continues to be the case wherever an earlier style is emulated or

revived, even though the raisons d'etre for the style are no longer extant nor even

comprehended.

2.3.3 Dutch, Venetian, and Japanese Design Developments

The Dutch were sensitive to the issue of natural light, and were responsible for

some major design developments in this area. Due to its proximity to the sea, much of

Holland's land area was created by reclamation. As cities like Amsterdam grew, the structure

found most efficient for housing and occupying the ground area was a tall, narrow row house

with a gabled roof. The natural result of such design was that all the daylight in these houses

had to come from the gable ends of the building, front and rear. The lower floors were for

living purposes only, and had high ceilings, often as much as 14 feet. The upper floors were

primarily for the storage of goods. Early in the history of Dutch windows, glass was used

sparingly due to extreme expense. In all cases, however, its use was designed so as to

maximize the penetration of natural light. In the sixteenth century, only the upper half of the

windows was glazed; the lower was closed by shutters.

Later, the lower half was glazed with inward -opening casements, but the shutters remained.

Often, the upper part also had shutters, which opened inward. All of these light -control

devices were combined with heavy drapes and curtains to produce a four -framed window

with an almost infinite number of possible configurations. Each time of day, type of weather,

and variety of task being performed demanded a particular type of lighting, and this

extremely flexible system provided this variety. Several characteristics of these Dutch

Figure 2-7 Dutch Windows - Elevation (left)


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windows are of particular importance in this discussion of designing with daylight. First,

these windows extended right up to the ceiling, providing even light over the entire room.

Second, the windows often stretched from one load -bearing side wall to the other: since the

end walls did not support anything but their own weight, this was a very efficient use of

structural infill. The light thus produced/ filtered/ controlled has particular qualities that are

familiar to 'many of us through the paintings of Vermeer and Rembrandt. One always sees the

light playing over the Objects and figures in the painting, and senses the source, but the

window itself is rarely seen. Each painting has a special kind of light, and it is possible to

deduce for each one precisely which combination of open and closed shutters produced that

specific illumination pattern.

This "Dutch lighting" was characteristically high on the wall and, combined with light-

colored side walls and ceilings, gave good modeling, as well as reasonable light penetration

to the rear of the room.

Other cultures have specific attitudes about natural light that provide contrasts to the

preceding examples. The Japanese have aided the penetration of natural light into the deeper

parts of their houses through the use of translucent sliding screens. Clearly, acoustical privacy

is not as important there as is symbolic physical privacy. The "sharing" of light, in this case,

both divides and unifies the interior space.

2.3.4 History of American Natural Lighting

In the early years of the American colonies, the use of windows paralleled their use in

England. The quality of light that is associated with early Colonial houses was largely

dictated by the prevailing styles of architecture in the British Isles, and by the availability of

window glass. The first "lights," or panes of glass, came from the mother country in 1638,

and were small, diamond -shaped, and low in quality. Much of this early American window

glass was blue or purple, and contained many impurities.

Most colonists used oiled parchment as window closure. And, if they wanted glass

(and could afford it), they had to bring it over themselves. Even in 1629, glass windows had

not yet reached any of the more remote parts of England, so it is no wonder that immigrants

to this country were advised to transport their own glass.


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Figure 2-8 although these are not the original diamond -shaped lights, they refer back to early 17th

century windows.

The most common type of window was the hinged casement: these casements

were usually grouped in pairs except at the ends of the house. Dormers, when used during the

seventeenth century, were present in proportion to the number of roofs on the top floor of the

house; in end chimney houses, 1 dormer; in central -chimney houses, 2 dormers. In central

chimney saltboxes, people generally put windows wherever they needed light indoors,

without regard for symmetry on the outside. Sash windows had replaced the tiny -paned

casement.. but only the lower part of the window moved; the upper portion remained fixed."

Whereas window placement in early American homes was based on local need for

light, architects of the Georgian and Federal periods were more concerned with regularity and

symmetry of the window arrangement. Most windows of this time were square -headed, and

were used singly in building facades. The only exceptions to these square -headed windows,

before 1750, were occasional arched windows, placed alone, often over stair landings.

Figure 2-9 lighting through palladian windows

Palladian windows then began to appear, marked by a large, arched -head central window,

and two smaller side lights. These disappeared, for the most part. By 1800, and the only useof triple windows was with square -headed central windows.


