Light and Privacy
A proposal towards a testing and education standard
CODY TORGERSRUD
KTH ROYAL INSTITUTE OF TECHNOLOGY
Light & Privacy
A proposal towards a testing and education standard
KTH Royal Institute of Technology
School of Architecture and Built Environment
Architectural Lighting Design Master Program
Degree Project / AF270X VT20-1 / May 2020
I would like to thank my tutor for taking me on despite the distance and state of the world. Hamid, your help has been immeasurable, a million times thank you. I also want to thank my professors, Rodrigo, Foteini, Ute, Isabel and Gerhard for your lessons, guidance and, of course, time. And none of this would be possible without the support of my amazing parents Lollo and Dave. There are not enough words to convey the gratitude that I have for all you have done for me.
Abstract:
Keywords:
The transformation of the architects’ vision to architectural form is a lengthy process. From initial sketch to day-to-day life, a design is transformed through the reality of occupation. No matter how much effort is put into a design its final effectiveness is determined by the end user. The access to ample daylight balanced with an adequate sense of visual privacy within ones own home is not often accounted for within the planning process.
With current legislation making access to daylight a right within many developed countries, guar-anteeing that access within the dense urban environment can mean putting resident’s privacy into question when planning to meet these daylight requirements. Failing to consider the privacy needs of all residents, especially immigrant groups, can lead to privacy driven modifications coun-terproductive to the overall goal of increasing access to daylight. Resident modifications can, in turn, lead to reductions of daylight levels within the home. There is a need for a system of analysis when it comes to the balance of access to daylight and adequate visual privacy, connecting the critical impacts of these factors on the human physiology and psychology.
This proposal puts forward a system to analyze the relationship between the effective light trans-mission and the perceived visual privacy provided by a given visual privacy solution. The study is based off the analysis of current research regarding the effect of daylight on the human body, the importance of privacy within the home, the impact of cultural background on perception of priva-cy, and the impact of changing urban density on how people live. The research proposes a system of measurement taking into consideration both the quantitative effective daylight transmittance and a systematic qualitative analysis of perceived visual privacy through participant survey. The data collected would eventually be combined in a way that could be easily communicated to architects, designers, manufacturers and most importantly the end user. This system would be used to ensure that residents are able to effectively balance the level of privacy they require while mitigating the loss of daylight within their homes helping to insure the most benefits for the resi-dent regardless of what home they find themselves in.
Table of Contents:
1 Introduction
2 Motivation
3
Background Research
3.1 Daylight
3.2 Visual Privacy
3.3 Cultural Differences
3.4 Housing Density
4 Limitations
5
Proposed Methodology
5.1 Daylight
5.1.1
Metrics
5.1.2
Process
5.2 Privacy
5.2.1
Metrics
5.2.2
Process
6
Proposed Usage Disucssion
7
Conclusion
1 Introduction
Human beings have a wide range of needs when considering their living spaces. While size, location and finish are important, there are two factors that play a critical role in the long-term physiological and psychological health that are often not considered linked as part of the planning process. The access to ample daylight balanced with an adequate sense of visual privacy within one’s home is not often accounted for within the planning process. This lack of balance can easily be seen in urban centers that have undergone significant trans-formation in the size, density and cultural make-up of their populations in the last seventy years. Architects building with a subconscious mono-cultural bias are not necessary going to consid-er the constraints that a more socially modest culture may face when inhabiting one of their structures. This myopic architectural view even effects cities bases in more conservative countries through architectural colonization (Al Kodmany, 1999). And while an architect’s inten-tions may be pure the understanding that one’s own cultural background will not necessarily translate to final usage is often overlooked. This gap can quickly lead to the failure of the design.
A common inflection point in this process is the window. Windows placed by the architect to facilitate healthy, and often mandatory daylight levels within a home may become an issue when the visual access provided by the window violates the level of privacy needed within the home to feel safe. While many residents will add drapery or blinds to feel more comfort-able, not much thought is given to the overall effectiveness of these solutions in maintaining healthy daylight levels within the home. This modification of the home will be unique to the resident and can range from a simple drape to a structural addition. These solutions may often be referred to as interior or exterior shading devices within the architectural community, but within the scope of this research the term visual privacy solution (VPS) is used. These visual privacy solutions will also vary greatly depend-ing on the background culture of the resident, potentially resulting in extreme cases of fully blocking windows to ensure visual privacy. This proposal puts forward the creation of a system which can measure and quantify the physical and psychological effects of a given visual privacy solution, to help create a more balanced approach for the general popula-tion. From simple drapes to the architectural Mashrabiya each solution provides its own level
How, as designers, do we go about creating spaces that attempt to deliver
the most amount of daylight while retaining the highest level of privacy for a
range of peoples?
Light and Privacy
How Testing
Human Perception Privacy Metrics
View In Clear Warped Obscured Shadow Not Visible View Out Clear Warped Obscure Shadow Not Visible
Light Metrics Transmittance
Light Before Treatment Measured Natural light
Chosen Artificial Light
Light % After Treatment Tested within a “standard” room
Who Urban Dwellers
Existing Citizens Economic Migrants
Refugees Political
Environmental
What Rating System Score Card
Consumer Awareness Manufacture Awareness Developer Awareness Where Northern Europe Urban Centers Street Level Above Street Level Adjacent Building Below Street Level
Why Densification Migration Economic Job Opportunities Education Social Arts Culture Events Refugees Political War Persecution Environmental Natural Disasters Climate Crisis Environmental Lower Impact Living
Smaller Footprint Green Building Techniques
Health Physical Light Privacy Mental Light Privacy When Current Future Development
of daylight transmittance and perceived visu-al privacy. Anvisu-alyzing the existing research to develop and classify the metrics behind these factors will allow us to create a system of grad-ing. A system, that applied on a broader scale, would be able to be used by homeowners, architects and manufacturers alike to deter-mine the best solutions for getting the required privacy with minimal reduction of daylight levels. Education is critical in this process. This study seeks to propose the groundwork for a larger examination of visual privacy solutions towards both a market and educational testing standard.
