Variable area lightshelf system

A variation of the static lightshelf system, the variable area lightshelf is designed to be a dynamic system whereby the Figure 6.11 Daylight penetration in a room with an oblique lightshelf. Figure 6.11 Daylight penetration in a room with an oblique lightshelf. position of the lightshelf moves to optimize sunlight penetration according to time of day or season. As shown in Figure 6.12 (a) and (b) a highly reflective film moves between two positions to optimize reflection inside the space. This...

Clerestory system

A clerestory is also a side window but one that is placed high in the wall. It is usually contained in a part of the building that rises clear of the roof. Generally, it doesn't provide views towards the exterior but permits a deeper penetration of daylight into the room than a standard side window (Figure 6.5) while giving little glare discomfort to the occupants of the room. Like a standard side window, a south-facing clerestory will produce higher daylight illumination than one that faces...

Energy Crisis

The oil embargo and the energy crisis of 1973 led to increased interest in energy conservation and the use of renewable energy sources such as solar power. Solar architecture was a direct response to the oil crisis, and its popularity grew in the late 1970s, particularly in the American southwest where there is abundant sunlight. Passive solar design principles were soon adapted to climates beyond that of the American southwest, as new technologies emerged and know-how improved. As concern grew...

Side window

Daylight Penetration

Side windows include view and non-view elements, that is, windows and clerestory, respectively. Traditional side windows tend to produce overly lit areas near the window and dimmer conditions elsewhere, especially if the room is deep. The light distribution differs depending on sky conditions. Overcast skies provide a deeper penetration of diffuse daylight than clear skies the shadows are, however, much softer and glare tends to be more severe because the sky is brighter (Robbins, 1986). In...

Light And The Human Endocrine System

Light affects our bodies in two ways. In the first, light impinges on the retina of our eyes and, through our vision system, affects our metabolism and our endocrine and hormone systems. In the second, it interacts with our skin by way of photosynthesis and produces vitamin D. Most of our body's life-sustaining functions are controlled by the hypothalamus, an area of the brain below the thalamus (Figure 3.1). The hypothalamus is responsible for a number of metabolic processes and for such...

The Industrial Revolution And The Modern

Gustave Dore Ville Industrial Revolution

During the mid-eighteenth century, the early years of the Industrial Revolution, Western Europe witnessed enormous economic and social changes as massive numbers of people migrated from rural areas to urban centers to seek work Figure 1.20 The Baths of Caracalla built in Rome between ad 212 and ad 216 (courtesy of Dreamstime). Figure 1.20 The Baths of Caracalla built in Rome between ad 212 and ad 216 (courtesy of Dreamstime). in the growing number of factories. Skyrocketing demands for housing...

Sidelighting Systems

Most sidelighting systems are designed to overcome the problem of uneven distribution of natural light resulting from the use of traditional side windows. Effective sidelighting systems operate by reducing excessive daylight levels near the windows and increasing them in areas away from the windows, thus giving rise to a more balanced daylight distribution throughout the room. Adding devices to the window glazing such as lightshelves, prisms or mirrored louvers offers a viable sidelighting...

Prismatic systems

Anidolic Daylight System

Prismatic glazing is designed to change the direction of incoming sunlight and redirect it by way of refraction and reflection. The basic operational principle of prismatic panels in sidelighting applications is depicted in Figures 6.14 and 6.15. As a ray of light hits the prism, its direction is altered because of refraction. A portion of it is then reflected upward towards the ceiling and onward towards the back of the room. Figure 6.12 The variable area lightshelf system with two positions,...

Dietary Supplements

The debate about whether sunlight is more effective than dietary supplements in the production of vitamin D has been examined in two studies, one in the United States and the other in Sweden. The American study (Webb et al., 1990) found that seasonal variations in serum 25(OH)D concentrations (vitamin D) caused by exposure to sunlight were highest in subjects with high mobility and declined substantially and proportionally as subjects became less mobile, irrespective of vitamin D dietary...

How Much Vitamin D Is Needed

According to several sources (Sardar et al., 1996 Glorieux and Feldman, 1997 Holick, 1999), the need for vitamin D photosynthesis can range from 15 minutes a day, three or four times a week, to three hours a day, three or four times a week. The length of exposure depends on the type of skin, the season, and the geographic location. Fifteen minutes of sunlight will produce enough Vitamin D to last for several days, even when the subject is wearing light clothing however, three or more hours are...