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2.4 Characteristics of Natural Light

Reinforced concrete, as a material of construction, offered structural advantages that

brought in a host of possibilities to the design of different spaces. The plasticity of concrete

was used to mold it into different shapes thus bringing new forms to be seen in modernarchitecture. In this homogeneous structural envelope, architects found new ways to carve out

openings for light that could transform the quality of spaces inside a built form. The

monochromatic surface provides a neutral ground to study the characteristics of natural light

which are highlighted to an even greater degree as there is little deviation in the reflective

properties of a built space while comparing different projects.

2.4.1 Defining the parts of Natural Light - Sunlight and Skylight

The natural light chat enters a room from the sky consists of two basic parts. They are

(1) Direct sunlight (insolation) and

(2) Diffuse sky-light.

People often assume that sunlight and skylight can be used synonymously. In

reality, they have very different physical properties and different effects on design. The most

important differences are their intensity, their color, and the extent to which their light is

scattered, or diffused.

The sun is considered a point source of light, often referred to as beam sunlight,

because it is highly directional. Light from the sky, on the other hand, arrives from a large

area and is more or less diffuse, meaning scattered and arriving from all directions.

Beam light will cast a shadow; diffuse light will not cast a distinct shadow. The

intensity of sunlight varies with time of year and location on the planet. It is most intense at

noon in the tropics when the sun is high overhead and at high altitudes in thin air, and least

Figure 2-10 beams of direct sunlight can be magical


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intense in the winter in the ar ctic, when the suns light takes the longest path through the

atmosphere. On a clear, sunny day, the "warmth" of sunlight plus the "coolness" of skylight

give correct color rendering. By carefully orienting a window or a roof -light, one can allow

for the penetration of both elements of natural light, if so desired. (Golstein, 1976)

2.4.2 Dynamics of Natural Light

Another quality of natural light that distinguishes it from artificial lighting is its

dynamic nature. Shifting clouds that momentarily obscure the sun, sudden thunderstorms, the

slowly setting sun, all remind us of the uncontrollable, continually changing weather. This

characteristic that is found so pleasant is also what provided constant impetus for the

development of controllable, predictable artificial light sources. It is argued that because of

its limited duration (1/2 day), and its variation during the seasons, natural light is not an

economically effective light source. These dynamics also prove to be a problem from the

point of view of precise rendering of colors; the eye can recognize colors under different

kinds of natural illumination, but it is not suitable for precise scientific work involving color.

Of course, we may all agree that its advantages far outweigh its dis- advantages; indeed, the

characteristics that are interpreted as one or the other may be the same! Nevertheless, all of

the problems with natural light led one lighting expert to state in 1964 that "Natural lighting

is becoming a lax- It must be noted that this opinion was consistent with the American trend

of placing more importance on high quality, evenly -distributed artificial lighting than on the

quality of interior illumination. This stance has become inappropriate if we desire livable

environments with energy conservation.

2.5 Environmental Factors Affecting Natural Light

The environment (natural) is contrasted with the built environment, which comprises

the areas and components that are strongly influenced by humans. Various aspects of the

environment which affect the lighting of a building are sunlight, change/ variety of

environment and building orientation. It is the purpose here to illustrate these aspects in more

detail.

2.5.1 Sunlight Effect

In his major work Sunlight as Form giver for Architecture, Bill Lam asks the

question . . . The Sun: Problem or Opportunity? And then proceeds to show how the answer
http://en.wikipedia.org/wiki/Built_environmenthttp://en.wikipedia.org/wiki/Built_environment


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can really be both, depending very much on the location of the building. Clearly in hot

climates where the sun is overhead for much of the day the problem is not so much one of

welcome, but of exclusion.

In Britain where the sun is all too rare the answer must clearly be one of welcome

and an early decision when an architect is planning the orientation of his building is to

encourage the entry of sunlight. Sunlight adds to the overall level of light when it is available,

and adds to those other environmental factors such as variety and change, modeling and the

creation of delight. There is a different level of experience when getting up in the morning to

a sunlit world, as experienced from the interior of a building, and it is important that an

element of sunlight is available for some part of the day.