2 Motivation
Visual privacy is something that is that is deep-ly important to me. Living most of my life as a nonstandard size has made me critically aware
of the public gaze. The understanding of how important the home is for being able to be free from this gaze has heightened my sensitivity to those from other cultural backgrounds and genders that deviate from Northern European standards. Add to this the growing research around the importance of daylight to the main-tenance of the day night cycle to human health, and the considerations for this study where laid out. The groundwork can be seen in an early mind map created around the concept (Fig. 2.1.). Living in Sweden it is easy to see how this preference towards light is a cultural norm. Simply by looking at the architecture around Stockholm it is easy to see the premium that
is placed on capturing as much daylight inside as possible. in this context, daylight is seen as a luxury commodity. The observation of this balance between privacy and demand for solar gratification is what inspired this exploration. While a window may provide bountiful light, the access to said light comes at the cost of priva-cy. This is especially prescient when looking at the increasingly dense and diverse urban center of Stockholm. Seeing the flow of people, and the growth of other cultures within the city underlines the importance of understanding the balance between daylight and privacy. Looking at how people treat their windows in a scientific way, and providing an accessible solution, is the best way of giving everyone the ideal balance of daylight and visual privacy.
3 Background
This research is built out of two competing factors that both carry a lot of importance to us as human beings, the balance between access to daylight and access to visual privacy. Look-ing back to our earliest ancestors can provide context to our modern dilemma. The dilemma of choosing between the exposed view of the surrounding world or the privacy of the shelter-ing cave is one that has been dealt with since prehistory (Hwang & Lee, 2018). While the march of development has shifted the balance away from access to daylight, the importance of daylight on the health of the human mind and body has never been more clear.
3.1 Daylight
Daylight as a term can be commonly misused. This is because it is not a singular thing. Day-light is the combined effect of three unique types of light. Direct sunlight is the light that passes through the atmosphere and falls onto the Earth’s surface in a single path. Reflected sunlight is the light that lands on the Earth’s surface and reflects back up towards our eyes. Skylight is the light diffused and reflected off the inner surface of the atmosphere creating what we perceive as the sky. These three types combined make up what we refer to as “day-light” (Fig. 3.1.1).
The importance of daylight is something that continues to emerge as research moves for-ward. Its health benefits, and importance to our natural systems, make sense at a basic level. We are creatures that evolved under the open sky. Humans were evolved for existing outside during daylight hours (Hwang & Lee, 2018). This evolution runs headlong into the modern lifestyle of the average person in the devel-oped world. More frequently than ever, jobs are worked inside, away from the reach of natural
light. These office-based jobs generally involve sitting in front of a computer screen for a major-ity of the day. Combine this with the growing de-pendence on technology in the rest of our lives and it means that we are spending a larger part of the day indoors, in front of screens. The com-bined effect of this reduces exposure to bright light during the day, while flooding the eye with high levels of light at night. A complete inversion of the patterns laid out in the natural world. The discovery of the non-visual ipRGC cells within the human eye means that beyond visual stimuli our bodies are responding to the light around us on a physiological level as well (Hannibal et al. 2004). This sensitivity to light has been tied to issues that affect the core of our sleep and wake cycles, our circadian clock. The exposure to higher levels of light at night and lower during the day shifts the working of the master circadian clock. This shift can neg-atively effect the production and secretion of hormones like melatonin and cortisol within the body (Tähkämö et al. 2018). In drastic cases like shift work, changes in melatonin secretion has been linked to higher risks for specific types cancer (Touitou et al. 2017).
ural circadian rhythm. Research suggest that access to full spectrum light with saturation in the green and blue wavelengths during the day is important to ensuring that the circadian clock is operating correctly. This light, rich in the blue and green wavelengths, aligns with the peak sensitivities of the ipRGC cells meaning a more effective light for stimulating the cells. Day-light in turn is going to be the best source for a broad-spectrum light of this nature due to its near full spectrum wavelengths (Veitch, 2012).
3.2 Visual Privacy
Privacy can be described as “the selective control of access to the self or to one’s group (Altman, 1975).” It comes down to a process of gatekeeping. In essence controlling the level of access the surrounding world has to you or your group. The process of privacy is one
that can be expressed either socially, through behavior, or physically, through location and distance. It, in itself, is a balancing act between uncomfortable exposure and alienation (Ped-erson, 1997). Because of this the home is central to the concept of personal privacy. In the modern context the home is considered the most private of places. The space where one can escape from the rest of the world and only interact with whomever they choose to.
Looking at Pederson’s (1997) work we can see his breakdown of the functions of privacy. For his research six factors were put together that all function as part of privacy in a larger sense. Of these factors; solitude, reserve, isolation, in-timacy with family, anonymity, and inin-timacy with friends, there is one that is especially pertinent when looking at the importance privacy within the home. “Solitude refers to placing yourself in a situation where other people cannot see or
hear what you are doing, e.g., going to one’s bedroom and closing the door. This permits a person to be undisturbed (Pederson, 1997).” This is an act of privacy that functions within a family, removing oneself to a place apart from the household and again from the world at large.
