Daylight planning in Denmark's residential architecture

DAYLIGHT PLANNING IN DENMARK’S RESIDENTIAL ARCHITECTURE OCTOBER, 2 2015

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Author: Ioana Farţadi-Scurtu

Consultant: Ronald Toliver

October 2015

7th semester dissertation

Bachelor of Architectural Technology and Construction Management

Lillebælt Academy of Professional Higher Education


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Title: Daylight planning in Denmark’s residential architecture

Author: Ioana Farţadi-Scurtu

Consultant: Ronald Toliver

Copenhagen – October 2, 2015

Heading font: Klavika Light

Body font: Calibri 11

Number of pages (from and including introduction and conclusion): 44

Number of characters (from and including introduction and conclusion – no spaces): 94,819

Total number of pages (including appendix): 79

Total number of characters (including appendix - no spaces): 125,862

Hand-in format: digital (.PDF)

Bachelor of Architectural Technology and Construction Management Lillebælt Academy of Professional Higher Education – Campus Odense

7th Semester Dissertation

© All rights reserved – no parts of this publication may be reproduced without the prior permission

of the author.

Note: This dissertation was completed as part of a Bachelor of Architectural Technology and

Construction Management degree course – no responsibility is taken for any advice, instruction or

conclusion given within!


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This paper involves analyzing the issues and key considerations behind designing with

daylight in Denmark’s residential buildings from the early stages of design. The purpose of

this investigation is to understand the barriers and recommend ways to tackle them to

achieve visual comfort and energy efficiency. This has been acquired through analyzed

theory based research, as well as qualitative data acquired through interviews. The author

recommends that companies improve more towards implementing the knowledge and

philosophy of working with daylight as an early parameter in architecture. Moreover, closer

cooperation with legislators and proper understanding and use of feasible daylighting

technologies are keys to creating a uniform mind-set in the architectural practice of Denmark

in regards to proper daylight planning for residential buildings and achieving good results.


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This paper has been written as part of the 7th semester mandatory dissertation for the Bachelor in

Architectural Technology and Construction Management at Lillebælt Academy of Professional Higher

Education.

The paper addresses the issues and key considerations behind designing with daylight as a primary

factor from the early stages of design in the residential architecture of Denmark. Furthermore, the

paper touches on the subject of some of the most efficient ways to tackle the implementation of

daylighting strategies that are thoughtful in terms of project specifics and achieve visual comfort and

save on energy costs. As specialists of the buildings industry, constructing architects, together with

architects, engineers and other professionals, face difficulties in implementing efficient daylighting

strategies that consider both proper illumination and much needed shading, that causes discomfort

glare and overheating. The author’s main objective in this paper was to observe and interpret the

way daylight is perceived and used in the residential architecture of Denmark and give

recommendations on how to tackle the problems that were raised, in the best possible way, in order

to speed up a long process of proper implementation and use of natural light within the industry.

Key attention has been given to how natural light is and has been a pivotal element in the way

architecture has been shaped throughout the times, as well as its health and economic benefits.

Moreover, the paper addresses what are the most common considerations in projects regarding

daylight implementation and how certain factors differ from company to company or professionals

to professionals within the building industry.

The methodology used to investigate involved secondary data acquired from roughly twenty

different sources, such as books, publications, articles, magazines, as well as primary data, present

through personal interpretations and experience of the author. Moreover, qualitative data has been

achieved through interviews with different professionals relevant to this study.

The author highlights that the benefits of daylight are not limited to energy savings, but they include

plenty of health related positive aspects, as well as increased productivity and motivation among

users exposed to satisfactory levels of natural light during the day. Moreover, the paper presents

that the majority of the problems with thoughtful daylight planning start in the philosophy Danish

architects have and at company level. The author recommends that companies should prioritize the

spread of knowledge and training of staff in regards to perceiving daylight as a very important

parameter from the early stages of design. Working in close connection with consultants and

legislators would facilitate the creation of a uniform mind-set among professionals of the

architectural practice towards working with daylight.


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This dissertation would not have been possible if it wasn’t for the help of a few select people whom I

would like to personally thank for their help, guidance, advice, time and support throughout the

writing of this dissertation.

I would like to thank my supervisor, Ronald Toliver, whose professional expertise helped me write an

academically correct and relevant dissertation and who supported me and guided me throughout the

entire time of writing this dissertation.

I would also like to thank the professionals at BIG architects and at Aalborg University whom I

interviewed, for their time, professional expertise and guidance.

I would also like to mention my other teachers at Lillebælt Academy of Professional Higher

Education, whose guidance throughout the years has proven extremely useful.

Last but not least, I would like to thank my family for their support and for always believing in me.


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Abstract .......................................................................................................................................... 3

Project statement ............................................................................................................................ 4

Acknowledgements ......................................................................................................................... 5

Keywords ........................................................................................................................................ 5

Table of contents ............................................................................................................................. 6

List of figures ................................................................................................................................... 8

List of tables .................................................................................................................................... 8

1. Introduction and problem formulation .................................................................................... 9

1.1 Background information ............................................................................................................... 9

1.2 Problem formulation ................................................................................................................... 11

1.3 Research question ....................................................................................................................... 12

1.4 Secondary research questions .................................................................................................... 12

1.5 Delimitation of work ................................................................................................................... 13

2. Methodology ......................................................................................................................... 14

2.1 Choice of theoretical basis .......................................................................................................... 14

2.2 Choice of research methodology ................................................................................................ 14

2.3 Choice of working method .......................................................................................................... 15

3. Theoretical basis .................................................................................................................... 16

3.1 Designing with daylight - terminology ........................................................................................ 16

3.2 Daylight - general understanding of daylight in architecture ..................................................... 18

3.3 History of daylight in architecture .............................................................................................. 19

3.3.1 Ancient Egypt ....................................................................................................................... 21

3.3.2 Ancient Greece ..................................................................................................................... 21

3.3.3 Ancient Rome ....................................................................................................................... 22

3.3.4 Byzantine .............................................................................................................................. 22

3.3.5 Romanesque ......................................................................................................................... 22

3.3.6 Gothic ................................................................................................................................... 23

3.3.7 Renaissance .......................................................................................................................... 23

3.3.8 Baroque and Rococo (Late Baroque) ................................................................................... 24

3.3.9 Industrial Age ....................................................................................................................... 24

3.3.10 Modern movement (1900s) ............................................................................................... 25

3.3.11 Contemporary architecture................................................................................................ 25

3.4 Benefits of daylight on human health ......................................................................................... 26

3.4.1 Circadian rhythm .................................................................................................................. 26


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3.4.2 Vitamin D .............................................................................................................................. 27

3.4.3 Psychological effects (SAD) .................................................................................................. 28

3.5 Benefits of daylight on energy efficiency .................................................................................... 29

3.5.1 Energy savings ...................................................................................................................... 30

3.5.2 CO2 emissions and carbon neutrality .................................................................................. 31

3.6 Existing daylighting systems and technologies and their feasibility in residential architecture . 32

3.6.1 Side-lighting .......................................................................................................................... 33

3.6.1.1 Lightshelves ................................................................................................................... 33

3.6.1.2 Prismatic panels ............................................................................................................ 33

3.6.1.3 Anidolic systems ............................................................................................................ 34

3.6.1.4 Louver systems .............................................................................................................. 35

3.6.2 Top-lighting .......................................................................................................................... 35

3.6.2.1 Skylights ......................................................................................................................... 35

3.6.2.2 Atrium............................................................................................................................ 36

3.6.2.3 Light pipes ..................................................................................................................... 36

3.7 Building regulations for designing with daylight ......................................................................... 37

3.8 Daylight availability in Denmark .................................................................................................. 38

4. Procedure section ...................................................................................................................... 40

4.1 Interview analysis procedure ...................................................................................................... 40

4.2 Interview data analysis ................................................................................................................ 41

4.2.1 Essential benefits ................................................................................................................. 42

4.2.2 Issues and key considerations .............................................................................................. 43

4.2.3 Implementation strategy ...................................................................................................... 47

4.2.3.1 Company level ............................................................................................................... 48

4.2.3.2 Concept and Schematic Design phases ......................................................................... 48

4.2.3.3 Detailed Design phase ................................................................................................... 49

4.2.3.4 Tendering and Construction phases .............................................................................. 49

4.2.3.5 Post-occupancy ............................................................................................................. 49

5. Conclusion ................................................................................................................................. 51

5.1 Future perspectives ..................................................................................................................... 52

5.2 Assessment .................................................................................................................................. 53

6. Bibliography .............................................................................................................................. 54

7. Appendices ................................................................................................................................ 56

7.1 Appendix I - Figures ..................................................................................................................... 56

7.2 Appendix II – Interview transcripts ............................................................................................. 71


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<Part of Appendix I>

FIGURE 1 ANCIENT EGYPT CLERESTORY EXAMPLE ............................................................................................. 56

FIGURE 2 3D RENDITION OF A CLERESTORY AND ROOF CONSTRUCTION ........................................................... 56

FIGURE 3 EXAMPLE OF ANCIENT EGYPTIAN ....................................................................................................... 57

FIGURE 4 CITY PLAN OF OLYNTHUS. ................................................................................................................... 57

FIGURE 5 THE CENTRAL OCULUS IN THE PANTHEON ......................................................................................... 58

FIGURE 6 HAGIA SOFIA DOME ........................................................................................................................... 58

FIGURE 7 FLYING BUTRESSES IN GOTHIC ARCHITECTURE ................................................................................... 59

FIGURE 8 EXAMPLE OF ROSE WINDOW ............................................................................................................. 59

FIGURE 9 ST PETER’S BASILICA DOME ................................................................................................................ 59

FIGURE 10 INTERIOR OF VIERZEHNHEILIGEN BAD STAFFELSTEIN-BAMBERG CHURCH ....................................... 60

FIGURE 11 INTERIOR OF NATIONAL LIBRARY IN PARIS ...................................................................................... 61

FIGURE 12 VIIPURI LIBRARY IN VIBORG,DENMARK. ........................................................................................... 62

FIGURE 13 RONCHAMP BY LE CORBUSIER.......................................................................................................... 63

FIGURE 14 KIASMA MUSEUM, HELSINKI ............................................................................................................ 64

FIGURE 15 PERCENTAGE OF ENERGY USAGE OF APPLIANCES IN DANISH HOUSEHOLDS) ................................... 64

FIGURE 16 INTERIOR OF THE HARMONY LIBRARY IN FORT COLLINS .................................................................. 65

FIGURE 17 LIGHTSHELVES SYSTEM ..................................................................................................................... 65

FIGURE 18 ANIDOLIC SYSTEM WITH LIGHT DUCT BY D-LINE .............................................................................. 66

FIGURE 19 SECTION THROUGH ROOM USING AN ANIDOLIC SYSTEM ................................................................ 66

FIGURE 20 “DAYTEC” LOUVER SYSTEM .............................................................................................................. 67

FIGURE 21 DIAGRAMS OF VELUX PRODUCTS ..................................................................................................... 67

FIGURE 22 APARTMENT BUILDING COMPLEX BY O’DWYER AND ASSOCIATES ARCHITECTS ............................... 68

FIGURE 23 RENDERED ILLUSTRATION OF A VELUX LIGHT PIPE USED IN A BATHROOM ...................................... 68

FIGURE 24 LIGHTPIPE IN MORGAN LEWIS OFFICE .............................................................................................. 69

FIGURE 25 PSYCHOLOGY OF COLOR CHART ....................................................................................................... 70

TABLE 1 DIFFERENCE OF DL (LENGTH OF DAY) AND DH (DAYLIGHT HOURS) AT VARIOUS LATITUDES ................ 28

TABLE 2 ENERGY SUPPLY REQUIREMENTS ACCORDING TO BULDING REGULATIONS DK.................................... 30

TABLE 3 DAYLIGHT STATISTICS FOR COPENHAGEN ............................................................................................ 38


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“But the architects who are designing rooms today have lost faith in natural

light. By becoming dependent on the light switch they are content with static

light and forget about the endlessly changing character of natural light which

transforms a room each second of the day.” Louis Kahn

Prior to the invention of electrical light, daylight was a primary factor influencing the history of

architecture. From the early forms of habitation, to the more complex ones, architects modeled their

vision in coordination with the sun's position on the sky and its movement from dusk until dawn and

across seasons. However, since the popularization of electrical light in the early 20th century,

daylight slowly lost its importance as a primary factor in shaping the face of our constructions, as

artificial light became more and more used to supplement the need of light.

If we look back into the vast history of architecture, we can understand, without having any

professional knowledge, how important daylight was when architects of the past sketched their

ideas. Ancient civilizations, such as, among others, the Arabs, the Persians, the Greeks and the

Romans, designed their dwellings in perfect harmony with the Sun, creating large, welcoming

courtyards and inviting daylight into their homes as a primary feature. The Romans prioritized

daylight by patenting the idea of solar zoning their cities. This gave the inhabitants access to daylight

in their dwellings. And Vitruvius was the first to describe how daylight should be used in a house to

maximize its effect on visual comfort by recommending the use of “an eastern light for bedrooms

and libraries, a western light for baths and winter apartments, and a northern light for picture

galleries and other places in which a steady light is needed…”1

Moving further in time, we understand how daylight use in architecture is directly proportional to

the advancements of technology. The boom of the industrial revolution caused by the invention of

the steam engine in the 18th century, triggered an impressive migration of the population from the

rural area to the cities. People were seeking better paid jobs and opportunities, but the rapid

increase of urban population led to poor living conditions. This rapid migration of the population,

created a big economical and architectural change, which shaped the face of the cities across the

globe. The ongoing demands for housing led to filthy, overcrowded neighborhoods, with access to

little or no daylight at all. This downfall of daylight usage and unfit living conditions lasted more than

1 Vitruvius, 2002 - quote taken from Boubekri, M., 2014. Daylighting Design: Planning Strategies and Best Practice Solutions. Birkhäuser. pp. 8


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a century, until 1903, when Dr. Niels Finsen2 was awarded the Nobel Prize for his research on

daylight and how it can cure tuberculosis, one of the leading causes of death at the time. This led to

slowly reintroducing daylight as a contributing factor in architecture, especially in the works of, most

notably, the Swiss architect Le Corbusier and the American architect Frank. L. Wright. Wright’s

Usonian style houses are a remarkable piece of modern architecture which benefits from the use of

large, ceiling to floor windows, skylights and sun tunnels, as well as masterfully created shading

systems to achieve the desired visual comfort of the inhabitants without obscuring the exterior

views.

Whilst this trend was shaping in the early part of the 20th century, other technological developments

were taking over the world - the popularization of the electrical light took over the architecture of

the century. Daylight became a luxury, as fluorescent lighting became extremely popular. Rapidly,

architects were faced with pressures from utility companies to replace daylight with electrical

lighting as much as possible. 3

Today, more than 100 years after electrical light became common in households around the globe,

the world is tackling a major problem: global warming. With rising CO2 emissions and other

poisonous gases, architects, constructing architects and other professionals of the building industry

look to go back to clever ways of harnessing natural light into today's architecture to achieve energy

efficiency and cut down on the harmful emissions that are slowly destroying Earth as we know it.