Architects have used the sunlight effect in buildings to create a specific atmosphere,

as for example the shafts of light entering the south side of our great cathedrals; and on a

much smaller scale the use in houses of natural light and sunlight entry from above to provide

necessary functional light to interior areas, where otherwise little natural light would be

available.

The impression of sunlight is also important seen from windows which themselves

admit no sunlight, but where the view of a sunlit landscape or buildings may be enjoyed.

Whenever sunlight is available there is a strong desire to perceive it, and disappointment

when it is unnecessarily excluded.

To sum up, the need for the admission of sunlight is important; the architect must

consider this as a first requirement in planning the location and layout of the building, but in

certain circumstances controls will be needed. (Phillips, 2004)

Knowledge of sun paths for any site is fundamental in designing building facades to

let in light and passive solar gain, as well as reducing glare and overheating to the building

interior. It is important to remember that the position of the sun in the sky is dynamic,

changing according to time of day, time o f year and the sites latitude. We observe the sun in

the northern hemisphere with regards to its paths. The tilt of the earth causes the seasons

which constitutes the difference in the sun paths.

The sun paths are different due to factors such as the:

1) Location (local latitude)

2) Rising and setting position (based on the time of the year)

3) Duration of the day and night


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Figure 2-11 the sun in the northern hemisphere

The ever changing path of the Sun is a result of our seasons. The earth as a whole

receives the same amount of sunlight every day and every year. The apparent movement of

the sun around the earth is relative and due to the earths rotation and orbit. The seasonal

differences in the daily path of the sun are due to the tilt of the earths axis.

2.5.2 Change and Variety

Perhaps the most obvious and certainly the most important aspect of natural light

is its capacity for change, leading to the infinite variety in appearance of the natural light of

the interior. Change is at the heart of natural light, the human body has a capacity for

adaptation, particularly in vision, and the need to exercise this response. Perception reacts to

a degree of change; it is the natural order of things that the appearance of interior spaces alter

with time; and if we have confidence in their continuing reality, it is because change in their

lit appearance allows us to continue an exploration of the spaces we inhabit; an entirely

different measure of experience to the static qualities of spaces lit entirely by artificialsources of light during the day; or where there is no access to the natural light outside. There

is a natural process of renewal in the photochemical processes of the eye as it adapts to

accommodate changes in natural light. First there is the natural change from day to night,

from first light until dark and the need for artificial sources to take over when natural light

fades. Then there are the changes associated with changes of the weather; from bright sunny

days to dark and cloudy or rainy days, there is little doubt that the human spirit soars when

rising in the morning on a bright day, an experience which is less likely to happen when it isdark and gloomy outside.


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Closely associated with changes in the weather are those of the changes of season,

from the winter snows to summer sunlight; each season will have its own character, which as

human beings we accommodate to in our own way ( Error! Reference source not

found.Error! Reference source not found. ); but what is important is that the world outside,

as experienced through the window, provides necessary information of the variety of the

exterior world; whilst leading to subtle changes in the appearance of the interior. (Phillips,

2004)

2.6 Effect of Building Orientation on Lighting

The importance of orientation in a building must be considered at the outset, when the

architect is planning the location of the building on the site, the aim being to ensure the

maximum availability of useful natural light and sunlight to the interior. There may of course

be severe restrictions where the building is set into a rigid street pattern, or where there are

severe external obstructions; but even in these circumstances the best use of the natural light

available should be considered. The architect will have the greatest flexibility to get the

building orientation right on a Greenfield site, where he can plan the site layout to take

advantage of the sun path and the availability of the natural light.

2.6.1 Introduction

Taking an example from residential buildings in the northern hemisphere, and using

the simple fact that the sun rises in the east and sets in the west, it would be normal to ensure

that those rooms which might benefit most from early morning light, such as a kitchen,

morning room or even bedrooms, are placed on the east side, whilst those more likely to be

used in the afternoon or evening such as living rooms face south or west.

There will of course be debate about the desirability of selecting a specific orientation

for a particular use of room and it will be up to the architect to discuss this with his client,

and there may also be conflict with the orientation of a room when associated with the ability

to enjoy a particular view.

As with all architecture a compromise will need to be established which best fits the

needs of the interior function. What is essential is that the orientation of a building and the

interior layout takes most advantage of the natural light available and is a factor taken into

consideration at the outset of the building design.