This ability to find refuge within one’s home serves a number of purposes. Solitude is found as a key component in contemplation, autonomy, and rejuvenation (Pederson, 1997). These are all important functions in keeping a healthy and balanced mind. With the influence of solitude being a controlling factor, it stands to reason that the feeling of privacy within the home would be critical in these functions.
While a lack of privacy can come from a number of places, what we are focusing on is visual privacy, or the ability to feel unob-served by others. This sense of visual pri-vacy is integral to solitude and being able to unlock the processes that it affords. The effects of privacy can be seen as profound. An understanding of how the lack of privacy can affect a person’s ability to process and grow is critical.
George Orwell understood this well. In writing 1984 the author sets out a dystopian Figure 3.2.1 - Plan and section view of philosopher Jeremy
world based around a state of observation. Cit-izens are constantly monitored, day in and day out, through video feeds located in their televi-sions. The only reason that the protagonist is able to start breaking through the oppressive shell of constant surveillance is the fact that he feels safe in his alcove, where the gaze of the government, staring straight into his room, cannot see (Liu, 2011).
Lack of visual privacy is seen as punishment, as a way to control and manipulate people. This is demonstrated through the planning and design of the Panopticon, a historical turning point in the development of the modern prison system ( Fig. 3.2.1 ). The consideration of privacy within the home is one that should never be ignored or overlooked. While what counts as private varies from person to person, the understand-ing of the value of privacy at the personal level is essential.
3.3 Cultural Differences
Visual privacy comes down to perception on a personal level. With that being said, there are some ranges that seem to be tied to larger pop-ulation factors like culture and religion. There is evidence to suggest that standards of privacy are heavily influenced by cultural background
(Garvey, 2005; Van Der Horst & Messing, 2006; Hessler, 1995).
In the evolving and changing demographics of our cities it is critical to understand our differ-ences in order to create cities that support all of their inhabitants. This can be especially true in capitals like Stockholm, where the cultural norms between native and immigrant commu-nities can be vast and cover extremely sensitive topics like religion, gender roles and the body. An example is the current tension around the rapid influx of Muslim populations within North-ern Europe.
The evolving makeup of a city means that groups of immigrants are often moved into existing housing stock. This change in perspec-tive between the cultural norms that a structure was originally designed for, and those of other backgrounds, can cause friction within the larg-er community. When a new group of citizens are perceived to fail in maintaining the cultural standards of transparency it can contribute to dissonance between that group and the domi-nant culture. This cultural dissonance can result in areas being abandon by the larger native culture or being relegated to a second- or third-class zones effectively creating cultural ghettos (Van Der Horst & Messing, 2006).
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Population Breakdown of Stockholm Metro Region
Foreign-born Born in Sweden
This effect can be seen in reverse of the Northern European model with more culturally conservative cities like Damascus. There is evi-dence that a more open and westernized archi-tectural style proved to be problematic to the sense of privacy of residence. This discomfort holds true even within the behavior and actions of the more liberal participants of surveys that chose to live in these more open and exposed buildings (Al-Kodmany, 1999).
These factors are pertinent in today’s changing cities. As the capitols of Northern Europe are influenced by waves of political, economic and environmental refugees the cultural makeup of these cities will continue to evolve and change from their historical norms (Fig. 3.3.1.). This pressure is going to mean that homes that may have been perfectly adequate for the needs of residents before suddenly become far to ex-posed for residents used to homes built around blocking the gaze of the outside world.
The adaptation process can lead to a buildup of privacy measures that end up cutting off access to daylight within the space. This
in-sulation of privacy can effectively deny new residents the important health benefit of day-light, potentially exacerbating a transition to the seasonal daylight changes of a more northerly latitude. The effect, putting them at a further disadvantage, and potentially hindering integra-tion into the fabric of the city at large.
3.4 Housing Density
Another factor effecting the light and privacy balance is that of housing density. Looking at the Stockholm Metro region there has been a population growth pushing into the city, noticeable over the last two decades. These changes show in the over 440% increase of housing units built within multi-unit blocks (Fig. 3.4.1.). Add onto this the loss of about 22 meters squared of usable space within these newly build units (Fig. 3.4.2.), and the and the 30% increase in population density of the region at large (Fig. 3.4.3.), and this is a pressure that cannot be ignored. This densification means that smaller units are being placed closer and closer to each other, increasing the chances for interactions that can violate a resident’s visual privacy. While housing density is not necessary
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Completed Residential Units
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Population Density per sq. Kilometer - Stockholm
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USEFUL FLOOR SPACE (NET) IN METERS SQ
Figure 3.4.1. - Graph detailing num-bers of units built in “multi-unit” build-ings (classified as those with three or more living units per building) in the Stockholm metro region. While this graph shows data starts in 1975 and covers multiple financial recessions within the larger Swedish and Global economy it is evident that there is a current building spike that has been growing since 2015. This aggressive growth is most likely a response to the pressure of housing demand that Stockholm has experienced over the last decade as well as growing trends in ownership of living units.
Figure 3.4.2. - Graph detailing, net, useful floor space in square meters of new apartment units built in multi-unit building in the Stockholm metro region. While there is some variance over the time measured, 1994 to 2018, there is a marked trend to-wards smaller spaces starting in the early 2000’s. While there has been a large increase in housing cost during this time that could be a pressure it can be theorized that a growing lack of space which could be impacting the overall sizes of the residential units being built. This is backed up by the spike in the number of units built over the same time within the area.