The Psychology Of Daylighting And Windows

Daylight is inextricably linked to windows and openings within the exterior envelope of a building. The two cannot be separated under typical design approaches, although it is technologically possible to bring in daylight without windows through the use of light pipes and other strategies. Figure 5.9 Sunlight brought into an underground office 30 meters below ground on the campus of the University of Minnesota (photograph M. Boubekri). Figure 5.9 Sunlight brought into an underground office 30...

Contents

1 Designing with the sun A historical perspective 9 1.2 Sunlight informing cave and underground architecture 12 1.3 Sun-informed architecture of classical 1.4 Sunlight in the architecture of 1.5 The Industrial Revolution and the 2 Daylighting legislation 41 2.1 Solar zoning legislation 42 2.2 Legislation based on window size 48 2.3 Quantity of illumination legislation 49 3 Seasonal Affective Disorder, depression, and their relationship to daylight 53 3.1 Light and the human endocrine system 53...

Toplighting Systems Skylight system

A skylight system is one of the simplest toplighting strategies. It usually provides a horizontal or slanted opening in the roof of a building and is designed to capture sunlight when the sun is high in the sky and diffuse light from the zenithal area of the sky vault, and introduce it into the portion of the room under the skylight. This daylighting approach can be used only for the top floor of a multi-story building or for single-story buildings. Several skylights uniformly distributed...

Cancer And The Role Of Sunlight And Vitamin D

Skin cancer has many causes but UV radiation is one. The harmful effects of UV radiation may be prevented by avoiding excessive exposure to sunlight and other sources of UV radiation. This type of cancer is the type increasing most quickly in the United States and is the most commonly diagnosed malignancy, exceeding lung, breast, colon, or prostate cancer. More than one million Americans will be diagnosed with skin cancer in 2007 (American Cancer Society, 2007). While skin cancer can be caused...

Light And The School Environment

Schools are another type of building that received the attention of ergonomists and where the contribution of day-lighting could be verifiably demonstrated. The architecture of school buildings can shape the way we teach and learn. In the five years between 2002 and 2007, more than 1000 schools were built each year in order to meet the demand of students in kindergarten and elementary schools in the United States alone. Architects and lighting ergonomists have taken a keen interest in the...

Roof monitor and sawtooth systems

Sun Tracker For Light Pipes

Roof monitors (Figure 6.20 ) and sawtooth systems (Figure 6.21) are toplighting strategies that differ primarily in their shapes. Under these systems, light is captured through vertical or sloped openings in the roof. These openings can be designed to capture sunlight at certain times of the day or of the year, depending on the requirements of the building. Roof monitors can be single-sided or two-sided. Single-sided Figure 6.23 A light pipe system with its various sunlight collection and light...

Designing with the sun A historical perspective

1.2 Sunlight informing cave and underground architecture 1.3 Sun-informed architecture of classical Greece 1.4 Sunlight in the architecture of classical Rome 1.5 The Industrial Revolution and the Modern Age As a formal subject of architectural study, daylighting arguably originated in northern Europe in the late nineteenth and early twentieth centuries. However, in one way or another, we have made use of the sun since the beginning of man's existence. It is said that the history of architecture...

Psychology of lighting

5.2 The psychology of daylighting and windows 5.3 Psychology of light and productivity 5.4 Light and the school environment 5.5 Daylight, windows and the therapeutic environment Because we are dependent on light for perception, it is natural that we should be psychologically affected by it. Throughout our history we have attached metaphysical, even divine, qualities to light. Light plays a central role in our everyday lives and consciousness through the physiological processes that connect our...

Health And Spectral Quality Of Light

The spectral composition of light refers to how much of each wavelength of the visible spectrum, which ranges from 380 nm to 770 nm, a particular light source emits. Figures 4.7 and 4.8 provide a comparison of the spectral compositions of a standard 'cool white' fluorescent light source and daylight. Spectral quality is a complex term that mainly refers to how warm or cool a light appears (correlated color temperature of light, CCT) and the shift of color (Color Rendering Index, CRI) that it...