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Each architectural programme whether an office, school or church, will have its own

specific needs of orientation, and this is of special significance where the interior function is

one requiring the inhabitants to sit in fixed positions, often the case in offices or classrooms.

Another aspect of orientation and one where the mere presence of natural light is reassuring,

is the subconscious desire of people when inside a building to keep in touch with the outside

world, whether to know the time of day or the nature of the weather.

2.6.2 Significance

Well-orientated buildings maximize natural light through building facades reducing the

need for artificial lighting. Some typologies especially housing can be zoned to ensure

different functional uses receive sunlight at different times of the day. Buildings that

maximize sunlight are ideal for the incorporation of passive solar collection techniques that

can reduce carbon use and enhance user comfort. A careful strategy can also mitigate

overheating and glare when sunlight is excessive. You should know how the sun interacts

with your building in high summer and the depths of winter.

Figure 2-12 well oriented buildings

2.6.3 Design Procedure:

Step 1 : There is no single design procedure to design for orientation. However, you

need to model your proposal in a package such as Google SketchUp.

Step 2 : Ensure the building is properly placed on its site in relation to north and the

location either geographically or in terms of latitude or longitude is entered.

Step 3 : Use a sun or shadow tool to model the building at seasonal extremities.


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Step 4 : Remember orientation is about protection and mitigation of sunlight in

buildings as well as accommodating solar gain.

2.7 Summary

This chapter focuses on understanding of natural light. Throughout the history of architecture,

natural light has been dealt in different ways to achieve the desired effect inside a built form.

New materials have been used in innovative ways while experimenting with color, texture,

and reflective properties of the surface to create an interesting play of light and shadow.

Reinforced concrete is one such medium that brought in a new kind of flexibility in dealing

with the overall form, design, and placement of the different openings while exploring the

effect of natural light inside a building. In pursuing this investigation, this chapter addressed

five major subtopics. First, is to define the natural light and the need for it. Second, is to

understand the characteristics of natural light by defining the parts and dynamics of natural

light to illuminate different spaces. Third, is to explore environmental factors affecting the

natural light and the effect of building orientation on lighting.


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Chapter-3. Understanding Building Mass and Punctures

Architecture is the masterly, correct and magnificent play of masses brought together

in light. Our eyes are made to see forms in light; light and shade reveal these forms; cubes,cones, spheres, cylinders or pyramids are the great primary forms which light reveals to

advantage; the image of these is distinct and tangible within us and without ambiguity. It is

for that reason that these are beautiful forms, the most beautiful forms.

3.1 Defining Building Mass

When a building is entered, floor, supports, walls, and a ceiling are seen, all of

which can be studied and perhaps enjoyed, while the space, in the sense that one isaccustomed to think of it, is void: the absence of mass, filled by air. Mass combines with

shape to define form. Mass refers to the size or physical bulk of a building, and can be

understood as the actual size, or size relative to context. This is where scale comes into play

in our perception of mass.

Figure 3-1 Buildings of different sizes

The apparent mass of a building is determined by the actual size of the building, and

whether or not the building shapes and facades are simple or broken into more varied

formsa building should appear to be proportional, or in scale, with other buildings in the

neighborhood.

The exterior of a single building, particularly one that is isolated from other

architecture, does not create a space. It occupies the space of nature. Thus, it may be

experienced as sculpture, in terms of the play of the exterior of a single building, particularly

one that is isolated from other architecture, does not create a space. It occupies the space of

nature. Thus, it may be experienced as sculpture, in terms of the play of masses in a void. The

aesthetics of masses, like that of spaces, is rooted in ones psychology. When a tall tree or a


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mountain is called majestic and a rocky cliff menacing, human attributes are being projected.

Man inevitably humanizes inert matter and so gives the architect the opportunity to arouse

predictable patterns of experience.

The appreciation of mass, like that of space, depends on movement, but this movement

must be physical. It cannot be experienced in anticipation, because, no matter where one

stands to observe even the simplest building, part of it is out of sight. The mass of a complex

building is differently composed from every point of view. The 20th-century art critic

Sigfried Giedion, emphasizing the need for movement in experiencing modern architecture,

suggested that architecture may be four-dimensional, since time (for movement) is as

meaningful as the spatial dimensions. in a void. The aesthetics of masses, like that of spaces,

is rooted in ones psychology. When a tall tree or a mountain is called majestic and a rocky

cliff menacing, human attributes are being projected. Man inevitably humanizes inert matter

and so gives the architect the opportunity to arouse predictable patterns of experience.