How can the balence of daylight vs privacy be best communicated? Research Process Defining Privacy Metrics Defining Daylight Metrics Defining Pressures on Cities Measurement
Technique Testing Method InteractionsViewer View Clairty
Subjective Testing Transmittance Ratio Testing Visual Privacy Solution Scorecard Education solution towards providing healthy balance between
daylight and visual privacy for a dense and
multi cultural cities.
Privacy Solution Details
Thesis Scope Proposed
a negative, it is a factor that must be considered when looking at the issues of balancing daylight and privacy.
4 Limitations
With this thesis there are some limitations in the scope of the project that need to be outlined. This proposal will only be looking at visual privacy during daylight hours and will not consider nighttime condition regarding access to view and visual privacy. In addition, this proposal will be looking at daylight effects only and will not consider the interior electric light as part of this process. Within the scope of this research the analysis of quality of view in the larger scale is not being analyzed in favor of establishing a methodology to analyze the balance between light transferred
and the impression of visual priva-cy. Due to the time constraints and current global pandemic the project will focus primary on Stockholm Sweden, this being the current location of study. The constraints of the COVID-19 Pandemic also mean that access to facilities has been cut limiting the range of testing to digital, small-scale models, and theoretical surveys.
5
Proposed Methodology
The structuring of the testing met-rics and process will be broken down into two streams. The daylight analysis and the privacy analysis will each provide their own structure and techniques that will feed into a score card format. This score card is intended to be part of a larger database that will allow for easy access to visual privacy solutions based on the type of interaction the end user is having with the outside world and what level of privacy they are looking for. The use of this would allow for a number of solutions to be presented side by side while also stressing effectiveness of daylight transmission to ensure that the end
balance of both for their home.
5.1 Daylight
The tools for measuring daylight are well es-tablished within the field. The daylight testing will be based around common practice and a complete approach to create the most stream-lined analysis that applies across a wide range of solutions.
5.1.1 Metrics
When looking at quantitative portion of the study there are a number of metrics that can be used. For this study we are going to be measure illuminance levels (Lux.) This has been chosen
A. B. C. Measurement Section Lorem ipsum Standard Wall Legend: Interior Measuring Zone Standard Window Exterior Measuring Zone 1 m .25 m .25 m .25 m .25 m 1 m .25 m .25 m .25 m .25 m 1 m .25 m .25 m .25 m .25 m Elevation Section A 1 m 1 m 1 m .5 m A A NOTE Measurement Point Legend: Standard Wall Standard Window NOTE:
This dimensions is not set. Measurement device is to be placed onto out-side and inout-side surface of visual privacy solution (VPS) that is being tested. As VPS will vary in depth the distance be-tween measurement points will a to match. Figure 5.1.1.1. - Schematic section of testing space. The widows, A, B and C, are called out as well as showing the exterior and interi-or measuring surfaces.
as it will provide results that can be directly compared to the standards required for many interior spaces. This will be tested through a simple process (Fig. 5.1.1.1.) measuring the light lux level outsize the widow/solution as well as inside the window/solution and ratio of loss. This simplification will mean that the percentag-es developed are not tied to a specific amount of light within the testing parameters and allows for a broader result, that can be better under-stood by a broad audience. In addition, this process allows for a much more situationally accurate result meaning that the test does not need to control for situations like weather conditions or precisely calibrating and testing luminous flux of the lighting array each time a new visual privacy solution needs to be tested.
5.1.2 Process
The process for testing utilizes the same mock space as the objective tests. The given solu-tion is placed on all three testing windows (A, B & C Fig. 5.1.1.1.). These locations will broad-en the range of testing allowing for a more comprehensive average (Figure 5.1.1.2.). The tests will be run with artificial light to allow for a more consistent process. The lighting will be designed to imitate natural skylight by being a full color spectrum source as well as being diffused. The lighting within the testing space should be of a level to supply at minimum 5000 lux at the outer surface of each of the testing windows with no privacy solution present.
5.2 Privacy
The analysis of perceived visual privacy calls for a much more complex structure of metrics and process. The metrics based around ob-served interactions and viewed through the lens of visual acuity.
5.2.1 Metrics
There has been little research around the creation and testing of metrics for determin-ing visual privacy. The testdetermin-ing that has been performed was not necessarily in depth and was designed to draw further attention to the
subject. Alkhalili, and team, focused around the importance of visual angle when judging perception (2018). The connection between distance, size and feeling of privacy is logical and acted as an important component with-in buildwith-ing out the testwith-ing metrics. While this testing is not analyzing just the single viewers perception of various spaces, but instead the sense of visual privacy of both the inside viewer and the outside viewer. This juxtaposition will show the difference in view clarity of a given solution and its effectiveness of creating visual privacy from outside in.
In addition to the distance of each viewer from the privacy solution the angle will play an important role in the perception of the viewer. In the observation of the urban setting of Stock-holm four main interactions between the inside viewer and the outside viewer were found.
Viewer interactions; when at least two
individ-uals are aware of the presence of each other through the format of a window. The four viewer interactions are defined as:
Ground Level - Figure 5.2.1.1. Above/Below - Figure 5.2.1.2. Below/Above - Figure 5.2.1.3. Across - Figure 5.2.1.4.
An interaction does not define a violation of visual privacy, but simply sets the characters in place to judge the reaction.
View Clarity; the perception of the structure of a
view. In the testing the viewer will be observing an object through the privacy solutions. A se-ries of five basic typologies has been created to help break down and communicate perception of view clarity. The view clarities are defined as the following: Clear - Figure 5.2.1.5. Warped - Figure 5.2.1.6. Obscured - Figure 5.2.1.7. Shadow - Figure 5.2.1.8. None - Figure 5.2.1.9.