Combined with the numerous benefits it has on human health and behavior, daylight needs to

become again a priority in the building sector from the very early design stages.

From the very first year I spent as a student in Denmark, I noticed how the amount of daylight

available in this Nordic country during late autumn, winter and early spring can affect my day-to-day

productivity. Prior to moving here, I visited Sweden for one week, in early spring, when days are

short and nights are long and cold and I had the opportunity to speak to fellow students about the

influence of daylight on their activities and overall physical and mental health. Depression and lower

rates of productivity were mentioned several times by different individuals, as well as a general

apathy towards normal daily activities. People complained how little daylight they experience during

cold, winter days, as their normal school day starts early, before sunrise and ends close or after dawn

which generally takes place as early as 4PM. After experiencing my first Nordic winter, I agreed

100%. There is little solar activity, and it is generally missed as day-to-day activities take over the

2 Niels Ryberg Finsen (December 15, 1860 – September 24, 1904) was a Faroese-Danish physician and scientist of Icelandic descent. He was awarded the Nobel Prize in Medicine and Physiology in 1903 "in recognition of his contribution to the treatment of diseases, especially lupus vulgaris, with concentrated light radiation, whereby he has opened a new avenue for medical science." source - Wikipedia.com

3 (Boubekri, 2014) pp. 10


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majority of the time span when the sun is present. Moreover, we live in a world where global

warming is not a topic of deliberation anymore. The scientific world agrees that global warming is the

effect of human action. High emissions of poisonous gases slowly kill the ozone layer and expose our

planet to dangerous, potentially deadly solar radiations. Conservation plans on how to cut down

these emissions are a thing of the present, and global warming is a priority for most developed

countries.

Denmark is one of the top countries in the world tackling the problem efficiently. Copenhagen’s

Climate plan 2025 shows that Copenhagen has reduced CO2 emissions by 21% since 2005. The City

Council of Copenhagen agreed unanimously back in 2009 to adopt the “Climate Plan for

Copenhagen”4 a vision to achieve carbon neutrality by 2025. With that in mind, I am lucky to carry

my research and develop further on a subject that captivated my attention long ago, in a country

that sets global warming on the top of their agenda. Denmark wants to building energy efficient

houses, wants to develop public transport that uses green energy and wants to invest in solar energy,

among many other action points described in the aforementioned research. Moreover, 2015 is the

year of the daylight and I consider that the research I am planning to carry with this paper is time

wise, interestingly placed – we have so much information on how to use daylight but we have to first

meet some milestones on the way that are still causing slow developments of the proper use of

natural light in architecture.

Daylight is and will become more and more of a priority in the upcoming years. Specialists

understand now, more than ever and emphasize the endless supply of daylight we have and can use -

“Sun provides constant 23,000 terawatts of energy to Earth. It is about 1500 times more than we can

use.”5 Then how can we use it properly in Denmark’s residential building sector to achieve visual

comfort and energy efficiency, ultimately paving the way to carbon neutrality and saving our

beautiful planet Earth?

As construction specialists in Denmark's building industry, constructing architects, together with

architects and engineers, face several questions in regards to daylight implementation from the early

design stages in a country that experiences little solar activity: Are standard wall openings and plot

orientation in regards to the sun enough? Or the use of more advanced technologies and an ongoing

development in the field are a necessity to achieve energy efficiency and visual comfort in residential

buildings for people living in Denmark?

4 The City of Copenhagen - Technical and Environmental Administration, 2012. CPH 2025 Climate Plan.

5 Velux, 2015. Daylight&Architecture, (12), pp.67-74.


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The answer to these questions will lead towards better understanding the different ways of tackling

the issues and boundaries that current perception and use of natural light in the architectural

practice of Denmark have, as well as using the existing technologies and combining them to

implement daylight in residential architecture from the early design stages in Denmark and other

countries that face similar solar activity.

I would like to investigate the issues and key considerations behind designing with daylight from the

early design stages in order to create a properly balanced daylighting plan implementation strategy

for residential buildings in Denmark to achieve visual comfort and energy efficiency.

Can using daylight as a primary focus from the early design phases influence the ability of improving

visual comfort and achieving energy efficiency in residential buildings in Denmark?

1. What are the benefits behind designing with daylight?

2. What are the issues and key considerations that we need to consider in order to achieve a strong

daylight strategy from the early stages of design in residential buildings in Denmark?

3. How to create a strong and efficient daylighting strategy in Denmark´s residential buildings after

understanding the issues and key considerations we need to face in order to achieve economic

benefits and visual comfort?

For approaching my main research question, I have decided it is necessary to have secondary

research questions instead of hypotheses. Hypotheses are educated guesses based on actual facts

that you either approve or disprove in your research. At the beginning of this paper, I wasn’t as well

informed and educated in the field as I am now, after the extensive research needed to complete

and answer this paper. The secondary research questions are meant to pave a structured and logical

way towards answering the problem and the main research question of this paper. Furthermore, the

secondary research questions form the substance of the analysis and the answer to them create a

comprehensive understanding of the problem.

Moreover, I considered it is important to discuss both issues and key considerations that need to be

considered, because architecture is a vast field, in which many professionals activate. What is pivotal

for one architect in terms of daylighting, may be less important for another. Issues behind designing

with daylight in mind are almost always closely connected to other factors related to the project,

such as the clients, investors, lead architects and engineers, among others and these are obviously

very different from case to case. What is important is to create a general approach towards designing


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with daylight from the early stages of design that could be adjusted to suit needs and specifications,

without compromising on visual comfort and energy efficiency.

The extent of the paper is minimized to Denmark’s residential buildings (with consideration that

results could be used for countries experiencing similar solar activity). The regulations used comply

to BR10 and BR15 for Denmark which is still being worked on.

The paper will analyze and describe the issue and considerations behind acquiring a strong

daylighting strategy for residential buildings in Denmark from the early stages of design and

ultimately how to put together an implementation strategy of daylight planning for residential

buildings in Denmark to harness as much natural light as possible to benefit both economically and in

terms of visual comfort of the users. The research process involves elaborating on the benefits of

daylight, the necessary considerations and issues to be taken into account from the early design

stages and finally how to build a strong daylighting strategy implementation after better

understanding the problems.


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Before considering ways of acquiring the theoretical basis of this paper, I decided to approach the

problem in a logical, structured way. The chapters of the paper are structured in a logical way that

carries the reader through pivotal pieces of information. Therefore, the secondary data information

was carefully selected, analyzed and filtered through my own understanding from various credible

sources. Mostly, I have decided to base my theory part on carefully selected information from books

such as “Made of Light: The Art of light and architecture”, “Daylighting design. Planning strategies

and best practice solutions”, “Building Regulations 2010” and paper reviews “The impact of light in

buildings on human health”. There are others sources, referenced in the bibliography part, but the

ones mentioned above were pivotal for acquiring the knowledge and basis of my research.

Everything used in the theoretical part, unless otherwise stated (referenced through footnotes) is the

result of my analysis and interpretation of the theory read from the aforementioned sources.

After extensive research of the theoretical basis for this paper, I have decided to conduct my primary

research to gain empirical data in forms of interviews with other specialists of the building industry

whose professions are relevant to the subject, but different from each other. This was done in order

to gain insight into how different is the perception towards daylight from specialization to

specialization. I selected the people to interview based on their knowledge and experience with using

daylight in architecture. Two of them are professionals of the architecture and construction practice

at BIG Architects in Copenhagen and the third individual is studying a MSc. in Lighting Design at

Aalborg University campus Copenhagen. The answers are anonymous. The interviews were carried as

qualitative data research, meaning that I was able to gain information and insight along the way,

which, in combination with my previous experience and recommendations formed the primary data.

I was also able to use the empirical data, at times, in combination and comparison with the

theoretical secondary data, to answer my secondary research questions and ultimately the research

question. I used my coordinator’s advice and guidance throughout the entire process, who helped

me gain a better understanding of how to structure and compile a well-written and documented

dissertation paper which is relevant to my field of education.


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The dissertation is structured into 5 main sections.

1. Introduction - includes choice of subject, problem formulation, research question and

hypotheses

2. Methodology - includes delimitation of work, choice of theoretical basis, choice of empirical

data and choice of working method

3. Theoretical basis - evaluating, interpreting and explaining relevant findings based on credible

sources related to the history of daylight in architecture, benefits of daylight, existing

daylighting technologies used in residential projects, building regulations requirements and

Denmark’s solar activity. The theoretical basis is the first step towards reaching the

conclusion and it gives a wide knowledge of the field and the necessary pieces that are

needed to answer the problem.

4. Procedure section - describes, compares and discusses the qualitative data acquired through

interviews with professionals of the building industry, to answer the problem, research

question and secondary research questions in combination and comparison with the

secondary data and personal observations.

5. Conclusion


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As the author of this paper and a person interested in the field of daylight in architecture,

terminology associated with daylight is quite familiar to me, but a certain uncertainty towards some

of the vocabulary that is used in this paper, might lead to misunderstandings. The purpose of this

chapter is to help the reader become familiar with some of the most frequent and basic terminology

used when talking about daylight in architectural spaces.

The reason I consider it’s important to offer the reader some general understanding of frequently

used terms associated with the particular field we are discussing in this paper, comes from the

results of a survey conducted by the National Research Council of Canada. To my surprise, the survey

of more than 150 specialists (architects and engineers) resulted in different understandings and basic

definitions of the world “daylight” in architecture. While architects emphasized visual comfort as a

result of using daylight in their design, engineers pinpointed energy savings, hence the difference in

the basic understanding of the world “daylight” in architectural spaces.6

To avoid misunderstandings, the glossary below contains some of the most commonly used words

when talking about daylight in architecture.

Daylight glossary:7

daylight - “the light produced by the sun during the day”

daylit (space) - “a space which provides daylight as the primary source of daytime illumination to

accommodate the occupants' visual demands, is experienced as a visually and thermally comfortable

place connected to outdoor phenomena, and persistently maximizes electric lighting energy savings

while minimizing peak energy demand.”

sufficient daylight - “describes an amount of daylight that meets the minimum spatial lighting

requirements as defined by consideration of occupancy type and schedule; typically measured on a

horizontal work plane.”

glare - “is a human sensation usually described as either discomfort glare or disability glare. As

defined by the Commission Internationale de L'Èclairage (CIE) in 1957, disability glare is: “Glare which

6 Wymelenberg, K., 2008. Daylight Dialect. In Architectural Lighting.

7 Sources for the definitions are Longman Dictionary of Contemporary English, Dictionary.reference.com and the experts at ArchLighting.com


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impairs the vision of objects without necessarily causing discomfort.” Discomfort glare is: “Glare

which causes discomfort without necessarily impairing the vision of objects.”

daylight factor - (DF) is a ratio that represents the amount of illumination indoors relative to

outdoors at the same time.

lux - “a unit of illumination, equivalent to 0.0929 foot-candle and equal to the illumination produced

by luminous flux of one lumen falling perpendicularly on a one square meter surface. Symbol: lx.”

side lighting – is a daylighting strategy that involves openings in the side walls

top lighting – is a daylighting strategy that involves openings from above, normally through the roof

parameter – a set of fixed limits that control the way that something should be done


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Daylight is the light provided by the sun during the day and the reason so many species on Earth

flourish, reproduce and survive. Earth without natural light, implicitly without the sun, would be

thrown into a scenario taken out of apocalyptic movies: after just a week, the average global

temperature would drop below -17°C (0°F), photosynthesis would stop almost immediately and most

plants would die within weeks of the sun’s disappearance. Apart from several microorganisms, most

of the other animals would rapidly die from lack of food and at some point from extreme

temperatures, as they continue to drop to a whopping -73°C (-100°C) after just the first year.8 These

are just some of the consequences that could happen if the sun would simply “switch off”. Luckily for

us all, the possibility of it happening is null, but it makes a good example of how important daylight is

in keeping life on Earth as we know it.

Daylight has been a primary factor influencing human lives since the beginnings of times. Our body

has a natural rhythm, which is connected and influenced by the natural cycles of light and dark. Prior

to the invention of artificial light, which placed light a “switch” away, humans stayed awake during

the period when the sun was up and slept when it set. Today, we can achieve more during the day,

as we are able to “create” light when switching on our lamps, but our body changed its natural

rhythm that we, as a species, survived on for millennia.

It is self-explanatory that something influencing us for millennia and constituting a major element in

our evolution as a species is regarded as an important aspect in the way we design our dwellings.

Nowadays, we live in a very technological world, where the majority of the work can be done by a

computer and we mass produce in 100% automated factories. Jobs that were 100% human

dependent in the past, are now either fully or partially done by smart machines that ease our work.

At the opposite end, architecture is still a trade carried out by people. Why, you may ask? We have

the necessary technology to computer-control it, but do we really want to do that? Our living spaces

are conceived and built by people for people. They are the places where billions of people settle

down for the night, where our dreams, our expectations, our financial possibilities and our lives are

factors influencing the face of our dwellings. They are an expression of our personalities and our

possibilities that we’ve managed to create through architecture.

As we will cover later in this paper, daylight is a very beneficial natural resource for human physical

and mental health, making it an important factor in building concept. Moreover, daylight has a lot of

financial benefits when it comes to reducing energy costs in buildings and paving a straightforward

way to having more green architecture. The general perception today of daylight in architecture is 8 Wonderopolis, 2015. What Would Earth Be Like Without the Sun?. in Wonderopolis.org.


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similar to that of ancient civilizations: an immense aspiration to embrace and use the endless natural

light we are supplied with in the way we think and build our dwelling because as Le Corbusier, the

famous Swiss architects, pinpointed “Architecture is the masterly, correct and magnificent play of

masses brought together in light.”9

In order to understand the significance of proper daylighting and some of the issues we face today in

implementing it, it is important to take a look at the history of daylight in architecture and

understand how daylight has influenced it over the centuries, as well as become acquainted with the

strategies that architects used in the past to bring natural light indoors.

From the early forms of habitation, daylight was an active element of dwellings, informing the

inhabitants of the difference between day and night and later, as architecture became more complex

with the ongoing discoveries and technological developments, penetrating the buildings through

windows and openings to provide much needed light and warmth. The history of daylight in

architecture is strictly connected to the technological advancements of engineering and the

evolution of glass manufacturing.

The primary vehicle introducing natural light into dwellings was and still is the window. Even though

it changed shape, design and has evolved a lot over the centuries, the primary purpose is still the

same - bringing natural light into our buildings. Windows have been used to allow natural light to

illuminate the interiors of our constructions and to create a comfortable indoor climate by balancing

the temperature difference between the outside and the inside. Over the course of history, people

have used thin slabs of marble, sheets of mica or oiled paper10 for window infills, materials which

didn’t generate enough thermal insulation to meet satisfactory comfort levels. It was not until quite

recently, in the 17th century, that large panels of glass were first fabricated and resembled the

window glazing that we are familiar with today.