3.2 Additions and subtractions in building mass

Structure is the generator of form and space. The structural form needs to be

conceived in a manner that it takes into consideration the internal layout and spatial

configuration rather than just dominating the building design. The outer wall, or the structural

membrane, needs to be planned from the interior as well as the exterior in terms of shaping

space and bringing in daylight.

3.2.1 Subtractive Forms

Generally people search for regularity and continuity in the forms/ masses they see

within the field of vision. If any of the primary solids is partially hidden from the view of a

person, he tend to complete its form and visualize it as if it were whole because the mind fills

in what the eyes do not see (Figure 3-2) . In a similar manner, when regular forms have

fragments missing from their volumes, they retain their formal identities if they are perceived

as incomplete wholes. These mutilated forms are referred as subtractive forms.


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Figure 3-2 the sphere, The pyramid and the cuboid retains their identity even if the base portion of the

solids is removed.

Because they are easily recognizable, simple geometric forms, such as the primary solids,

adapt readily to subtractive treatment. These forms will retain their formal identities if

portions of their volumes are removed without deteriorating their edges, corners, and overall

profile.

Figure 3-3 a portion is subtracted from each of the cuboidal form at their profile edges.

Ambiguity regarding the original identity of a form will result if the portion removed from its

volume erodes its edges and drastically alters its profile.

Figure 3-4 the imaginary lines forming the original profile

Spatial volumes may be subtracted from a form to create recessed entrances, positive

courtyard spaces, or window openings shaded by the vertical and horizontal surfaces of the

recess.


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Figure 3-5 House at Stabio, Switzerland, 1981, Mario Botta

3.2.2 Additive Forms

While a subtractive form results from the removal of a portion of its original volume, an

additive form is produced by relating or physically attaching one or more subordinate forms

to its volume. The basic possibilities for grouping two or more forms are by:

Figure 3-6 physical attaching of two cubes in plan

3.2.2.1 Spatial Tension

This type of relationship relies on the close proximity of the forms or their sharing of a

common visual trait, such as shape, color, or material.

Figure 3-7 two forms combine to form a mixed geometry


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3.2.2.2 Edge To Edge Contact

In this type of relationship the forms share a common edge and can pivot about that edge. In

the Figure 3-8 shown below two cubes are attached at one of their edges to form mix

geometry.

Figure 3-8 two cubes attached at one of their cornices

3.2.2.3 Face To Face Contact

This type of relationship requires that the two forms corresponding planar surfaces which are

parallel to each other.

Figure 3-9 two solids attached by overlapping faces

3.2.2.4 Interlocking Volumes

In this type of relationship, the form interpenetrates other's space. The forms need not shareany visual trait.

Figure 3-10 two solids overlap one another by their volume


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Additive forms resulting from the accretion of discrete elements can be characterized by their

ability to grow and merge with other forms. To perceive additive groupings as unified

compositions of form as figures in our visual field the combining elements must be

related to one another in a coherent manner. These diagrams categorize additive forms

according to the nature of the relationships that exist among the component forms as well as

their overall configurations.

Centralized form - a number of secondary forms clustered around a dominant, central

parent form.

Linear form - a series of forms arranged sequentially in a row. Radial form - a composition of linear forms extending outward from a central form in

a radial manner.

Clustered form - a collection of forms grouped together by proximity or the sharing

of a common visual trait.

Grid form - a set of modular forms related and regulated by a 3-dimensional grid.

Figure 3-11 different configurations of additive forms

3.3 Defining Punctures in Building Mass

Building mass and Space is a very large and abstract concept. It is also difficult to

define architectural space. It is not the opposite of volume. It is not a void, and a void without

light is not a black space. It is not sufficient to make a hole in the envelope of a void to turn it

into space. It is the light coming in through the puncture/ hole that turns the void into a space,

because the space is the light. Space and light are synonyms. The way light is seen is the way

that space is perceived and felt. Of course, in the organization of a building there are other

concepts like sequences, transitions, and many others. But even spatial sequences can be seen

as sequences of light, and of transitions of light. Building forms that serve as containers can

be read as masses that define volumes of space. (Ching, 1996)


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3.4 Categorization of Punctures in a Building

Punctures/ voids that can be provided in a buildings mass are categorized based on its

provision in the planes, at corners and those between the planes. This changes the quality of

the light inside the spaces and the effect produced.