Figure 5.2.1.1 -The first interaction is the most basic, the Across Interaction. This interaction details a window at street or ground level and be referred to as the ground level interaction. The interac-tion here is an eye to eye or similar height. The outside viewer is granted fairly free visual access to the space and whatever or whomever is inside. This issue is problematic in the urban setting as there is generally not a buffer between pedestrian traffic and the home. The lack of buffer means that a window at ground level is commonly looking out onto a public thoroughfare like a sidewalk. These are spaces that similarly positioned homes in suburban and rural areas but do not have the buffer of yards or fences to separate them from the larger general population.
Figure 5.2.1.3. - The inverse of the Above/Below, the Be-low/Above Interaction allows a similar amount of exposure as the previous viewer inter-action. As the focus of the exterior viewer is on seeing the floor, generally, the view in can feel more invasive. This is common in buildings where there is a garden level or basement floor that is not fully below grade. This view does little to protect the privacy of the person inside as the outside viewer is given broad visual access that is only really limited by the size of the window.
Figure 5.2.1.5. - The Clear View clarity style refers to a privacy solution with little to no effect. This means that the object on the other side of the window is distinctly per-ceivable, with notable details. This is a view clarity that would provide little no visual privacy. Schematic (Left) Model Example (Right).
Figure 5.2.1.6. - The Warped View visual clarity style refers to a privacy solution that obfuscates the view. This means that the general shape at large can be perceived but de-tails may be difficult to comprehend or process. This view clarity pro-vides low to medium visual privacy. Schematic (Left) Model Example (Right).
5.2.2 Process
The testing process for the visual privacy solutions will involve the surveying of volunteer participants. The creation of a virtual reality (VR) space captured within the full-scale test-ing space gives the experiment the potential for the widest reach of participants. The method would not be a digital rendering but, instead, a VR image. This process would allow the partic-ipant to feel as if they were in the testing space itself without requiring each participant to visit the testing site. Image sets could be created in an order that made sense for the resources of the research team. The surveys could be run off site at multiple locations with a little as a proctor and a VR headset or even remotely with online participants and proctors using smartphone integration.
Participant Selection:
A broad range of participants is vital to cre-ating a resource that communicates to as many segments of the population as possible. Information like gender, religion and cultural background will be recorded as part of the anonymous survey, and will be a searchable preference within the larger database. This design allows the end users to see solutions that are tailored to their background and world view. A base layer of background data that will be used to interpret the individual questionnaire results will be administered once a participant signs up. This will be collected through the Participant Pre-Survey Form (Appendix A) that will cover basic information about the survey participants basic details and background. Testing Layout:
A test will consist of an inside viewer perspec-tive and outside viewer perspecperspec-tive for each of
Figure 5.2.1.8. - The Shadow View visual clarity style refers to a privacy solution that diffuses the details of view. Depending on the level this can range from a blurring effect to simply a loose shadow on the other side. This view clarity can provide medium to high visual privacy. Schematic (Left) Model Example (Right).
the four visual interactions per visual solution. Therefore, for each given visual privacy solution there will be eight testing positions that need to be surveyed by each participant. The standards are held constant throughout the tests (Fig. 5.2.2.3.). All viewer perspectives will be tested from a height 1.5 meters above floor level. The inside perspectives are measured at 1 meter away from the inside of the window/visual pri-vacy solution (Fig. 5.2.2.4.). This puts the viewer within a reasonable distance of the window to be conducting day to day activities. The out-side perspectives are measured at 1.5 meters away from the outside surface of the window/ visual privacy solution. This, again would place the outside viewer within a realistic distance considering a sidewalk. Overall dimensions of the testing space can be found in Appendix B as well as photos of the space in scale model in Figure 5.2.2.1 and Figure 5.2.2.2.
Ground Level -The position at ground level is one of the most intimate of the four visual interactions, placing both perspectives at eye level and relatively close to one another. This interaction is seen on Figure 5.2.2.3 between position 1 (interior) and position 4 (exterior.) Above/Below -This interaction is common within the floors closest to ground level in a multi-story building and takes place between Floor 0, ground level, and Floor 1. The interac-tion takes place between Posiinterac-tion 2 (interior)
and Position 4 (exterior) and can be seen on Figure 5.2.2.3.
Below/Above-The Below/Above interaction is one that places the interior view at a lower po-sition than the exterior, spanning between the Floor -1, garden level, and Floor 0, ground level. The positions on Figure 5.2.2.3 are Position 3 (interior) and Position 5 (exterior.)
Across -This interaction is the one deviation from the standard dimensions as the “exteri-or” view is taken from another interior space meaning that it is also only spaced 1 meter from the inside of the window of its given space. This window itself being placed at the same height as the testing window but separated by 15 me-ters. This dimension was determined through the analysis of street widths around the Katari-na/Skanstull Neighborhoods of the Södermalm district in Stockholm (Figure 5.2.2.4.) The inter-action takes place between Position 2 (interior) and Position 6 (exterior) as per Figure 5.2.2.3. Visual Testing Questionnaire:
It is critical that the questionnaire for each test is kept quick due to the number of tests each solution requires. An example of the question-naire can be seen in Appendix A. It covers per-ception of privacy and ranking of the solution based from the participants perspective. This questionnaire will be filled out as the participant views the given solution.
A. B. C. 1. 2. 3. 4. 5. 6. 1.5 m Section C Measurement Point Legend: Standard Wall Standard Window VR View Angle
Figure 5.2.2.2. - Photos of scale model construction of testing structures detailed in Figures 5.1.1.1., 5.2.2.2., and 5.2.2.3.