Nevertheless, despite all the changes in design, position, dimensions, materials, orientation, etc.

windows are the most important feature in architecture; they are the “eyes” of a building and they

create the first experience a visitor has at first sight. It’s to no surprise that we continue to develop

and innovate on this matter even today. We now have a good understanding of the visual aspects of

windows and design considerations, but we strive to achieve energy efficient glazing with extremely

tall windows. In a country such as Denmark, where architects and customers alike want big,

welcoming windows for obvious reasons (inviting as much daylight as possible into the construction)

9 Le Corbusier, 1924. Vers une architecture. Paris: G. Cres et Cie.

10 Phillips, D., 2004. Daylighting: Natural Light in Architecture. Amsterdam: Elsevier, p.3.


20

but have to face harsh a climate, energy efficiency in windows is a priority. Velux is one of the top

manufacturers studying the benefic effects of proper daylighting use in buildings and the ongoing

development of improving their U-value.

In order to gain a better understanding of the current issues we face in designing with daylight and

create ingenious strategies for residential buildings, we need to look back at the history of daylight in

architecture and see how, with little to no technology, people revolved their architecture around a

similar scope that remained actual for centuries - presence of natural light indoors and how they

evolved their space and light understanding from early primitive design solutions to beautiful crafted

renaissance domes and modern skylights.

Prior to industrialization, civilizations used daylight as the primary way of illuminating interiors.

Where needed, lamps and candles were used to supplement the scarcity of natural light. The shapes

and openings of ancient constructions were focused on attracting as much of the exterior light inside

as possible. Therefore, daylight was primarily the factor that influenced the face of the famous,

ancient constructions that we know from history books today. With the existing advancements of the

time, natural light was used as an advantage to the inhabitants; in areas with plenty of natural light

and warm climates, openings were reduced in size and architects used mediums to diffuse the light

in order to prevent glare, while in northern climates, openings were bigger to allow more light to

illuminate and bring warmth inside.

Architects of the past, especially those of Ancient Rome, Ancient Greece and Egypt, also associated

light with divinity and purity, hence natural light was sought in altars and interiors were designed for

optimal light penetration in prayer temples. They understood the importance of using light in

correlation with the denoted special scope of the building or the room in a house. As we cited in the

beginning of this paper, Vitruvius was the first to theorize the different lighting setups for the rooms

of a house with “a eastern light for bedrooms and libraries, a western light for baths and winter

apartments, and a northern light for picture galleries and other places in which a steady light is

needed…”


21

Egypt is a country experiencing good amounts of natural light and a hot climate. Therefore, architects

of Ancient Egypt designed their buildings to prevent glare and minimized the dimensions of wall and

roof openings. As many other civilizations to follow, Egyptian architects were limited by the

advancements of structural understanding of the time; the opening in the walls and roofs, were

limited by the rather short spanning of stone (the primary material used in Ancient Egypt as carrying

structure). The deep plans of the buildings were generally daylit through the use of clerestories. In

fact, the earliest use of a clerestory is found in the temples of Ancient Egypt. Architects used it to

bring light into deep plans, which, otherwise would suffer from a massive lack of light. (Figure 1 and

Figure 2)

For regular dwellings, people used regular sized windows and the entrance door to allow natural light

inside but the interiors were generally protected from the light due to extreme temperatures. Clay

houses with minimum openings were the most common form of habitation during Ancient Egypt,

generally protecting the inhabitants against high outside temperatures. Natural light was abundant in

the courtyards, which were a general feature of early residential Egyptian architecture. (Figure 3)

In Ancient Greece, most of the daily activities were carried outdoors and interiors were designed as

shelters away from the temperatures outside. Minimal openings were used and light had more of a

spiritual meaning for early Greeks. Evidence suggests that the layout and orientation of Greek

temples were aligned to the position of the stars and planets in the Universe. One example that is

thought to be aligned towards Sirius, is the temple at Eleusis (525BC). 11

Probably the most popular monument of Ancient Greece is the Parthenon on the Acropolis (c. 447-

438BC). Light at the Parthenon only penetrated the interior through the main door, but the fully

gilded statue of the goddess Athena was positioned at the edge of a reflecting point, offering

splendid reflections. Ancient Greeks understood the importance of light and created solar zoning of

their cities, offering solar access to all houses for lighting and heating purposes. Greek houses were

positions in cities with a north-south orientation, designed to take advantage of passive solar

heating. 12

An example of Greek city built within the solar zoning criteria is the city of Olynthus. Streets in

Olynthus were built perpendicular to each other, and designed to run in the east-west direction,

allowing houses to be built with a predominantly southern exposure. (Figure 4) "The houses that

faced south on the street and south to the sun were entered through the court, straight from the

11Chepchumba, N., 2015. History of Daylighting: A comparative analysis across the periods. 12

Bronin, S., 2009. Solar Rights Review. Boston University.


22

street. The houses that faced north to the street and south to the sun were entered through a

passageway that led from the street through the main body of the house and into the court, from

which access was gained to all other spaces."13

Early romans were great engineers, focusing their architecture towards building spectacular

aqueducts, viaducts, palaces and theatres, were light played a functional role. Their technological

advancements, created the possibility of greater openings that could capture more light. Popular

features of roman architecture are the barrel vault and the dome. With the reintroduction of the

ancient clerestories and use of oculus, light entered buildings in sections. (Figure 5) A good example

of clever use of light in Ancient Rome is at the Pantheon, where with the movement of the sun, light

entered and gradually illuminated the intricating details on the walls.

The architecture of the byzantine period is, most significantly distinct through the use of the dome

supported at four corners that covered a rectangular floor plan. This structure resulted in a central

dome, surrounded by secondary spaces covered by half domes. The Christian churches of the period,

particularly those in the eastern cultures of Byzantium, focused on developing the close relationship

between architecture and light, primarily through the use of mosaic applications and gilded

structures to create splendid interior lighting effects. The mosaic used in Byzantine architecture was

made using small, cubic shaped ceramics, on top of which a thin layer of color was added and finally,

everything was covered in a layer of glass. 14This way, the cubes reflected and refracted light,

creating an effect of shimmering light that changed with the movement of the individuals in the

room. The best example of mosaic use is at Hagia Sofia in Constantinople (532-537), monument

dedicated to the Roman Emperor Justinian. The effect of the dome of Hagia Sofia, weightless in

appearance, was achieved by creating over ninety windows at the base of the dome. The building

was flooded by light in a circular pattern and illuminated the gilded cladded mosaic on the walls. At

night, a ring of oil burning lamps, hung from the dome, created a splendid, mesmerizing effect,

offering a great example of how natural light and artificial light were used as a central design point in

architecture centuries ago. (Figure 6)

The Architecture of the Western Christian world had little light penetration due to heavy masonry

walls and vaults and the materials they used indoors. Interior were therefore dark and shadowy. One

of the primary means of construction in the Romanesque period was the circular arch. The use of

13

Butti, K. and Perlin, J., 1980. A golden thread. Palo Alto: Cheshire Books, quote found in http://www.lowtechmagazine.com/2012/03/solar-oriented-cities-1-the-solar-envelope.html.

14 Chepchumba, 2015


23

such construction methods allowed for windows to be punctured more easily, but they remained

relatively small due to thick bearing walls. Still, the early Romanesque churches and cathedrals

developed the use of clerestories, lanterns and domes to allow natural light penetration. Combined

with the eastern light coming from the windows behind the altar, the Romanesque use of light in

architecture created a lighting strategy very much used to this day in Christian buildings. During this

period, rose windows15 began to slowly appear in Christian architecture, with the term being fully

defined later during the Gothic period that followed. The rose window has its beginning in the

Roman oculus (See Figure 5 - The Pantheon oculus) serving a similar scope - illumination of the high

ceiling interiors and mural art of the walls in correlation with the sun’s movement.

The Gothic period is a more defined and mature continuation of the previous, Romanesque

architecture, with the elevated stone masonry structures reaching the highest level of sophistication

and engineering ingenuity. Development of the pointed arch and vault, gave architects the possibility

of intersecting roof vaults of different heights. A monumental structural development which shaped

the face of architecture was achieved during the Gothic period - flying buttresses16. (Figure 7)

For the first time in history, external walls became thinner and lighter, losing their primary role of

carrying the roof load. This meant bigger openings covered in stained glass, supported by parallel

buttresses that transferred the load of the roof from the bearing walls. The work of Abbot Suger,

believed to be the developer of early Gothic architecture, defined natural light as a divine resource.

Therefore, Gothic architecture is the architecture of increased openings and transparency in

buildings and larger areas of fenestration glazed in colored glass. The monumental cathedrals and

churches of Europe, many of which stood the test of time, are filled with majestic, colorful light

provided through rose windows and big, stained glass windows. (Figure 8)

The Renaissance was the cultural revival and rediscovery of the ideals and knowledge of Ancient

Greece and Ancient Rome. 17Compared to the previous period, Romanesque and Gothic, which

sought to build with light, the architecture of Renaissance, focused more on the art of antiquity and

proportions prevailed over spatial awareness acquired through light. Still, natural light was

incorporated by architects into their designs. Similar to a sculptor that uses light to shed beauty on

15 Rose window - often used as a generic term applied to a circular window, but is especially used for those found in churches of the Gothic architectural style and being divided into segments by stone mullions and tracery. (Source: Wikipedia.com)

16 Flying buttress - also known as an abutment system is a projecting or free-standing support built into or against the exterior wall of a cathedral, which steadies the structure by opposing the lateral thrusts from the vaults. (Source: Athenapub.com, 2015. Gothic Glossary)

17 Wikipedia.com – Renaissance


24

its art, Renaissance architects used light to enhance beautiful interiors. One of the best examples of

natural light used in Renaissance architecture is Michelangelo Buonarroti’s dome for the St. Peter’s

Basilica in Rome (1506-1626). The use of high openings and introduction of a large lantern at its apex,

allowed natural light to flood the high ceilings plan of the church.18 (Figure 9)

Baroque is defined by the revival of light in architecture during a period defined by a great interest in

theatre and opera in which light plays a pivotal role. The architecture of Baroque saw new lights in

terms of geometry and decoration, as well as the introduction of hidden and recessed openings that

offered complexity of light on the top levels, while the lower levels remained somehow dim and

mystical. Baroque and Rococo are defined by jocular and florid forms, curves and colorful lights, a

general richness to the design and spectacular use of daylight. The “Baroque dome and lantern has

often been compared to the human eye mimicking the form of the iris, controlling the way in which

light enters a building.”19 Another distinct use of light during Baroque and Rococo is found through

the use of elaborate spaces defined by mirrored surfaces and use of white and gold, thus creating a

dramatic depth of light in the interiors. The complexity of the interiors, combined with the

predominantly white and golden interior decorations, envisioned the joy of being in the presence of

God at the time. (Figure 10)

In general, Rococo is a style more predominant in interior design than in general architecture, but its

understanding and use of light is still a great development by showing the importance of materials

and choice of colors in achieving a good daylighting strategy.

The technological advancements of the time, mainly in the area of structural engineering, gave

architects new horizons in terms of designing with large openings and glazed surfaces. If, for some

time after Baroque and Rococo, the architecture shifted to a more classical approach, the invention

of the lightweight cast iron structures meant that buildings could finally break free from the

limitations imposed by heavy masonry walls. The development of structural frames and the

availability of steel membranes, meant that buildings could be supported by columns and the

exterior walls became just leafs protecting the interior from the outside environment. Slowly but

steadily, architects started to understand and correlate the engineering developments with ways of

controlling and manipulating daylight into interiors. One of the first examples of constructive use of

natural light in the industrial era is seen in the National Library in Paris (1860-1868). The vaults,

18

(Major, Speirs and Tischhauser, 2005) pp. 32

19 (Major, Speirs and Tischhauser, 2005) pp. 33


25

supported by slim columns, are lit from above through a roof light which sheds light on the high

ceiling plan. (Figure 11)

With little to no structural limitations, the architects of the early 20th century carried a continuous

path of daylight integration in architecture. Modern architects understood and used ancient

principles of bringing natural light into interiors, while also incorporating modern construction

methods and principles. Important names in the architecture of the 20th century are, among many,

Frank. L. Wright, Alvar Aalto and Le Corbusier. Mainly, architects of the time had the freedom to use

materials and colors that better reflected and refracted light, thus creating intricating juxtaposed

surfaces. Deep, overhung eaves and ceiling to floor windows (a possibility of recent developments in

glass manufacturing), defined the architecture of the early 20th century. Moreover, electrical light

was now widely popular and was being employed by architects to enhance and play an important

role in illuminating interiors.

One of Northern Europe’s pivotal architects of the modern movement is Finnish architect Alvar Aalto.

Aalto created methods to generate soft, indirect light through specially shaped and placed roof lights

that stopped glare, while still providing sufficient light. Let’s remember that he predominantly built in

Scandinavia where daylight isn’t abundant as in other places in the world. Still, the use of overhead

lights, considerably improves the overall interior illumination of a space. Moreover, he employed the

use of artificial lights to create a similar daylight effect at times when natural light was scarce. (Figure

12)

In one of his most distinctive works, Notre-Dame-du-haut, Ronchamp (1955), Le Corbusier used

indirect light to create an interior that has “the emotional appeal that is based on the shadowed

dimness of indirect lighting, in which form is only vaguely revealed.” 20 Light penetrates the interior of

the church through deep apertures and hidden, recessed lanterns, creating a show of playful light

and shadows. He coined the term “canon à lumiere” which is a form of light shaft that is directed

towards the sun.21 (Figure 13)

Today, architects have a wide variety of materials, building and lighting technologies to use with their

designs. With a world developing at a rapid pace, architecture is the expression of functionality and

ongoing demand. Light is again a major focus in architecture, as energy consumption has skyrocketed

20Stirling, J., 2011. 1956 March: Le Corbusier's Chapel and the Crisis of Rationalism (Ronchamp, France) in Architectural-review.com.

21(Major, Speirs and Tischhauser, 2005) pp. 40


26

and demands for greener and environmentally friendly architecture are part of the contemporary

reality. Today, we have such technologies that allow buildings to change, adapting the indoor climate

with the user’s individual preferences and exterior conditions. Clever daylighting technologies, which

we cover in the next chapters, impose no limits to where daylighting can span in architecture.

Scandinavian style, in particular is described by a sense of neutrality and softness of light.