3.4.1 Within planes

A puncture can be located wholly within a wall or roof plane and be surrounded

on all sides by the surface of the plane. It often appears as a bright figure on a contrasting

field or background. If centered within the plane, the opening will appear stable and visually

organize the surface around it. Moving the opening off -center will create a degree of visual

tension between the opening and the edges of the plane toward which it is moved.

Figure 3-12 Punctures provided within planes

The shape of the opening, if similar to the shape of the plane in which it is located, willcreate a redundant compositional pattern. The shape or orientation of the opening may

contrast with the enclosing plane to emphasize its individuality as a figure. The singularity of

the opening may be visually reinforced with a heavy frame or articulated trim work.

Figure 3-13 use of timber frames for openings or articulated masonry trim work

Multiple openings may be clustered to form a unified composition within a plane, or be

staggered or dispersed to create visual movement along the surface of the plane. The

dispersed/ staggered openings can be used to create rhythm by providing the openings at

regular intervals which results in visual movement along the surfaces.


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Figure 3-14 clustered and staggered openings creating visual movement on the

planes surface

As an opening within a plane increases in size, it will at some point cease to be a figure

within an enclosing field and becomes instead a positive element in itself, a transparent plane

bounded by a heavy frame.

Figure 3-15 gradual increase in the size of an opening

Openings within planes naturally appear brighter than their adjacent surfaces. If the contrast

in brightness along the edges of the openings becomes excessive, the surfaces can be

illuminated by a second light source from within the space or a deep-set opening can be

formed to create illuminated surfaces between the opening and the surrounding plane.

Figure 3-16 openings on a plane creating contrast with adjacent surfaces

3.4.2 At corners

A puncture can be located along one edge or at a corner of a wall or ceiling plane. In either

case, it will be at a corner of a space. These openings can be a single one or can be a group/

cluster of openings provided at the corner of a plane along one edge/ two edges.


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Figure 3-17 Punctures provided at corners of a plane

Openings that are located at corners give a space and the planes in which they are located a

diagonal orientation. This directional effect may be desirable for compositional reasons, or

the corner opening may be established to capture a desirable view or brighten a dark corner of

a space.

Figure 3-18 directional openings can be used for capturing views or to brighten a dark space

A corner opening visually erodes the edges of plane in which it is located and articulates the

edge of the plane adjacent and perpendicular to it. The larger tie opening, the weaker will be

the definition of the corner. If the opening were to turn the corner, the angle of the space

would be implied rather than real and the spat field would extend beyond its enclosing planes.

Figure 3-19 openings to turn the corners

If openings are introduced between the enclosing planes at all four corners of a space, the

individual identity of the planes will be reinforced and diagonal or pin wheel patterns of

space use, and movement will be encouraged. The light that enters a space through a corner

opening washes the surface of the plane adjacent and perpendicular to the opening. This

illuminated surface itself becomes a source of light and enhances the brightness of the space.

The level of illumination can be enhanced further by turning the corner with the opening or

adding a skylight above the opening.


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Figure 3-20 the light washes the surface of the plane adjacent and perpendicular to the opening

3.4.3 Between Planes

A puncture can extend vertically between the floor and ceiling planes or horizontally between

two wall planes. It can grow in size to occupy an entire wall.

Figure 3-21 Punctures provided between planes

A vertical opening that extends from the floor to the ceiling plane of a space visually

separates and articulates the edges of the adjacent wall planes.

Figure 3-22 vertical opening can be in the middle or at the corner and extends from the floor

to ceiling plane

If located at a corner, the vertical opening will erode the definition of the space and allow it

to extend beyond the corner to the adjacent space. It will also allow incoming light to wash

the surface of the wall plane perpendicular to it and articulate the primacy of that plane in the

space. If allowed to turn the corner, the vertical opening will further erode the definition of

the space, allow it to interlock with adjacent spaces, and emphasize the individuality of the

enclosing planes.


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Figure 3-23 the light washes the surface of the wall

Natural Lighting and Shading

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