Floor -1 Floor 0 Floor 1 C C C C C C Measurement Point Legend: Standard Wall Standard Window VR View Angle C. A. B. 3. 5. 1. 4. 2. 4. 6. 3 m 1 m 1.5 m 1.5 m 1 m 3 m 1.5 m 1 m 3 m 1 m 3 m
Åsogatan
->18.1 m<- Kocksgatan ->10.7 m<- Södermannagatan ->9.3 m<- Nytorgsgatan->17.9
m<-Bondegatan ->13.5 m<-Bjurholmsgatan ->12.0 m<-Östgötagatan ->11.3 m<-Skånegatan ->18.1 m<-Blekingegatan ->18.0 m<- Gotlandsgatan->20.1
6
Proposed Usage Discussion
The system as laid out would take the gath-ered data and format them into a standardized scorecard (Fig. 6.3 and 6.4.). This scorecard would be the basis for a larger data base col-lating the physical performance and the user perception of each visual privacy solution. This resource would be available to be shared by designers, architects and manufacturers to assist them in the design of new projects and products. More importantly it would provide an educational tool for the general public. The da-tabase would not only provide the most generic global results but would also allow the end user to drill down and rank the data on factors most important to them.
These scorecards are designed to quickly and simply communicate the basic results of the tests and surveys, including the style of visual interruption, daylight transmittance, and the visual privacy effectiveness. These results are featured prominently on the first page, and each have their own graphic associated. The visual interruption result is taken directly off the VPS Survey form and is identified with the view clarity schematic (Fig. 5.2.1.5 - 5.2.1.9.). The daylight effectiveness is the one result that is populated from the quantitative Lux measure-ments taken in the testing space. It features a unique graphic to help communicate the effec-tive transmittance percentage score (Fig. 6.1.). The visual privacy effectiveness is calculated from question two of the VPS Survey Form, and ranks the perception of visual privacy versus visual exposure. This result also features a unique graphic (Fig. 6.2.). The graphics for the daylight effectiveness, and privacy effective-ness are designed around the simple gauge style graphics common to many of the energy efficiency labels used for new appliances. This is done to help ease the civilian user into the results making it easier to understand results from a complex process.
More specialized results are found on the reverse page of the scorecard. This features special considerations, application ranking, and usage recommendations. Special con-siderations take in all the demographic data collected in the Participant Pre-Survey Forms
and processes them through the overall option question (question 4) of the PVS Survey Form. Application ranking is based off overall score, question four, and ranks the four viewer interac-tions for each visual privacy solution. This result indicates what concerns the VPS addresses best. The usage recommendations results are calculated between question eleven of the Participant Pre-Survey Form (visual privacy within the home) and question three of the PVS Survey Form (spaces within the home). This re-sult is designed to help rank usage between the various types of rooms within a home, making it easier to determine if a solution will be effective for the user’s space.
Figure 6.1. - Example of proposed “meter” graphic. This would be used to easily and quickly communicate the percentage of effec-tive light transmittance. The final percentage would be listed as a calculated percentage, as opposed to the ranges shown here. The look of these graphics is designed to resemble the energy efficiency graphics required for new electrical appliances throughout Europe and the United States. This is done purposely to create a sense of existing knowledge with the user making the overall process of using the database a much less intimidating prospect. In addition to this the colors are chosen to help reinforce the light to dark percentages.
Figure 6.2. - Example of proposed graphic representation for the overall privacy score to be used on the scorecard. If reached in a general way the information will represent a global score, if filtered through the setting of cultural background, age, etc., it will adjust to the score as filtered through the factors selected.
0-20%
Effective Transmittance21-40%
Effective Transmittance41-60%
Effective Transmittance61-80%
Effective Transmittance92%
Effective Transmittance Semi-Private Semi-Exposed Exposed Private VeryExposedVery Exposed ExposedSemi- PrivateSemi- Private PrivateVery
Exposed PrivateVery
Semi-Private Semi-Exposed Exposed Private Very
Exposed PrivateVery
Semi-Private Semi-Exposed Exposed Private Very
Exposed PrivateVery
Semi-Private Semi-Exposed Exposed Private Very
Exposed PrivateVery
Semi-Private Semi-Exposed Exposed Private Very
Exposed PrivateVery
Semi-Private Semi-Exposed Exposed Private Very
Visual Privacy Survey Score Card
Name: Typology: Installation Type : Materials : Manufacture:000000
Style of Visual Interruption :
Daylight Effectiveness :
Perceived Visual Privacy Survey Form: Question 1: Type of Privcacy
Visual Privacy Effectiveness :
Perceived Visual Privacy Survey Form:
Question 2: Overall Impression of Visual Privacy Quantitative Testing Results
Visual Clarity Schematic Effective Transmittance Graphic Visual Privacy Graphic Image of Visual Privacy Solution
Visual Privacy Survey Score Card
000000
Application Ranking : Speical Considerations :
Participant Pre-Survey Form: Question 1 : Age
Question 2 : Height
Question 3 : Gender Identity Question 4 : Education Level Question 5 : Nationality
Question 6 : Number of Years Lived In Sweden Question 7 : Home Status +
Question 8 : Household Makeup + Question 9 : Household Size Processed through
Perceived Visual Privacy Survey Form: Question 4: Overall Opinion
Viewer Interaction
Top Ranked Viewer Interaction Second Ranked
Usage Recommendations :
Participant Pre-Survey Form: Question 11: Type of Privcacy
Processed Through
Perceived Visual Privacy Survey Forms: Question 3: Spaces Within the Home
Light & Privacy
Presentation
Government
Agencies Participation Industry KnowledgePublic
Funding + Research Assistance
Funding +
Participation Awareness Social
Research Start Build Testing Facility Began Testing + Start Image Database Initiate Suvery Program Process Results + Build Website / Release Results Through Site
Figure 7.1. - The proposed structure of the research moving forward is designed to be able to improve general knowledge about daylight and its interaction with our homes. In addition to this it would provide valuable data back to the industrial players and government agencies that are willing to provide funding. This created a viable research structure that can be grown and expanded upon.
potential of driving new sales and provides a viable incentive for funding. The funding would also allow access to valuable raw market data that would be of great value to those seeking to take the temperature of the general public or predict trends.