Contemporary architecture in Northern Europe eludes spatiality and use of overhead lighting

technologies to allow as much natural light as possible to enter the interiors. (Figure 14)

Centuries ago, people were interested in the way daylight affects human life and how it can be

incorporated into architecture. Today, architects, constructing architects and lighting specialists are

still following the same path. The purpose of this chapter was to create a sense of understanding of

some of the most predominant and important daylighting strategies used throughout history that

have been continuously improved and reused by architects to achieve the same effect: intelligent use

of daylight in architectural spaces of all types. Ultimately, the results can be used further to

understand which are the most feasible technologies for our daylighting strategy in the residential

buildings of Denmark.

Natural light is essential for the human body to function properly. Recent studies have linked lack of

exposure to daylight to severe illnesses and general apathy. Replacing the natural light with artificial

one on a consistent basis and at night, when our body is supposed to rest, increases the risk of

developing type 2 diabetes, high blood pressure and certain types of cancer.22 In the following pages,

we will cover some of the issues that insufficient exposure to daylight can cause, highlighting through

them the benefits daylight has on improving our quality of life.

The amount of natural light available in your home, at work or in places where you spend the

majority of your time, can affect the way you feel and how energetic and productive you are during

the day, as well as the quality of your night sleep. But why is natural light so important for the human

body? The answer is simple - our internal body clock, scientifically known as the circadian rhythm.

The circadian rhythm is observed in living creatures and is defined as “a daily cycle of biological

activity based on a 24-hour period and influenced by regular variations in the environment, such as

the alternation of night and day.”23 Our internal body clock helps us function properly and offers

balance to the way our body copes with external factors. Unfortunately, due to the extensive use of

22 Naik, A., 2015. How light affects your health. in Netdoctor.

23 Dictionary.reference.com


27

artificial light, we, unconsciously disrupt the normal functioning of it. One of the first things we

experience when our internal body clock is not in perfect sync is how tired we feel. To regulate our

body’s performance, doctors recommend to spend as much as 1 to 2 hours per day outdoors, to try

to be as active as possible and minimize the use of artificial light after sun-set. It’s also advisable to

try to go to bed before midnight, so that our body can experience all stages of sleep before waking

up.

Besides being an important factor in balancing our circadian rhythm, natural light has multiple other

impacts on the way our body functions. Vitamin D, an important nutrient that helps absorb calcium

and phosphorus (both equally important in normal growth and proper development of bones), is

produced through UV-B exposure of the skin. If we have a regular, normal exposure to sun, our

bodies can produce the equivalent of 80% to 100% of their required Vitamin D levels24. Food is also

another source of Vitamin D, but it is less effective and not sufficient to supplements our body’s

need.

Studies have shown that people with mobile dysfunctions and elderly population, experience a

deficit of Vitamin D especially during the winter, when natural light is not as abundant as the rest of

the year due to short days and longer nights. Moreover, Vitamin D deficiency has also been found

among women living in Middle-Eastern countries. Because they cover their bodies in good

proportions, they lack exposure to natural light, which, otherwise is abundant in the region.25 Old,

oriental dwellings featured an internal courtyard that welcomed plenty of daylight into the intimacy

of the house, where Middle-Eastern women could unveil and expose their skin, supplementing the

need of Vitamin D. Modern lifestyle and a change in the traditional architecture of the region, shows

an abandonment of the featured internal courtyard of oriental houses in favor of secluded,

postmodern apartments with poor daylighting considerations.

Scandinavian region, together with other high latitude countries are no strangers to lack of daylight,

therefore without proper Vitamin D supplements, people living in such places are faced with high

deficiencies and all the health risks associated with them. Months of the year, daylight is available for

a few hours every day and it’s generally during the time that people spend at work or at school.

24 Glerup, H., Mikkelsen, K., Poulsen, L., Hass, E., Overbeck, S., Thomsen, J., Charles, P. and Eriksen, E., 2000. Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited. J Intern Med, 247(2), pp.260-268.

25 Saadi H.F., “Efficacy of daily and monthly high-dose calciferol in Vitamin D deficient nulliparous and lactating women” in “American Journal of Clinical Nutrition” ; 2007 & Hobbs, R., Habib, Z., Alromaihi, D., Idi, L., Parikh, N., Blocki, F. and Rao, D., 2009. Severe Vitamin D Deficiency in Arab-American Women Living in Dearborn, Michigan. Endocrine Practice, 15(1), pp.35-40.


28

For example, the number of hours of daylight in Copenhagen before 8AM and 5PM (normal working

hours) is minimized at its peak in December to a staggering -1hr and 07 mn (Table 1).

Lack of daylight exposure doesn’t just affect on a physical level. Psychologically, insufficient levels of

natural light can cause seasonal affective disorder, shortly known as SAD. SAD is a sort of depression

which occurs during winter and it’s directly linked to an imbalance in the brain chemicals serotonin

and melatonin. At high levels of light, serotonin is secreted, which is responsible for our state of

alertness during the day. 26At low light levels, melatonin decreases and sleepiness occurs. When

melatonin increases, serotonin decreases and vice-versa. These two hormones are part of our sleep-

wake cycle which happens in coordination with our circadian rhythm over a period of 24 hours.

Presence or absence of light influences our human endocrine system to such an extent that it cannot

properly regulate itself without sufficient exposure to natural light.

Problems occur when these cycles are disrupted and normal secretion of melatonin and serotonin is

suppressed. Improperly daylit dwellings are a major reason that disrupts the normal hormonal cycle

of our bodies, but studies have also shown that excessive exposure to self-luminous devices (our

computers, phones, tablets, etc.) can also produce disruptions in the regular secretion, especially if

used at high peaks of melatonin secretion (at night). 27This means that regular use of self-luminous

devices when there is no natural light available, can trick our bodies into suppressing melatonin

production, creating an imbalance in the natural rhythm of our bodies. Luckily, intelligent daylighting

26 (Boubekri, 2014) pp. 28 27

(Boubekri, 2014) pp. 29

Table 1 shows the difference of DL (length of day) and DH (daylight hours) at various latitudes. The higher the

latitude, the less daylight hours people experience during the day, therefore a focus on improving the use of

daylight in architecture is a very interesting and actual problem in the Nordic regions and, in our case, in Denmark.

(Courtesy of: Boubekri M., 2014 pp. 29)


29

technologies can prepare our dwellings to offer us more daylight. As for the self-luminous devices,

there is an answer to that as well - limited exposure before bed and applications that dim the

screen’s brightness and adjust the light’s color to imitate that of the natural light cycle on a 24 hours

basis.

SAD is especially found in people living at higher latitudes. Symptoms include sleepiness, lack of

energy and general apathy. If we offered more importance to how we live our lives, the number of

SAD sufferers would be greatly reduced: increased time spent outside is a great solution to diminish

the symptoms. Architecture wise, it is important to allow as much light inside, especially in office

buildings and at home. Placing desks closer to windows in offices and trying to focus our house

around the brightest areas are essential, fast problem-solving remedies. Don’t be discouraged by the

general overcast sky present during autumn and winter in Denmark, as studies show that even on

gray, overcast sky, zenithal light is intense enough for several hours during the day to ensure

sufficient levels of lux that could potentially prevent the symptoms of SAD. 28

It is safe to assume that architecture plays a vital role in the way our body functions. As we’ve

understood from this chapter, insufficient exposure to daylight highly increases our chances of

illness. There is a lot to achieve if we would consider the benefits of having daylight penetration in

our homes as a very important feature of design, especially in places, such as Denmark, where

months of the year, daylight hours are limited and our exposure is being compromised by day-to-day

life activities. Steps as simple as furniture placement, opening sizes and orientation in relation to the

sun are some of the most basic, efficient and inexpensive first-hand solutions for architects,

constructing architects and other professionals of the building industry when creating design

concepts. First and foremost, architecture is built for us to leave in and experience, so our well-being

should be a priority from the early stages of design, especially when building residential projects and

office buildings, as these are the places where we spend most of our times in.

There’s no surprise in saying that the overall energy use on the planet is increasing at an alarming

rate and as more and more developing countries experience economic growth, the consumption of

energy is not subject to change. Worryingly, it is expected to increase in the upcoming years. We

should be well-aware of the change that the building sector is capable of making in lowering the

increasing use of energy. Statics show that the building sector accounts for over 40% of the total

energy use on the planet and more than 45% of the total CO2 emissions. 29 These are some worrying

28 Pail, G., Huf, W., Pjrek, E., Winkler, D., Willeit, M., Praschak-Rieder, N. and Kasper, S., 2011. Bright-Light Therapy in the Treatment of Mood Disorders. Neuropsychobiology, 64(3), pp.152-162.

29 (Boubekri, 2014) pp. 14


30

facts and even though several countries are making huge progress in trying to achieve carbon

neutrality and decrease the average energy consumption, they account for just a small percentage of

the world’s population.

On this chapter, we will focus our attention on the average household energy consumption in

Denmark and the benefits proper daylighting can bring in cutting them down as well as the energy

supply requirements trend in Building Regulations regarding new residential buildings. Moreover,

we’ll touch the subject of carbon neutrality by 2025 and understand why people are becoming more

and more interested in daylight to pave the way to it.

So why is daylight so important when discussing energy efficiency? The most important pro-

argument is the potential of reducing the general reliance on artificial lighting for indoor illumination.

In the Danish Building Regulations, residential buildings fall under a slightly different energy

consumption yearly requirements compared to offices, schools and other building types.

The result accounts for energy supply demands for heating, cooling, ventilation and domestic hot

water. Lighting, in this case, is not regarded under the yearly requirements for residential new

buildings, because it does not account for as much demand of energy supply as the heating, cooling,

ventilation and domestic hot water. Lighting falls under household appliances, and it is the second

most energy consuming one in this category. (Figure 15)

Still, table 2 shows the increasing importance that energy supply requirements have experienced

over the last 20 years in the Danish Building Regulations and how Denmark is trying to cut them

down by imposing strict regulations for new buildings.

Comparisons between versions of the Building Regulations from 1995 until today and the upcoming

two versions for 2015 and 2020, show important changes in terms of yearly energy usage

requirements for a new 150m² single-family house.

BR version Example (for new buildings) Yearly energy usage requirements

Building Regulations 1995 150m² single-family house 105 kWh/m² per year


Building Regulations 2010 150m² single-family house 63.5 kWh/m² per year



Table 2 indicates the difference in energy supply requirements for heating, cooling, ventilation and domestic

hot water. (Courtesy of: Danish Energy Agency, “Energy Efficiency Policies and Measures in Denmark”, 2012

Available from: http://www.ens.dk)


31

We can see a steady decline in energy consumption for artificial lighting from 17% in 1999 to 12% in

2008. This decrease, though, is mostly attributed to increasing usage of energy saving bulbs, and not

that of proper daylighting in residential buildings. Based on this, I consider that an improvement in

the way we bring daylight into our houses can significantly affect these statistics.

Most importantly, energy usage for artificial lighting is bigger during the winter and generally people

feel the visual need to turn on electrical lighting because the sky is predominantly overcast, thus not

enough daylight is available. As we mentioned in the previous chapter, even on overcast skies,

natural light has the capability to supply human need, but in order for it to do that, it needs to get

inside in ingenious ways, specially designed and used for places where natural light is not plentiful.

This gives us the understanding that we could minimize the need to use artificial light during winter

days. If only we could bring natural light inside in a more thoughtful way. The result of this would not

only mean improved visual comfort and plenty of health benefits, but also an important decline in

energy usage for indoor lighting during periods of the years with limited daylight hours. Of course,

winter afternoons and evenings are normally dark, thus we need artificial light, but if we can cut

down on that during daylight hours, we could see a significant improvement.

In terms of CO2 emissions, Denmark has a big plan ahead: achieving the first carbon neutral capital in

the world by 2025. The strategy behind achieving it is described in details in the “Copenhagen

Climate Plan for 2025” and we won’t touch the subject in this paper, as that is a vast subject that

deserves its own, separate discussion. All in one, what Denmark wants is to use renewable energy for

all the energy demand in Copenhagen. The plan focuses on the general, urban overview and the

social aspects of achieving CO2 neutrality, meaning people biking more and improved public

transport and urban lighting solutions. Through its purpose, the climate plan encourages the building

sector to cut down on energy supply that increases CO2 emissions, hence the drastic new

requirements imposed by Danish Building Regulations. They all have a good background, though and

aim towards an achievable goal in the building sector because examples from all over the world show

how intelligent daylighting strategies have saved investors a lot of money from cutting energy

consumptions in buildings.

One examples of good use of daylight to account for energy savings is the Harmony Library in Fort

Collins, Colorado (Figure 16). According to measurements done by the Lighting Research Center of

the Rensselaer Polytechnic Institute, the building achieved a 36% reduction in energy costs solely

through the use of an intelligent daylighting strategy that relies on the use of high clerestories for

deep plan penetration of natural light and diminished possibility of experiencing high brightness, as

well as big windows along the peripheral walls of the library. Moreover, the use of advanced daylight


32

sensors controls the availability of daylight, turning off artificial light for as much as 78% of the

operating hours of the facility. 30

All these design considerations and the approach towards daylighting design, if used correctly and

adjusted to the building scope and climate can be implemented in residential architecture, as well as

in all the other types of buildings. In the following chapter, we will touch upon the subject of existing

technologies that we should use in residential buildings to get natural light in and ultimately achieve

visual comfort of the users and energy costs reductions. Daylight is not just the architect’s response

to visual satisfaction of the users, but also it is universally accepted as a pivotal element to become

more and more energy efficient.

There is a science behind daylight design and it is not as simple as just bringing in natural light

through windows and skylights. A good daylight plan accounts for far more than just windows and

skylights and it’s a mixture of good architectural design planning and available daylighting

technologies, as well as considerations regarding climate and daylight availability. A clever

daylighting strategy takes into account heat gain/and loss, glare, visual comfort and energy savings.

The study of daylighting planning is, thus important, because it is not as simple as it might sound. In

addition to windows and skylights, we should consider plot orientation, surface reflectance and

location of interior partition walls that might obstruct light from penetrating deep plans among other

considerations. After all, a good daylighting system consists of technology and architecture.

In this chapter, we will focus on what are some of the most important and useful daylighting

technologies and systems that we could use in residential architecture to gain a good daylighting

strategy. The chapter is divided into two system approaches and the available technology for each:

side-light and top-light systems. The chapter explains how the systems functions and what is their

feasibility based on my personal analysis and interpretation of data in Denmark’s residential

buildings.

It is important for architects, constructing architects and other professionals of the buildings industry

to understand the importance of implementing daylighting analysis from the conceptual phase of an

architectural space. Daylight simulations can help in creating a good daylighting strategy by

accounting for all necessary precautions and conditions that the designer knows and wants to

implements in the design but they are not mandatory. They are helpful to better understand how

light penetrates the building in order to choose the best daylighting system that works with the

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conditions of the concept. In case daylight simulations are not carried, it is advisable to consider what

is the building scope and desired effect before choosing between the technologies and systems

described below.