There is also the potential for expansion of sur-veys with more detailed questions added while still utilizing the same image sets. This means that the project has the potential to scale or adjust depending on the environment it is being run in. This flexibility provides a growable platform meaning that the system can expand along with new technology and developing interest in many locations around the world
7 Conclusion
Humans deserve a living situation that provides them with both adequate daylight as well as a sense of privacy that meets their needs. While the balance between these factors is not yet deeply explored it deserves attention within the growing conversation around the importance of daylight to our minds and bodies.
As the world changes around us the way we live will need to change. Understanding how people interact, control and perceive the balance of daylight and visual privacy will help prepare us to react to a changing world and influence how we live in it.
With more research we open doors that can help improve the quality life for many. The need to understand the interactions between the impact of light on human physiology, the per-ception of visual privacy on human psychology, and the evolving urban landscapes that make up our cities will require additional research. This paper proposes a method through which the importance of this balance can be effective-ly communicated.
8
Appendixes - A
Participant Pre-Survey Form
Tester ID:Date: Site ID:
Form: 0A
Please note your Tester ID, you will need to confirm this on each individual test form.Please answer all questions as fully as possible. All information is kept anonymous and is purely for research pur-poses. If you have any concerns or need clarity on any of the questions please ask your testing supervisor.
Question 5 : Nationality
Question 3 : Gender Identity Question 1 : Age
Question 4 : Education Level
Please list as many as apply:
Female Male Non-Binary
Genderfluid Other - Please List _________________ Primary Education Secondary Education Trade/Vocational School Masters Program Doctorate
Other - Please List
__________________________
Question 2 : Height
cm years
-_______________________________
Question 6 : Number of Years Lived In Sweden
years -_______________________________
-_______________________________
Question 7 : Home Status
Rent – Private
Rent – Government Own – Single Family Own – Condominium
Please select one:
Please select highest level reached:
Question 8 : Household Makeup
Please select one:
Live Alone Live with Partner
Live with Partner & Children
Live with Parent/Parents Live with Extended Family Live with Roommates (Non Family) Live with Children
Question 9 : Household Size
Please amount of people within your household:
1 2 3 to 5
6 to 7 8+
Please continue to next page.
8
Appendixes - A
Participant Pre-Survey Form
Tester ID:Date: Site ID:
Form: 0B
Question 10: Perception of Visual PrivacyPlease note any keywords that come to mind with the following concepts:
Privacy : ________________________________________________________________________ ________________________________________________________________________ Visual Privacy : ________________________________________________________________________ ________________________________________________________________________
Question 11: Visual Privacy Within the Home
Please Rank the read the descriptions of levels of privacy and then rank the list of rooms to
A. Semi-Public Space B. Semi Private Space C. Private Space
Spaces that are regularly visited by guests outside the family.
Spaces that are sometimes visited by guests but generally reserved for household mem-bers.
Spaces reserved for only household members or for use by one person at a time.
A B C 1. Entry / Hall A B C 2. Living Room / Lounge A B C 3. Dining Room (Formal) A B C 4. Dining Area (Casual / Eat-In) A B C 5. Kitchen A B C 6. Family Room / Great Room A B C 7. Enclosed Porch / Sunroom A B C 8. Bathroom (Bath / Shower) A B C 9. WC / Lavitory (Toilet) A B C 10. Bedroom A B C 11. Closet / Dressing Room A B C 12. Laundry Room
8
Appendixes - A
Very Exposed
Test Number:
Perceived Visual Privacy Survey
Please confirm your Tester ID and Form Number before starting.
SURVEY INSTRUCTIONS:
You are being presented with a unique visual privacy solution added to a window. Outside of the window and solution is another person. Please take a look through this solution and at the person. The questions below will be regarding your impres-sion of visual privacy within the space in regards to that person.
Tester ID: Date:
Question 1: Type of Privacy
Question 2: Impression of Visual Privacy
Question 3: Spaces Within The Home
1. Semi-Public Space
2. Semi Private Space
3. Private Space Spaces that are regularly visited by guests outside the family.
Spaces that are sometimes vis-ited by guests but generally re-served for household members.
Spaces reserved for only household members or for use by one person at a time.
Clear: Any impressions/keywords: __________________________________ __________________________________ __________________________________ __________________________________ __________________________________ __________________________________ __________________________________
Below is a list of visual effects with their descriptions. Please select the effects that best matches your perception of the view through the visual privacy solution. Please note any impressions and/or keywords that come to mind.
On a scale of 1 to 5, one being feeling exposed and five being feeling isolated, please rank the overall effectiveness of the visual privacy solution in giving you a sense of privacy within the scenario.
On a scale on 1 to 5, one being ineffective and 5 being highly effective, please rank the effectiveness of this visual privacy solution for the following types of spaces within the home:
Object that is fully visible.
Warped: Object that can be seen as a whole but where details may not be clear.
Obscured: Object where some details can be seen and some details are blocked. Shadow:
Object that can be seen in shadow but where fine details cannot be deter-mined. None: Object cannot be observed. 1 2 3 4 5 Highly
Ineffective Ineffective Neural Effective EffectiveHighly
1 2 3 4 5
1 2 3 4 5
Form: 1A
Question 4: Overall Opinion
Is this a solution you would use in your own home? Please answer yes or no. Yes No
Your position is indicated by the dotted figured. 1 2 3 4 5 6 Exposed Semi-Exposed Semi-Private Private Very Private
8
Appendixes - B
Floor -1 Floor 0 Floor 1 C C C C C C Measurement Point Legend: Standard Wall Standard Window VR View Angle C. A. B. 3. 5. 1. 4. 2. 4. 6. 3 m 1 m 1 m 1 m 3 m 1 m 1 m 1 m 3 m 1 m 1 m 1 m 15 m 4 m 4 m 15 m 4 m 4 m 15 m 4 m 4 m8
Appendixes - B
A. B. C. 2.5 m 1 m 1 m .5 m 2.5 m 1.5 m 1 m Section C Standard Wall Legend: Standard Window8
Images Cited
Figure 0.1 – Photo, 2020. Cody Torgersrud. Figure 1.1 – Photocollage, 2020. Cody Torgersrud. Figure 2.1 – Mental map created using application Mind-Note, 2020. Cody Torgersrud.
Figure 3.1.1 – Schematic daylight breakdown, 2020. Cody Torgersrud
Figure 3.2.1 – Partial plan and section of Panopticon
de-sign. Bentham, J. (1843) ‘Plan of the Panopticon’, The
works of Jeremy Bentham, vol. IV, pp. 172-3. <https:// commons.wikimedia.org/wiki/File:Panopticon.jpg>
Figure 3.2.2 – Photocollage, 2020. Cody Torgersrud. Figure 3.3.1 - Graph population of both Swedish born and foreign-born citizens within the Stockholm metro region 2000-2019, 2020. Cody Torgersrud. Raw data source, Swedish Statistics Agency.
Figure 3.4.1. – Graph completed residential units in multi-unit buildings within the Stockholm metro region 1975-2019, 2020. Cody Torgersrud. Raw data source, Swedish Statistic Agency.
Figure 3.4.2. – Graph useful floor space in square meters of new apartment units built in multi-unit building in the Stockholm metro region 1994-2018, 2020. Cody Torg-ersrud. Raw data source, Swedish Statistic Agency. Figure 3.4.3. – Graph population density of the Stock-holm metro region 2000 and 2019, 2020. Cody Torg-ersrud
Figure 5.1. – Process Flow Chart, 2020. Cody Torg-ersrud. Made using Drawio.
Figure 5.1.1.1. - Schematic section of Lux testing space, 2020. Cody Torgersrud.
Figure 5.1.1.2. - Schematic elevation and section detailing the placement of illuminance measurement points for quantitative testing, 2020. Cody Torgersrud.
Figure 5.2.1.1. – Schematic of Visual Interaction – Ground, 2020. Cody Torgersrud.
Figure 5.2.1.2. - Schematic of Visual Interaction – Above/ Below, 2020. Cody Torgersrud.
Figure 5.2.1.3. - Schematic of Visual Interaction – Below/ Above, 2020. Cody Torgersrud.
Figure 5.2.1.4. - Schematic of Visual Interaction – Across, 2020. Cody Torgersrud.
Figure 5.2.1.5. – Schematic and Photo example of View Clarity – Clear, 2020. Cody Torgersrud.
Figure 5.2.1.6. - Schematic and Photo example of View Clarity – Warped, 2020. Cody Torgersrud.
Figure 5.2.1.7. - Schematic and Photo example of View Clarity – Warped, 2020. Cody Torgersrud.
Figure 5.2.1.8. - Schematic and Photo example of View Clarity – Shadow, 2020. Cody Torgersrud.
Figure 5.2.1.9. - Schematic and Photo example of View Clarity – None, 2020. Cody Torgersrud.
Figure 5.2.2.1. – Photos of scale model of testing space, 2020. Cody Torgersrud.
Figure 5.2.2.2. - Photos of scale model of testing space, 2020. Cody Torgersrud.
Figure 5.2.2.3. – Schematic section of testing space, 2020. Cody Torgersrud.
Figure 5.2.2.4. - Schematic floor plans of testing space, 2020. Cody Torgersrud.
Figure 5.2.2.5. – Graphic showing photos of streets with their width measurements all marked out on a local map of Soder-malm, 2020. Cody Torgersrud.
Figure 6.1. – Graphics generated for usage with proposed score card system, 2020. Cody Torgersrud.
Figure 6.2. - Graphics generated for usage with proposed score card system, 2020. Cody Torgersrud.
Figure 6.3. - Scorecard, proposed layout – page one, 2020. Cody Torgersrud. .
Figure 6.4. - Scorecard, proposed layout – page two, 2020. Cody Torgersrud.
Figure 7.1. - Flowchart showing next steps of research pro-cess, 2020. Cody Torgersrud. Made using Drawio.
Figure 8.1. – Survey form, proposed background survey, 2020. Cody Torgersrud.
Figure 8.2. – Survey form, proposed background survey, 2020. Cody Torgersrud.
Figure 8.3. - Survey form, proposed testing survey, 2020. Cody Torgersrud.
Figure 8.4. – Schematic floor plans of testing space detailing critical measurements, 2020. Cody Torgersrud.
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