The lightshelf is one of the most used side lighting systems available on the market. A lightshelf is

practically a separation placed between the window sill and the window head, thus dividing the

window into two separate areas: the top part becomes a clerestory (a method commonly used in

ancient times to direct natural light into deep plans) and the bottom part becomes the view window.

The lightshelf can either be flat or inclined, in which case it projects light even deeper inside the

room. The lightshelf shouldn’t be confused with an overhang. The overhang has the role to shade the

window, while the lightshelf is used to capture sunlight and redirect it towards the ceiling, which, in

this case, it is recommended to be highly reflective. The amount of light entering a room is regulated

by how deep the lightshelf is. A longer outer protrusion or at least equal to the inner one, normally

offers the best results even in low sun angles that occur during winter. Ideally, lightshelves should be

placed on southern and western facing windows for maximum results (Figure 17). Despite usually

being fixed at a certain angle, newer technology allows to either manually or automatically adjust the

angle of the lightshelf in order to gain all year round benefits.

Feasibility in residential projects: The lightshelft is probably the simplest, cheapest and efficient side

lighting strategy out there and incorporating it into residential projects accounts for a lot of benefits

and also provides shading to avoid overheating and glare discomfort. With the improved glazing

types available on the market, windows can easily cover large proportions of the wall, thus it is easy

to use a lightshelf and still have a comfortable view window available to connect you to the outside.

As regulations ask for a minimum head height of 2.5m, lightshelves can be used at a height of roughly

2 meters, the result being an approximately 500mm high clerestory that can redirect light deep

within the living space, offering a comfortable environment even on winter days. Generally, newer

residential buildings in Denmark do not make use of this innovative, easy solution. The reason might

stand within design considerations to avoid horizontal cuts of the facades, but lightshelves can be

painted to match the window frame or they can be integrated in the design differently as they are

highly customizable.

Prismatic panels have been used before in architecture as diffusers for electrical lighting fixtures, but

they are steadily becoming popular in daylighting strategies. Prismatic panels can be either rigid or

flexible and they come in a variety of shapes and sizes and are generally easy to customize. Best

practice solutions for using prismatic panels are using them as redirecting apparatus in side lighting


34

systems or as facade coverings. Technically wise, prismatic panels are used to refract sunlight at a

range of incident angle and redirect it deep within the room.

Feasibility in residential projects: They might not be as feasible as lightshelves as they are generally

more expensive and could potentially trigger bigger design compromises. Still, in large residential

projects, prismatic panels can act as both shading system against glare and excessive heat and

daylight system if used to cover the entire facade. Prismatic panels used as a facade shell are

generally a better solution for big scale projects and especially for office buildings and schools, where

glare could cause huge discomforts and cooling loads are big. On small scaled projects, using

prismatic panels as reflective material could be a more feasible solution, especially in combination

with lightshelves when the redirecting plane of the latter is covered in a layer of flexible prismatic

panel.

Anidolic systems incorporate the same principle used in solar parabolic concentrators to capture

daylight into a focal point and then redistribute it indoors. 31 Unlike previous systems, anidolic

systems work extremely well in overcast conditions, thus making them a suitable choice for

harvesting natural light indoors in Denmark. This is primarily due to the parabolic mirror of the

system that divides the light from the central point, spreading it evenly. Being highly customizable in

terms of adapting to sun angles, anidolic systems behave very well in all geographical locations.

Simulations carried at LESO-PB (Le Laboratoire d'Energie solaire et de Physique du Bâtiment de

l'EPFL) showed a 70% increase in daylight levels in the subjected test room, deep within the plan.

Feasibility in residential projects: Anidolic systems are an alternative to traditional lightshelves and a

modern replacement to clerestories. Since they work better under overcast sky conditions, they

could account for a far better daylighting strategy in residential buildings in Denmark. The only

considerations are in relations to ceiling heights. If they are not met, lightshelves are the obvious

choice. The system created by D-LITE and illustrated below, incorporates anidolic zenithal collectors

fixed above the window head and an anidolic device mounted inside the room, at ceiling level that

distributes the daylight influx and reduces glare. The system accounts for any thermal issues, by

using double glazing and thermal insulation to avoid thermal bridges. For new projects, it is

necessary to use a light duct (0.65m high and 0.59m long) which means the system needs to be

incorporated within the ceiling. Therefore, the use of anidolic systems is possible in projects designed

to have sufficient head height to meet building regulations and incorporate the system inside the

ceiling. Results are guaranteed, but considerations in regards to using the system in the early stages

of design are essential to successfully incorporate it. (Figure 18 & Figure 19)

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35

A good daylighting strategy doesn’t take into account just ways of bringing in natural light. It is

equally important to consider how to shade the interiors and how to minimize visual discomfort

created by excessive glare. The louver system was created to be used with other side-lighting

systems to offer visual comfort to the inhabitants by filtering the light brought it. Traditional louver

systems were created to guide the natural light deep within the plan, provide sufficient shading in

the summer and enable solar gain during winter and reduce glare, while still allowing views to the

outside. Louver systems can be easily customizable and can be made out of a variety of materials

such as wood and aluminum. With advanced louver systems it’s also possible to separate the whole

aperture of a window into two by keeping the top lamellas of the system in a horizontal position, to

allow natural light to be guided inside (the system works as a clerestory), while the lower part is put

into retro-position for shading. (Figure 20)

Feasibility in residential projects: We cannot compare this system to any of the ones presented

above, because it’s meant to work together with them. We need to understand that even in

Denmark, sometimes we could have too much sun therefore visual comfort could be compromised

by excessive glare. It’s important to consider a louver system because it has advantages both during

summer and winter, accounting for numerous health and economic benefits, while still offering

views of the outside.

Skylights are probably the most popular type of top-lighting system that allows natural light to enter

the buildings in places where side-lighting systems don’t work, either because the openings are too

small or they are too far away from that point. A skylight is a simple opening in the roof and it comes

in a variety of shapes and depths.

Feasibility in residential projects: Skylights are extremely popular in residential buildings especially

under predominantly overcast skies. In Denmark, they are a feature almost every new and renovated

building has and it’s the easiest and most efficient way to bring natural light indoors. Since luminance

at the horizontal plane is generally less abundant than the zenithal portion of the sky, skylights

should be used to illuminate deep plans. Considering that glare discomfort is something we

experience due to side-lighting systems, skylights are a good way to partially minimize side openings,

if a shading system is not considered and still bring sufficient natural light indoors. Velux is one of the

biggest producers of skylights and high consideration for daylight is one their philosophies. They

believe that daylight can increase the value of a home, by bringing in so many benefits. They mostly

invest in advanced glazing and offer a large variety of skylights, light pipes and shading systems.

(Figure 21)


36

An atrium is a large roof opening that brings natural light in the core of a building. Atriums are

especially popular in office and commercial buildings, where the core area of the building is generally

far away from the side openings. In such case, it is far more efficient to use a large atrium than

several, smaller skylights.

Feasibility in residential projects: Normally, atriums are used in large scale projects, where plans are

especially big and the core area is poorly daylit. Still, efficiently dimensioned atriums can be adapted

for residential use especially for apartment buildings. Ideally atriums shouldn’t be used inside

apartments, to minimize heat loss, but they could be a central design feature in hallways or as inner

courtyard coverings. (Figure 22)

A light pipe is an innovative top-lighting system that is designed to bring natural light into the lower

floors of a multistory building. A traditional light pipe is made out of 3 distinct components: a

collector, a transport and a distribution system. Just as any other system, light pipes come in

different sizes and shapes and they can be customized to adapt to certain requirements. The system

that collects the light is extremely versatile and can be made out of the following materials:

polycarbonate dome, solar tracking mirror, optical lens or a light deflector such as a laser cut panel.32

Moreover, hollow prism light guides and fiber optics can be used. The variety of light pipes is so big,

it is generally advisable to consult manufacturer specifications to understand which one is more

suitable for certain needs. Considerations in regards to the material are normally closely related to

how deep the light pipe needs to illuminate.

Feasibility in residential projects: Light pipes are ideal to bring natural light into narrow rooms, such

as bathrooms (Figure 22). Furthermore, light pipes take up a small part of the roof and bring in a lot

of natural light in those rooms where there is no side light coming in (Figure 23). Light pipes that use

prism light guides can illuminate deep down into a multistory building, especially in the corridors of

apartment buildings, as seen in Figure 24 making them a feasible solutions for daylight illumination in

residential projects with minimal heat loss and no glare. Best used would be in corridors. Normally,

corridors are at the core section of a residential building, making them almost entirely dependent on

artificial light. By using a light pipe in those areas, we could potentially stop using electrical light

during the day, thus saving a lot in energy costs.

Whether it is side-lighting or top-lighting we are using or a combination of both, it is critical to

understand that a good daylighting plan accounts for more than just bringing in natural light. Glare

discomfort and heat loss are important when choosing the best systems and normally, a combination

32 (Boubekri, 2014) pp. 85


37

of technologies can create the best result, especially under overcast skies. User satisfaction and

meeting energy demands are extremely important considerations we, us constructing architects have

to take into account to meet regulations and increase the value of the buildings we are designing.

In Danish architecture, daylight is very important, but this doesn’t necessarily imply that it is brought

indoors through clever ways that account for more benefits than disadvantages. As mentioned

earlier in this paper, a good daylighting strategy means more than just making as many openings as

possible. For that, daylight is brought into question in Building Regulations under chapter 6.5 Lighting

conditions. The regulations I am citing and analysis in this chapter were issued in 2010. The ones

from 2015 are at the time of writing this paper, still in the making. This chapter discusses just the

regulations related to daylight that are relevant for residential projects.

6.5.2(1) (…) habitable rooms must have sufficient daylight for the rooms to be well lit. Windows must

be made, located and, where appropriate, screened such that sunlight through them does not cause

overheating in the rooms, and such that nuisance from direct solar heat gain is avoided.

Other excerpts from BR10 chapter 6.5:

I. If the light transmittance of the window is less than 0.75 it may be necessary to increase the

area of the window system.

II. If the location of the building means that the surroundings prevent daylight from reaching

the windows to a significant degree, the proportion of windows must be increased

accordingly.

III. Daylight may similarly be deemed to be adequate when calculation or measurement can

demonstrate that there is a daylight factor of 2% in the workplaces.

IV. Where external shading elements vary, such as broadleaf trees, the focus should be on

conditions in the winter months when daylight levels are generally at their lowest.

V. Unless the actual or planned surface reflectance is known, the following values may be

assumed: ceiling 0.7, walls 0.4 and floors 0.1.

6.5.2(2) (…) habitable rooms that are primarily illuminated via roof lights must always be fitted with

windows in walls to provide views of the surroundings.

The regulations in cause point out some of the most important and already discussed factors that

constructing architects and architects have to consider from the early stages of design. It is easier to

implement these considerations early in the design process to make sure no compromises are

needed later, that could come at both economic and design costs. The purpose of chapter 6.5 is to

achieve visual comfort, without looking at the energy efficiency considerations. In order to meet the


38

regulations for amount of daylight available in habitable rooms, it is important to use calculations to

find out the daylight factor. Moreover, daylight simulations can provide the answer as to where and

potentially how to increase the daylight factor in a room. Minimum, a daylight factor33of 2% is

required in habitable rooms, as stated in the excerpts from BR10 cited above.

Daylight planning is strictly connected to local climate conditions. Since this paper is delimited to

Denmark (mentioning that it might be possible, at your own risk and analysis to use parts of this

research in countries with a similar climate) we will discuss some important aspects of Denmark’s

characteristic climate conditions. When considering a good daylight strategy, it’s important to use

accurate climate data to gain the best insight into the problem and understand how to best tackle it.

Denmark is famous for its gloomy weather. With a predominantly overcast sky from autumn to

spring, you can go days without seeing any sunlight. Still, zenithal light is plentiful to supply the

necessary natural light for our bodies to function properly and our buildings to be illuminated

accordingly. Gaining a better insight into local daylight conditions, could aid us in choosing the best

systems when creating the daylighting strategy. (Table 3)

Table 3 Below: Daylight statistics for Copenhagen

(Courtesy: http://www.copenhagen.climatemps.com/sunlight.php)

33 The daylight factor is the result of Einternal divided to Eexternal multiplied to 100%, where E is the illuminance (lux). In de Place Hansen, E., 2012. Guidelines on Building Regulations 2010. Hørsholm: Danish Building Research Institute, Aalborg University, pp.Chapter 6.5 Lighting Conditions

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

Average sunlight

hours/day

01:09 01:56 03:48 05:22 07:54 08:10 07:42 06:40 05:14 02:48 01:08 00:36 04:23

Average daylight hours & minutes

/day

07:44 09:33 11:47 14:10 16:16 17:26 16:54 15:02 12:43 10:20 08:15 07:08 12:00

Sunny and (cloudy) daylight

hours (%)

16 (84)

21 (79)

33 (67)

39 (61)

49 (51)

48 (52)

46 (54)

45 (55)

42 (58)

28 (72)

14 (86)

9 (91)

37 (63)

Sun altitude at solar noon on the 21

st

day (°)

14.5 23.8 34.6 46.2 54.5 57.8 54.7 46.4 35 23.5 14.4 11 34.7


39

We can observe in the annual average that the sky is predominantly overcast, 37% to 63% and that in

May and June we experience the most sunlight hours, while in December the least. With these

statistics, we can conclude that a daylighting strategy for buildings in Denmark require good

adaptability all year around, meaning that it is possible to experience moments when we can either

have too much or too little daylight indoors. For this, a prior analysis of location climate data needs

to be undertaken, ideally, in form of simulations or calculations, to gain knowledge of how to best

approach a good daylighting strategy from the early stages of design. This lands under key

considerations that constructing architects and architects need to highlight in the design approach.

Without such considerations, the resulting daylight planning could be problematic, as it might not fit

with daylight availability of chosen location and year round climate conditions.


40

The method used to analyze the data acquired through interviews is a combination of the deductive

34and inductive35 methods. The reason behind addressing the qualitative data in such a manner is

given by some of the questions that involve hands-on personal experience of the persons

interviewed, therefore creating data for which I do not expect to impose any pre-read and analyzed

theory. Furthermore, the main goal of the interviews was to see different perspectives and

perceptions of the subject in cause, and the theory that I already have can aid in creating a final

recommendation and personal interpretation, but it’s not meant to bias certain answers that are

considered pivotal to the conclusion, because of their original source that was able to provide

information from personal experience.

The interview has a total of 16 questions and the full transcripts are found in Appendix II. Since the

interviews are quite long, spanning well over 6 pages in length, I have chosen to attach them as

appendices and use quotes and meaningful observations as a way of discussing them. The answers

are anonymous, but the professions of the individuals are mentioned to highlight the differences in

perception that come with the profession. The analysis touches on every question and separates into

specifics that are milestones towards answering the problem.

Furthermore, the analysis is carried as a journey that discovers and pin-points pivotal elements

associated with the different research questions raised in the introduction of this paper as means to

answer them as clearly and as efficiently as possible. The whole process that develops from the

problem has been mind-mapped36 in the beginning of chapter 4.2 Interview data analysis. The

graphic was done after the analysis was finished and the data from the interviews was extracted and

interpreted, therefore no new information apart from the one analyzed is presented in it. The

graphic displays an effective summary of the answers brought to the problem and research questions

as findings and recommendations which are further explained and largely discussed. Due to the large

amount of text, it is recommended to zoom in on the page.

The analysis is concluded by overall recommendations that are meant to pave the way towards the

final conclusion in chapter 5. No new information is to be added after this point.

34 Deductive approaches involve using a structure or predetermined framework to analyze data. Essentially, the researcher imposes their own structure or theories on the data and then uses these to analyze the interview transcripts. Gill, P., 2015. Analyzing and presenting qualitative data. [online] Academia.edu 35 Inductive approach involves analyzing data with little or no predetermined theory, structure or framework and uses the actual data itself to derive the structure of analysis. Gill, P., 2015. Analyzing and presenting qualitative data. [online] Academia.edu 36 XMind Mind-mapping software (trial version), courtesy of XMind LTD


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Interviewees: A: Lighting Design Student | B: BIM Manager | C: Computational Design Specialist

This chapter contains the analysis and discussion of the answers to the first secondary research

question: What are the benefits behind designing with daylight?

Question 1: The interview stars with the question regarding visual comfort and energy efficiency and

which one is the most important. We can see from the transcripts that the majority of answers

(persons B and C) say it is not possible to pin point which one is the most important, because

“daylight is a complex thing in architecture” and “it depends on the project (…) which one you would

choose to put more importance to”. On the other hand, seen from the lighting designer’s perspective,

visual comfort is more important.

This is one of those cases when daylight is a subjective factor, varying in importance from project to

project. The question is meant to see a personal and professional opinion that is generally based on

previous experiences, thus it cannot be consider a universal true and cannot be applied to all

residential projects. On the other hand, what we can deduct from these answers is that it is

incredibly important to consider daylighting as a contributing factor for both visual comfort and

energy efficiency and understand that a good planning would involve balancing up both, without

overlooking one for the other.

Question 2: When asked about the importance of a good daylighting plan of buildings in Denmark

and the possibility of it being overlooked, all participants consider that daylight is very important in

architecture and especially in a country that experiences months with little solar activity. Moreover,

we see that Danish architects pride themselves in being good at integrating daylight into their work

methodology and would normally go to great extents to make sure that daylighting is well integrated

into the architectural concept. On the other hand, certain other factors related particularly to the

project in cause, may cause daylight to be overlooked.

The Danish architecture culture is generally informed about the importance of implementing daylight

into architectural concepts, but external or internal related factors specific to the project could

possibly make daylight a factor that could be overlooked in favor of other considerations. Still,

daylight holds an important place since there are regulations that impose minimum standards.

Question 3: On the third question, persons A and B consider that the psychological and physical

benefits of daylight are taken into account when designing a new concept, while person C suggests

that on most projects, it is not. However, in places such as hospitals and office spaces, research into

daylight is usually used to meet the 2, 3% daylight factor requirements.


43

I think that the mind-set associated to daylight use in residential architecture focuses more on the

energy related side, primarily because of strict regulations regarding energy supply, whilst the visual

comfort part is dealt with through achieving the necessary minimum daylight factor. This doesn’t

always imply that a good strategy was used, that would minimize glare discomfort and overheating.

A sustainable living environment doesn’t just constitute of efficient use of materials and reduction in

CO2 emissions. A sustainable living environment needs to also consider the end user.

Conclusion: The benefits behind designing with daylight are plentiful, from health benefits

(remember that daylight is the key to our well-being) to economic benefits, that involve both energy

savings and user productivity. Designing with daylight is a pivotal step towards green architecture

that should be a symbiosis of environmentally friendly solutions and human friendly conditions. After

all, we design and plan for the end users and their satisfaction should be a philosophy in every

company.

This chapter contains the analysis and discussion of the answers to the second secondary research

question: What are the issues and key considerations that we need to consider in order to achieve a

strong daylight strategy from the early stages of design in residential buildings in Denmark?

Question 4: The interviewees unanimously consider that daylight should be a primary factor from the

early stages of design, because that is where most of the major design decisions are being made and

daylight planning, if used accordingly, would be one of those factors that influence the geometry,

openings, plot orientation and early on set façade systems. The BIM manager mentions that his job

involves introducing daylight simulations into the early work methodology of architects to avoid later

surprises - such as not complying with the regulations.

It is obvious that early on set considerations for daylight planning are important, not just because

daylight is one of the most important factors influencing the concept, but also because not

understanding the repercussions associated to late or poor implementation of daylight and not

complying with daylight regulations could result in remodeling and re-thinking concepts, all of these

at high costs. Poor handling of available resources and research into proper daylighting, together

with misunderstandings regarding what a good daylight planning consists of, can cause serious

problems for both big and small companies. No client would like to pay extra for errors and poor

judgement of professionals that exceed budgets by making mistakes that could be avoided. A lack of

training in the field is potentially a cause, especially in smaller companies that do not assign a

specialized team responsible for introducing and implementing early parameters into the working

culture. Luckily, over the course of recent years, BIM has gained importance in architecture

companies in Denmark. A BIM team is normally responsible for introducing advanced modelling


44

software, as well as simulations that would enable a better understanding and use of natural light. As

long as efforts continue to be made in the private sector, early on set simulations shouldn’t be a

mystery even for small companies in 10 years from now.

Question 5: The following question, regarding information acquired through personal experience

about early consideration of daylight planning, the interviewees consider that all architects have tacit

knowledge about natural light. This type of knowledge, created through years of experience, guide

the architects towards making choices in relation to massing, room height, room depth and number

of openings. It is when we need to build something abroad, that we encounter problems since the

knowledge that Danish architects have is mostly restricted to the geographical area of Northern

Europe, where climatic data is similar. Moreover, as we can deduct from the answers given so far,

the perception of daylight varies from profession to profession. Sometimes, this alone can be an

issue that needs to be taken into account.

We understand that the concept of early simulations is rather new in the architectural practice, so

architects still mostly rely on their tacit knowledge gained after years of experience, which doesn’t

always take into account all the sides of what good daylight planning is. A misunderstanding here,

followed by poor research and lack of skills for simulations, form a triangle that could very well result

in a strategy that simply doesn’t work, even if the daylight factor percentage is achieved. In the early

phases is where architects have free hand to play with masses, change geometry and simulations,

even though they aren’t mandatory, would shed light on the problematic areas of the building.

Moreover, it is easier to correct them by trying different alternatives, as suggested in chapter 3.6.

Questions 6 and 7: The interviews show that mostly, architects are willing to do volumetric changes,

as well as other changes in parameters of the building in the early stages of design to facilitate

natural light availability. As expected, later in the project it is a lot harder to go back to these

parameters and adjust them.

Another issue that needs to be taken into account is communication; either between working

professionals or most importantly between architect and client. Generally, clients are not specialized

within the architectural field. Therefore their demands can sometimes be unfounded. It is the

architect’s or company’s job to talk to the client and explain why certain parameters are more

important than the others. As working professionals, we cannot expect to talk technicalities with

clients that do not activate in the field. However, a client that values his/hers money would

understand that everyone is good as something and their expertise could be crucial to the project

they want to invest in. A good project can only be achieved through proper communication. It is also

that sometimes, design integrity represents an issue. Even though the people I interviewed generally

think that Danish architects pride themselves for being design conscious about daylight planning,


45

when we look over the previous issues that we identified, one of them being lack of proper training

and integration of knowledge into the design philosophy of the company, some architects could be

inflexible, simply because they rely solely on tacit knowledge or because they value more some other

early onset parameters of design. We can conclude that all these issues and considerations come

hand in hand.

Question 8: The answers to this question lead us towards some of the key considerations that

specialists need to consider in the early stages of design, such as window location, South massing,

less deep floor plans and bigger room heights. It is here that we can identify more of the key

considerations that would answer part of our research question, apart from those that form issues

and are part of the general company philosophy or the one integrated into the architectural practice.

It is important to analyze each early parameter in close connection with specialists. Using external

consultants is a solution, especially for smaller companies, which are not as well diversified in terms

of staff backgrounds as bigger ones.

Moreover, it is advisable that the people in charge prioritize early design parameters that could

enable a better spread of natural light indoors. This step should be taken as a starting point when

working on a new concept. The tacit knowledge that we have, combined with client requirements,

plot conditions (including obstructions, sunlight availability, etc.) are key considerations in the design

process that should be valued throughout the entire project phases. These considerations shape the

parameters that vary from project to project. For residential purposes, the rooms that require the

most light are those where visual comfort is more need (study room, proximity to desk placement

and office room). Room heights should be designed to a standard minimum of 2.5m, but the taller

the room, the better it is in terms of visual comfort. The down side of high ceilings is heat loss. Also,

deep floor plans are another factor that comes into analysis early in the concept and schematic

phases.

Questions 9 and 10: Daylight simulations do have limitations. Traditional ones especially, make it

harder to speed up the process. Moreover, with traditional daylight simulation tools, it is possible to

only investigate a very specific area, that of daylight. Sometimes, correlation between parameters is

extremely important, therefore more advanced software such as Rhino (with Grasshoper coding) and

BIM simulations could account for far better results. Having to remodel in traditional simulation tools

is redundant work and you run the risk that “the remodeled version is not fully compatible with the

actual model that you do for documentation”. Having models that do not match causes errors in the

simulation that could result in taking the wrong decision that wouldn’t normally work. Of course, big

changes would be easy to spot, but carrying redundant work is both costly and inefficient, potentially

resulting in worker frustration and not achieving important milestones. Still, as the BIM Manager

highlights, BIM simulations aren’t that great for the moment and further development in the area is


46

needed before traditional software can be discarded from general use in the architectural practice.

We also need to consider that early stages of design normally don’t have a BIM model, since that one

usually comes into use later in the phases. With that in mind, even though they could become

extremely performant in the future, more work towards the massing options in BIM tools needs to

be undertaken before professionals start using them from the very beginning of a project.

Question 11: This question forms a very important element in this paper. We can see that

professionals highlight different issues that they observed or experienced throughout their carriers.

For the Lighting Designer, it is important to use the window as a daylighting tool and not just “as an

exotic feature” that some architects make it into. On the other hand, the BIM manager pinpoints

something that could come as a surprise: overexposing of interiors in Danish architecture. The

general conception is that there is not so much sun in Denmark. Therefore, it’s quite hard or even

impossible to have too much indoors. But recent architecture in the country has experienced a great

increase of façade openings: full glass facades are not a novelty anymore. Everywhere you look

around you are likely to see beautiful architecture that features overall glass facades. As it has been

mentioned several times, daylight planning doesn’t mean creating as many openings and

implementing systems and technologies that just facilitate the penetration of natural light indoors. A

good strategy takes into account shading.

A comfortable indoor environment minimizes glare and overheating. The conclusion is that daylight

simulations are probably going to aid into solving this issue. Simulations can tell how the interior

behaves after the façade has been covered in a shading filter, or after a louver system is integrated

into it. Simple, tacit knowledge is not enough to understand and account for all possible options that

are available on the market. Moreover, knowledge and training of staff can be costly, but on the

long run, it improves the quality of a company’s projects. You cannot expect for professionals to keep

up with the latest research just by themselves. Companies that pride themselves for being

professionals and offering the best services have to invest in their employees.

Conclusion: The first step towards improvement is to understand what are the issues that staggered

developed up until that point. In daylight planning, we can see from the data collected, there are

some repeating factors among which the most predominant ones are: different perspectives across

professions, lack of knowledge and interest at company level, slow development of simulation

integration, miscommunication and overexposing in recent Danish architecture. Tackling these issues

can be a monumental task, especially in smaller companies that are far behind with BIM

implementation. Previous experience showed me that a lot of small companies still use 2D software

and the process of implementing BIM is either absent at all or incredibly slow, mostly because costs

associated to the creation of BIM models is higher than that of CAD ones. Moreover, from the

interviews, we also understand that current regulations regarding daylight are way too rigid and


47

deviating from them can cause problems with overexposing and overheating the building. This is a

big milestone, because in Denmark, legislations for building are very important and dispensations

aren’t always easy to obtain, especially in an area where Danish legislators think they have the

correct answer. However, to speed up the process, more awareness needs to be spread so that

smaller companies can learn from those that are already far ahead with simulation implementation.

Conferences, dialogue and share of knowledge between professionals of the industry can aid the

tedious and long process that is required to better understand the importance of having daylight at

the top of the parameter list from the early stages of design, as well as working towards creating a

philosophy in the architectural practice that daylight planning is more than just various ways of

bringing in natural light.

This chapter contains the analysis and discussion of the answers to the third secondary research

question: How to create a strong and efficient daylighting strategy in Denmark´s residential buildings

after understanding the issues and key considerations we need to face in order to achieve economic

benefits and visual comfort?

The last five questions of the interviews were directed towards findings out what are the steps

necessary for creating a strong and efficient daylighting strategy for Denmark’ residential buildings.

After understanding the issues and key considerations that companies have to work with, this

chapter includes recommendations for every project phase. The purpose of this paper was not just to

pinpoint what is important in the early stages, but from the early stages, because a daylight planning

needs to be worked on all throughout the design process and even after occupancy.

Questions 12, 13, 14 and 15 show that the majority of the persons interviewed agree that daylight

strategies should vary according to the building scope: there is a big difference between regulations

for residential and those for a hospital or an office space. Nevertheless, the importance of natural

light into homes is indisputable. Moreover, persons A, B, and C consider that a good strategy

involves help from both authorities (that need to work towards achieving manageable and flexible

regulations, which would account for better results in the end) and use of advanced glazing – “I’ve

heard that now they are trying to test six layered glass”. I would like to add that lightshelves or

anidolic systems would work best to bring light in big rooms, such as the living room, while top-

lighting systems, such as light pipes or skylights, could increase the comfort level in bathrooms,

kitchens and bedrooms. It’s important not to forget that these systems should never compromise the

views to the exterior.

Colors and materials play a very important role as well. There is an entire research behind which

color works the best in every type of room. It is known that color influences mood. Green would


48

work best in a bedroom, because it means health and tranquility and helps the brain relax. Yellow, on

the other hand, is a color that gives energy and increases metabolism, so its use would be best in

kitchens. Blue is the most productive of colors and using it in places where you need to study or work

makes the best out of it. (Figure 25) Materials, like colors, have a pivotal role in daylight planning.

Lightshelves direct natural light indoors towards the ceiling. A high reflectance in the material used

combined with a light color, that best reflects light, means that the angle of penetration would be

bigger, thus natural light can reach in deeper areas of the plan that would, otherwise, be dimmer.

Proper daylight implementation in residential projects across Denmark needs to start at company

level. The philosophy and understanding of early parameters is of great importance if useful results

need to be achieved. The first obvious step is using external advisors, such as lighting specialists. The

new education at Aalborg University in Lighting Design brings a lot of fresh professionals to the

industry that work towards optimizing the use of daylight and artificial light in the architecture of

Denmark. With a Scandinavian approach to design and light, their expertise is not just useful but in

line with current standards.

Furthermore, an ongoing communication procedure with the authorities would be benefic for the

entire industry. We’ve understood from professionals activating in the industry that sometimes,

regulations can be too rigid. Legislations impose increased glazing areas when obstructions on the

building site prevent sufficient sun exposure. Increased glazing areas mean heath loss and

sometimes, too much light can be brought in, if the glazing is not covered in a filter that aids cooling

and shading of the interior. Therefore, I consider a feedback system between private companies and

legislators would result in speeding up the time it takes to reach that point where our buildings are

both comfortable and energy efficient.

In the concept and schematic design phases, architects, constructing architects and external advisors

need to cooperate to better integrate the early parameters. Each one of these parameters plays an

important role and will eventually shape the way the massing is done. Daylight is strictly connected

to geography data and plot conditions. Analysis and studies need to be carried to a maximum in this

stage. Carrying them later could mean that geometry might be affected. Careful attention needs to

be given to internal walls, partition walls and furniture. Internal obstructions could affect the results.

It is here that specialists need to start considering what type of lighting strategy they want to

incorporate to avoid mismatches with system requirements that could later affect, for example,

room heights. Furthermore, at this step, materials and colors can be recommended. Studies should

be undertaken in connection with daylight simulations on how interior finishes behave under natural

light. These are not final materials, but it’s good to backup findings with studies for later use.


49

Maybe the most important aspect in this stage is how the façade is developed. Side-lighting is

generally the dominant approach. Massing of the façade needs to take into account the orientation

of the building as well as type of glazing, filter use or other technologies. In chapter 3.6 we discussed

the feasibility of some technologies that would work in residential buildings. The plus and minuses

are discussed and compared. Every project is different so specialists need to work around specifics.

Moreover, it is in this point when decisions towards final material recommendations are made. A set

of well carried studies could potentially speed up the process when discussing options with the

client. It’s always good to back up your findings with simulations and studies that highlight the way

certain areas of the building would behave under different conditions. A building should work at a

high level in both winter and summer.

Last but not least, certain project specifics could prevent the use of natural light in certain areas of

the building. Mixing up the use of natural light with artificial light should be done in a clever way. At

this stage, it’s still important to keep close connection to specialists in lighting.

At this phase, the final materials are chosen for the preparation of construction drawings. As the

building progresses, little changes should affect the way daylight as a parameter has been

implemented to this point. It is also here that contractors can propose good prices for automated

systems that adjust according to natural light availability. Such systems would certainly save money

in terms of energy costs. An automatic daylight system is perfect in corridors of apartment buildings.

It is also advisable to pinpoint the specifics in regards to daylight planning, so that contractors do not

overlook its importance as a parameter.

Daylight planning doesn’t stop, as most would think, after the building is handed over. On the

contrary, in order to understand how strategies work, I would recommend that user satisfaction

surveys are carried. Some things might look and sound better on paper than they actually do in

reality. Throughout the history of architecture, we have learned from our own mistakes. As we’ve

seen in chapter 3.3, in the past, architects would improve considerably the previous available

knowledge. We are still doing it to this day, therefore I find that hands on opinions from residents of

the building could spark new research and studies into what went right or wrong and how it can be

avoided in the future.

Furthermore, post-occupancy daylight planning involves maintenance of the systems and

professional feedback of equipment performance. Architectural companies should work hand-in-

hand with glass manufacturers. Velux has a very good feedback system with its clients, enabling it to


50

improve the products considerably based on real opinions and expertise. They can be used as

pioneers in the field and smaller manufacturers can use their client communication philosophy as a

way to improve.

Last but not least, as the building reaches 20, 30 years milestones, we have to continue upgrading it

to meet new energy demands. Just like the renovation of old buildings in Denmark in the ‘60’s and

‘70’s, in 30 years from now, what we build today might not be as sustainable.

The interview data proved to be a very important last step towards accomplishing the goal of this

paper. By collecting useful, real information from professionals of the industry in Denmark, we have

managed to pin-point some of the things that are, otherwise hard to achieve in any other way. I

consider that the findings associated with these interviews, together with my experience and

observations throughout the time I have researched, have shaped a final understanding of why this is

useful for the profession and for the entire culture of building in Denmark with daylight.


51

2015 is a very interesting year for daylight – increasingly gaining more attention worldwide, natural

light in architecture is becoming a stand-alone pivotal parameter. Furthermore, Denmark is

especially involved in the whole energy efficient architecture and user satisfaction philosophy. With

that in mind, this research is interestingly placed at the peak importance level of daylight planning

implementation, but still, somehow in the process of understanding the most efficient way of

achieving the existing criterion in reality.

Danish architecture and generally, the Scandinavian way of designing buildings work using tacit

knowledge of how daylight should be included into construction. Specialists, particularly architects,

pride themselves for going to extreme extents to bring natural light indoors, but it is here that the

majority of the problems have a starting point. As leading specialists of the industry, architects and

construction architects alike, find themselves at the point where further development of existing

technologies and a constant improvement of the working methodology within the architectural

practice are much needed – as energy supply requirements become less and less flexible, research

into innovative, new products is a pivotal milestone. This has been proved within the research

especially through the use of the hands on experience of professionals of the industry in Denmark – a

constant feedback system with the authorities in charge of legislations is a recommendation that

could potentially speed up the tedious process behind adjusting regulations to be less rigid and allow

for far more complexity in the design approach parameters and considerations than what we see at

the moment. Furthermore, possible new inventions could minimize one of the biggest problems of

contemporary Danish architecture: overexposing of interiors to natural light that causes visual

discomfort and overheating.

The weighting question of this paper, that seeks to pin point specific issues and key considerations

that arise from within the reality of the current state of the industry, leads us to the conclusion that

recommendations towards investments and shifts in the current learning methodologies at company

level - which should be focused on implementing the knowledge in relation to daylight planning from

the early stages of design through creation of specialized teams and close cooperation with

consultants - are where we normally need to start. They could, potentially create a uniformity in the

mind-set behind perception of daylight as an important parameter across architectural professions

and bridge the existing tacit knowledge to what modern technological advancements can offer –

such as advanced simulation tools. Furthermore, by inter-company communication, conferences and

seminars, important developments can be achieved as a general industry standard in both small and

big private companies.


52

By connecting the issues and key considerations, the clear path towards implementation of daylight

as an early onset parameter in residential buildings can be achieved throughout the project phases

through careful attention given to all sub-factors involved in a clever daylight planning: position,

early massing with South orientation emphasis of big openings, number and placement of openings

in connection with realistic geographical data and weather statistics, choice of feasible technologies

and systems that enable the maximum use of natural light into habitable rooms without causing

visual distress, prioritized planning of natural light availability according to room scope, careful

selection of materials with high reflectance capabilities, choice of colors and a use-friendly,

sustainable approach to mixing artificial light with natural light when and if needed. It is, though,

important to analyze the percentage of importance allocated to daylight as a parameter according to

projects specifics.

Daylight is a very complex parameter in architecture – with increasing international attention and

inflexible planning standards, traditional working methods for including natural light from the early

stages of design (such as simple plot orientation and number and placement of openings) cannot

keep up with the demands. The problems arise as early as company philosophy, mentalities and

inflexibility in the line of work and continue outside the private sector (example being the legislations

that do not account for too much deviation), to such extents that existing technologies need an

ongoing development as, especially energy related demands are expected to reach limits by 2025

that today, seem slightly improbable. Luckily, Denmark is a country that keeps sustainability high on

the general agenda, and daylight occupies one of the front spots towards sustainability.

Daylight is a complex parameter in architecture. Throughout this paper we highlighted its benefits,

technologies and ways of implementing it. In the future, Denmark seeks to become CO2 neutral and

works towards creating green architecture. I consider that an ongoing development in the field is not

just necessary but pivotal. For some, the Danish tradition of good use of natural light in architecture

might seem enough, but the tacit knowledge, passed over and over from generation to generation of

architects cannot keep up with the current standards.

2015 is the year of the daylight. Now, more than ever, daylight plays such an important role. We now

better understand its healing benefits and how to use it to facilitate energy supply reductions. With a

bit of luck and cooperation, in 10 years from now, we will stop relying on tacit knowledge and

instead, overcome the issues and boundaries imposed now by the lack of philosophy uniformity in

the architectural practice of Denmark.


53

Now, looking back at the last two months of research, I am extremely confident that I made a good

choice by choosing to focus on a subject that long sparked an interested in me and that is of

importance both to the constructing architect profession and to the building industry of Denmark. I

find its relevance to my profession to stand particularly in the approach of implementing daylight

into the early onset parameters – simulations, as well as in the company approach of spreading

knowledge through cooperation. As leading professionals in software technology in Denmark and as

mediators between the architects and the engineers, constructing architects play a pivotal role in

implementation of daylight planning from the early stages.

Through theory based data and empirical data, I managed to gather an important amount of

knowledge. Furthermore, personal opinions and observations were key elements in this research. I

am glad I was able to form own perspectives after spending 3 years in the education and during my

professional placement at BIG architects.

Concluding, I am confident that I managed to achieve my personal milestones and expectations and

that this paper would form the basis for my future development and my aspirations. I hope that in

the future I will be able to bring a more significant contribution to the field of daylight in

architecture, as I am planning to invest more time and curiosity into this area of research.


54

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Research Institute, Aalborg University, pp.Chapter 6.5 Lighting Conditions

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E., 2000. Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is

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In order to preserve the quality of the pictures and facilitate an easy understanding without taking up

entire pages and create disruptions in the text, I have chosen to put the figures as appendices. Every

figure is followed by a comprehensive description.

Figure 1 - Clerestory used in Ancient Egypt - Hypostyle Hall (Courtesy of: http://web0.memphis.edu)

Figure 2 - 3D rendition of a clerestory and roof

construction in the Hypostyle Hall - Ancient Egypt

(Courtesy of: http://web0.memphis.edu)


57

Figure 3 Ancient Egyptian homes featuring limited openings to protect their inhabitants from the harsh desert

climate. (Courtesy of: http://factsanddetails.com)

Figure 4 City plan of Olynthus and example of Greek house

- parallel and perpendicular streets running east-west, and

houses with southern exposure. Building heights were

limited to give all residents enough natural light and avoid

excessive shading.

(Courtesy of: http://www.lowtechmagazine.com)


58

Figure 5 The central oculus in the Pantheon 126AD. (Courtesy of: http://architecturerevived.blogspot.dk )

Figure 6 Over ninety windows punctured at the base of the dome, give it a weightless appearance and

illuminate the intricating gilded mosaic of the walls. In the back, smaller, half domes, were designed with the

same principle of weightlessness. (Courtesy of: http://msjenniferboone.hubpages.com/hub/Byzantine-vs-

Roman-Hagia-Sophia-vs-Pantheon)


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Figure 7 On the right: Diagram showing the use of

flying buttresses for support of the load bearing

structure. For illumination, clerestories and small

openings in the triforium were preferred in spaces

with high ceilings such as cathedrals and

churches. (Courtesy: http://elizabethgatlin.com)

Figure 8 On the left: North Rose window and stained glass at Chartres

Cathedral, France (c. 1220) (Courtesy of: http://www.wga.hu)

Figure 9 Inside Michelangelo’s dome

of St. Peter’s Basilica in Rome. 16

windows puncture the base of the

dome, typical of Michelangelo’s style

(Courtesy of: http://mstecker.com/)


60

Figure 10 Above, interior of Johann Balthasar Neumann’s Vierzehnheiligen Bad Staffelstein-Bamberg Church

(1772). Predominantly white and gold interiors, associated with the divine interpretation of the time, lit by a

series of 56 windows of uncoloured glass. The association creates a dramatic and sumptuous light in the

interior. (Courtesy of: http://culturemechanism.blogspot.dk/)


61

(continuation of previous figure) On the left, The Hall

of Mirrors at the Amalienburg Pavilion in Munich

(1739), designed by Francois Cuvillies - mirrors line the

white and golden interior to create a widen spatial

spectrum for the viewer. “The room is regarded as one

of the quintessential spaces of Rococo.” (Courtesy of:

www.tripadvisor.com)

Figure 11 A total of 9 vaults, carried by slim columns make up the roof of the Henri Labrouste’s National

Library in Paris. The vaults are daylit by huge roof lights. The correlation between the newly developed

engineering solutions and the use of daylight is exemplified in this masterpiece of industrial architecture.

(Courtesy of: http://www.architecturaldigest.com/ and https://www.flickr.com)


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Figure 12 Viipuri Library in Viborg,Denmark by Alvar Aalto. The main atrium lit by roof lights.

(Courtesy of: http://www.alvaraalto.fi/)


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Figure 13 Ronchamp by Le Corbusier – above: interior of the church; below: canon à lumière, lighting

technique used by Le Corbusier to bring deep, recessed light into his interiors. (Courtesy of:

http://flickrhivemind.net/Tags/chapelle,lecorbusier/Interesting)


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Figure 14 Kiasma Museum, Helsinki (1998) by Stephen Holl - huge, overhead daylight system illuminates the

interior, creating a diffuse and neutral light against the white concrete walls. Materials and neutral colors are a

key feature of Scandinavian architecture. (Courtesy of: http://architectuul.com)

Figure 15 Denmark has experienced important energy usage cuts in the past few years. The pie charts show

the percentage of energy usage of household appliances in residential buildings. Lighting accounts for the

second most energy consuming appliance in Danish households. (Courtesy of: Danish Energy Association,

“Danish Electricity Supply ‘08 - Statistical survey”, 2008)


65

Figure 16 The use of clerestories and big, side

openings, allow plenty of light to penetrate the

deep plan of the Harmony Library in Fort Collins,

Colorado (Courtesy of: http://images.nrel.gov/)

Figure 17 On the left, difference in sun angle between winter and summer. In both cases, the use of

lightshelves maximizes the indoor penetration of natural light. On the right, principle of how lightshelves

function: natural light hits the top side of the lightshelf and is then directed towards the ceiling, that reflects

the light deep within the space. (Courtesy of: https://churchoperations.wordpress.com &

http://www.lighthome.com.au/ )


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Figure 19 Section through room using an anidolic system for illumination. Anidolic systems can bring light

deep within the room even on overcast skies making them a suitable solution for Denmark or other countries

at high latitudes. (Courtesy of: http://spie.org/)

Figure 18 Anidolic system with

light duct by D-LINE. (Courtesy of:

http://d-lite.org)


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Figure 20 “Daytec” Louver system developed by Durlum GmbH that combines sun protection and daylight

control of the room. You can see the position of the top and bottom lamellas. This system has a lot of benefits

including good lighting in deep plans, adjustability, reduced glare, sun protection and visibility to the outside

and low heat input. (Courtesy of: http://www.durlum.de/E/02_licht/pdf/tageslichtsysteme/DAYTEC.PDF)

Figure 21 Velux are the leading professionals when it comes to daylight planning. Illustrated above several

types of roof openings they provide. (Courtesy of: velux.com)


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Figure 22 Apartment building complex by O’Dwyer and Associates Architects - central feature of the inner

courtyard is the big atrium that provides plenty of daylight, while still acting as weather protection. (Courtesy

of: O’Dwyer and Associates Architects)

Figure 23 Rendered illustration of a Velux light pipe used in a bathroom with no side lighting. (Courtesy of:

Velux)


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Figure 24 Lightpipe in Morgan Lewis Office, Washington D.C that brings daylight in 12 stories. (Courtesy of:

https://www.flickr.com/photos/colt-tollfab-victoria/)


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Figure 25 Philosophy of color (Courtesy of: http://theultralinx.com/2012/02/psychology-colour-infographic/)


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Interviewer: Hello, my name is Ioana Fartadi-Scurtu and this interview is carried as part of my

dissertation research for the Bachelor of Architectural Technology and Construction Management. I

would like to point out that your answers will be anonymous and I will just use your profession title

for research purposes.

Question 1: We know that daylight in architecture has strong implications both in terms of visual

comfort and energy efficiency. In your opinion, which one is the most important and why?

A: This is a very good question. If you'd ask me two years ago, I'd say that energy efficiency is such an

critical factor to consider when it comes to daylight however today I think visual comfort is most

important. I find that light, both natural and artificial are treated as an added design feature in

architecture once a building form has been decided. I think we should step back and design with light

in mind from the beginning. It shouldn't be an added bonus but rather a pragmatic decision to always

design by.

B: I don’t think that you can say that one is more important than the other, it depends on the

projects. You know, which one you would choose to put more importance to. And of course, there

will also always be legal regulations that kind of provide the answer for this. So, I don’t think that you

can say that one is more important than the other, that really depends on what you’re trying to do.

C: I think it’s an interesting question because it´s difficult to say which one is the most important

because daylight is a complex thing in architecture. You could say that without any light there would

be no architecture, so in that sense that would be the most important thing, but I think also that if

you say, on the long term then energy efficiency is very important because, well, basically today we

are facing some big challenges where architecture plays a big role in talking about sustainability. So I

don´t know if I can actually answer that question in that way, I would just say that daylight is complex

in the architectural practice.

Question 2: Do you consider that buildings with a good daylighting strategy are of great

importance in Denmark especially during the winter time or the daylighting issue can be

overlooked in favor of other design features?

A: I think most certainly that daylight has and is becoming of more and more importance in Denmark.

You can see today that both detail in construction but also in architectural design is drawing

attention to well lit spaces that provide sufficient light to the habitants using the space. During

winter time, where we have a significant lack of daylight, we see that light therapy is becoming more

popular. Especially the encouragement of using light fixtures that are strongest in blue to keep a

higher brain activity rate.


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B: It’s always, traditionally, been very important in Denmark for around a century. I guess we’ve kind

of set -- our architects and design are very focused on lighting. And yes, it probably has to do with the

lack of light in certain times of the year. But that’s set, it doesn’t mean that it can’t in some cases be

overlooked. But at the same time, we also have some regulations again about what we can and

cannot do. But in general I think that most Danish architects would say that they always do consider

daylight an important factor.

C: Well, in Denmark we don’t have that much light so that´s why we are working quite a lot with

daylight. But again, I think that it quite depends on the project if you can kind of overlook other

things or other design features and I think it is very much about which project you are looking into. I

think that´s overall for any architectural project that there is a hierarchy of what is the most

important, but the daylight issue is something very well integrated into projects also, sometimes

when you don´t realize it, but it´s something that is within the building culture and it´s very close

related to the architectural program. Again, it’s difficult to say if daylight should actually be

overruled, depends on the project and the concept.

Question 3: Considering the amount of daylight hours available during the winter time in Denmark

are the physical and psychological benefits of daylight taken into account when designing a new

concept?

A: Yes, definitely. As an aspiring lighting designer we are taught to always be critical and think about

the end user. It is important that research continues to be done into circadian rhythms because there

are vital information in how to design with light.

B: Always, yes. Again, depending on what kind of project you’re doing. It will always be taken into

consideration and in pretty much every project there will also be some legal regulations that you

have to apply to.

C: I would probably say in most projects that they are not, but I would also say yes again, because

there is a lot of research concerning the benefits of getting daylight indoors and in some projects it is

used. You can see that in hospitals where they are actually open very much to get the daylight in. You

also see it in office spaces, where we have to have at least 2 or 3 % of daylight factor but it´s not only

because of the physical and psychological benefits, it’s also for saving energy and other things.

There’s a lot of research that we could look much more into.


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Question 4. Do you think that daylighting should be a primary focus from the early stages of

design? If yes, why? Keywords are sufficient.

A: I think both daylight and artificial light should be primary focuses in the early stages of design.

They should act as the dynamic-duo by crossing trans-disciplinary fields and applying them as good as

possible.

B: All factors should be a primary focus from the early design and as a BIM manager, of course, I’m

kind of trying to push different tools and among them are also daylighting simulation tools. That

should, of course, be a very important factor from the beginning, since it’s really annoying if you later

on – you find out that, for some reason, you’re not complying to the regulations or whatever, or

wishes of the client, and you, at the latest stage, have to redesign your building. So, of course, you

need to take this into account as early as possible. And, again, that’s I guess where I come in as a BIM

manager. I’m trying to push these early simulations as early as possible.

C: Yes, definitely, I think it should be a primary focus of the early stages, just like all the other aspects,

because the early stages of design is where the most critical design decisions are being made. With

daylighting for example, orientation and the early massings are very critical about how daylight is

going to be in the building and that is very difficult to change in the late project stages.

Question 5: Considering your previous experience with small and large scale projects in Denmark

and abroad, is daylight taken into account regularly from the early stages of design or is it

something that comes into question later, after the conceptual part?

A: Daylight is taken into account as early as possible. Some projects might vary depending on

function. For example, a hospital project will insist in the latest daylight solutions for benefiting the

patience while an office project will accept a beautiful skylight as a feature.

B: I would say it always is taken into account. The whole concept of early simulation is pretty new, so

maybe they are not used the way I would like them to be used, but I think it’s always taken into

account. Maybe just as a concept inside the mindset of the architect we’re doing it with. Again, I

think it’s one of those things that Danish architects in particular find themselves being good at.

C: Again yes and no. I think there is a lot of tacit knowledge we know when building and massing with

office spaces of that so many square meters, we have a room depth of so much and also room

height. We also know that phasing the South will probably get more direct sunlight in, which can give

some glare. So, I think that there is some tacit knowledge that´s built in every architect that works in

a project. But, when we come to projects that are more complex, then it´s actually going to be critical


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or if the program is complex. But also if we work abroad like on the other side of the world where we

don’t have that tacit knowledge then we actually get difficulties of using that experience that we

have and also maybe trying something totally different that we haven’t built before.

Question 6: Generally, based on your previous experience, are architects willing to do volumetric

changes, as well as changes in materials, openings and plot orientation in favor of achieving a good

daylighting strategy or is the daylighting strategy generally overlooked in favor of design integrity?

A: This is very different from project to project and depending on which phase you look at the work

environment, it is often the client that will be pointing the finger and the architect following orders.

However speaking from experience, there are professionals in the field that are always willing to do

the best of their abilities.

B: No, I think, again, this would be one of those things that, especially Danish architects would

consider very important and would always be willing to go through a great deal of work to get this

right.

C: Again, I think it depends really on how far the project is. Like, the later the project is in the stage,

the more difficult it is, especially with the massing but a lot of times in the late projects it's actually

when you are starting to choose the materials to help the daylight.

Question 7: In connection with the previous question - do you consider that design integrity is a

major impediment in achieving a good daylighting strategy? Why?

A: No I do not. In fact, there are many solutions to doing good daylight. It is just a matter of being

able to apply it into different buildings and their different purposes.

B: It’s like two sides of the same thing I guess.

C: I already answered it in the previous answers.

Question 8: What are the primary features of the architectural concept that face changes in favor

of a good daylighting strategy?

A: Location of the windows which are interlinked with the rotational position of the building are very

much changes in favor of good daylight strategy. Furthermore, glass solutions to not overheat the

spaces are vital and always increasingly smarter and better.

B: Depending on where the focus is – especially Danish architects wouldn’t consider design integrity

as being an important factor that should overweight daylight.


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C: I think if I understand the question right, then I would say that it's less deep floor plans and also

the room height are kind of the main parameters.

Question 9: Do you consider that available daylight simulation software (such as Ecotect, Velux

Daylight Visualizer, Relux among many others) have certain limitations that would form an

impediment against achieving useful results for planning with daylight? If yes, could you briefly

explain why?

A: There are a number of daylight simulation software available yet Velux Daylight Visualizer is

known to be most accurate to date. This does not mean the other software are wrong however Velux

has a close relationship with clients and their business model has helped to develop a very trustee

simulation software. That being said, we have to remember that these are tools that help us better

understand the building but also visualize easier information to be shared with the client and other

consultants.

B: Well the ones that are mentioned here are mostly external simulation program so you would

usually have to remodel stuff. You don’t have this natural flow of information that I am as a BIM

manager I’m trying to work towards, but on the other hand if you look just at the BIM platforms, the

simulation tools are not so great in so many cases these standalone simulations are the easiest way

to get a certain simulation. It’s not perfect but it’s better than nothing.

C: Just to understand it right, you are questioning if the simulation tools have limitations?

<Interviewer: Yes>. Then, definitely. I cannot remember who said it, so I cannot quote him but

someone said that all models are wrong and I totally believe that. The thing is that some models are

more useful than others, but you can see that every simulation is an abstraction of the physical world

and you have to keep in mind when you work with them that there is only a very specific area that

you investigate, you're not investigating everything that's there in the physical world.

Question 10: Are BIM simulations a more reliable and useful alternative to existing daylight

simulation specialized software (Ecotect, Velux Daylight Visualizer, Relux, etc.)? If yes, could you

briefly explain why?

A: I'm not sure as I would need further data in order to make a claim for this question.

B: There will be when we start using them really, but until that kind of works out in practice also, the

others do fine. When you start rebuilding stuff – on one hand you do redundant work which is

unnecessary and on the other hand you also you run the risks that the remodeled version is not fully

compatible with the actual model that you do for documentation, so you run the risks that there’s a

difference there. BIM simulations would at some point be more reliable since it’s the same


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information that you use for documentation as for simulation, but for certain practical reasons we

sometimes have to do some work around that.

C: Well, you can say that a BIM model will have more information about the building. Then you can

say yes, the simulation will be more reliable, but in case of being useful I'm questioning that because

the BIM model will probably appear at the later stages and it would be more difficult to change the

architecture.

Question 11: In your opinion, what are the most frequent issues that we need to face in order to

implement a clever daylighting strategy in architectural spaces in Denmark?

A: If we begin by treating daylight as a tool instead of as an exotic feature in the building process, we

can maximize the use of daylight by location and opening of the windows. We can develop intelligent

skylights that react both to space but also to their surroundings. Currently for example, in

Copenhagen we see that the renovation processes are issue we need to tackle, as there is a need to

re-new clever design solutions particularly when talking about daylight.

B: I think the biggest problem right now that we often put too much daylight in the summer. The

greatest challenge in most of our projects right now is that we have too much glass. That might be a

Danish problem. I guess we also see it in other places but the biggest problem right now is actually

keeping the sun out of our projects and that is a kind of a consideration that we have to face and this

where the simulations will probably be the only way to solve that problem.

C: Well, maybe it's a boring answer but I think that we have to implement more knowledge and

awareness and actually the research is already there. I think that, well, companies should have a

specialized group that works towards ways of implementing knowledge into the architectural phase

and trying to set up some work between professions early on the design stages.

Question 12: Should daylighting strategies vary according to the building scope?

A: Yes most definitely. I am repeating myself here but it is important to treat each building

differently. That is why we have standards to meet which should be used as primary requirements to

achieve what the client wishes.

B: No.

C: Yes, definitely.


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Question 13: Are choice of plot orientation and openings enough to achieve a good daylight

strategy?

A: No, they are most certainly not enough but always a good way to start the design process when

speaking about daylight.

B: In some cases they might be and in other cases they wouldn’t.

C: No, definitely not but it’s where we normally start.

Question 14: Besides plot orientation and openings, what do you think are the key features we

need to implement in a good daylighting plan for residential occupancy in Denmark to gain visual

comfort and energy efficiency?

A: My answer to the previous question 11 stands linked to this one. I will add that it is important to

also make further studies as to the uses of the spaces which would show how to light a space.

Certainly being careful not to overexpose materials with light and using what is currently available,

smart lighting which goes hand in hand with energy efficiency.

B: Yes, again, we have the tendency to kind of open a little too much right now. So we have lots of

daylights, but when it comes to comfort and the overheating and so on, we have a lot to learn. Also,

the regulations sometimes can be, you know, not really working. Regulations are not always so

logical. Sometimes going away from the regulations could actually get better results for comfort and

so on. So I think we are kind of in the process of getting this right. Now we have some simulation

tools that can try to help us out early in the process. And I guess also the legislators are trying to

figure out how to make the rules a little less rigid, so that you can actually do some alternative

versions of this sometimes. So, I can’t say what exactly -- where we will land on this, but I’m pretty

sure that in 10 years we will be a lot smarter on this issue.

C: I think there's a lot of stuff happening on the technical side, with windows. I've heard that now

they are actually trying to test 6 layered glass and you can work with different types of films that

both get you great daylighting quality and have some really high energy performance.

Question 15: Are materials and colors important in a daylight strategy?

A: In my opinion, they are very important. Just starting from the basis of exposure and reflectance,

the use of materials need to studied before implemented into a project. This is why we have clear

material specifications in LEED qualifications and somewhat in DGNB.

B: Yes.


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C: Yes

Question 16: Finally, on a scale from 1 to 10, (1 being least important and 10 being very important)

how would you rate the importance of having a strong daylighting strategy in residential buildings

in Denmark?

A: Currently, at 7 but closer to 8.

B: That would be a 9.

C: I think it's a 10, I think it's very important because it's really the beauty here in the North in

architecture that we are working very effectively with daylighting, where you really see how the

season vary and you get such a close connection to the nature.


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Daylight planning in Denmark’s residential architecture

© Ioana Farţadi-Scurtu

October 2015

Bachelor of Architectural Technology and Construction Management

Lillebælt Academy of Professional Higher Education