Conclusion

When properly designed, daylighting can provide significant energy savings for building owners. With recent concerns over global warming and the need to conserve fossil fuels, it is imperative to use daylighting as a primary strategy for building illumination. Daylight, or the lack thereof, affects in no small way the psychological and physiological health of building occupants and their overall well-being. In addition, windows connect those who are confined indoors with the outdoors and allow...

Multiple Sclerosis And The Role Of Sunlight And Vitamin D

There are millions of people who are afflicted by multiple sclerosis (MS), one of several degenerative diseases that, like diabetes type 1 and rheumatoid arthritis, afflict millions of people. There are about 85 people with MS for every 10 000 people in the USA. It is estimated that the worldwide population with MS is around 2.5 million and that about 50 more females are afflicted with MS than males (Noonan, 2002 MS Society Statistics, 2006). Data show that MS is more prevalent in latitudinal...

Light And Mood

Initial studies exploring lighting and human behavior focused on our preferences in lighting conditions, particularly in the workplace. The common results among these studies suggest that people prefer much higher light levels Figure 5.4 Tadao's Chapel of Light in Osaka, Japan (courtesy of Tadao Ando Architects). Figure 5.4 Tadao's Chapel of Light in Osaka, Japan (courtesy of Tadao Ando Architects). than those typically recommended by professional organizations such as the Illuminating...

Daylight And Seasonal Affective Disorder

The seasonal depression often found among people living in northern latitudes and typically referred to as Seasonal Affective Disorder (SAD) is a commonly known effect of light that is related to our endocrinal system. The term was first used by Dr Norman E. Rosenthal in 1981 to describe the depression brought about by lack of daylight. SAD is an emotional disorder characterized by drastic mood swings, lowered energy, and depression. According to Avery and colleagues (2001), more than 10 of the...

Stress And Anxiety In Relation To Daylight

Cortisol, known also as the 'stress hormone,' is a cortico-steroid hormone produced by the adrenal cortex. It follows a diurnal pattern with high values during the day and low values at night (Hollwich, 1979 Scheer and Buijs, 1999). It also exhibits a seasonal variation, with more stress hormones produced in summer than in winter (Erikson and Kuller, 1983 Kuller and Lindsten, 1992). Abnormally high levels of cortisol increase blood pressure and blood sugar levels, may cause infertility in...

Sunlight In The Architecture Of Classical Rome

Architecture Greek House

Roman civilization is often grouped into 'classical antiquity' with ancient Greece, a civilization that inspired much of the culture of ancient Rome, and we should not be surprised to discover that, when it comes to solar design principles, the Romans applied them just as the Greeks had done. The writings of Vitruvius, the eminent Roman architect in the first century bc, influenced architects for centuries to come, including Palladio from the Rennaissance period and up to and including the...

Solar Zoning Legislation

It was practiced by the ancient Greeks and Romans during the classical periods as well as by other cultures at various times and in various places around the globe. In the United States, Native Americans valued solar access, as evidenced in the layered architecture of the pueblos of the American southwest. Formally speaking, however, and until the mid-nineteenth century, solar rights in the United States tended to be protected through the doctrine of Ancient...

Introduction

Without question, a causal relationship exists between the indoor environment and human health. The need for housing regulations and urban planning policies dates back to the mid-nineteenth century, when it became apparent that rampant diseases and epidemics in many cities of the newly industrialized world were caused partially by the physical ambient environment and were a problem to be dealt with. Deplorable sanitary conditions prevailed and were exacerbated by large migrations from villages...

References

Towards a new kind of office lighting study for a human interactive lighting system. Unpublished Master's thesis, Technical University of Eindhoven, The Netherlands. Acheson, E., Bachrach, C.A. and Wright, F.M. 1960 . Some comments on the relationship of the distribution of multiple sclerosis to latitude, solar radiation and other variables. Acta Pshychiatrica Scandinavica 35 suppl. 147 , 132-47. Alimoglu, M.K. and Donmez, L. 2005 . Daylight exposure and the other predictors of...

Anidolic zenithal collector system

Anidolic Zenithal Openings System

The zenithal anidolic system is comprised of two concentrating mirrors of parabolic shape that capture the incoming Figure 6.13 Light-redirecting louver system. Figure 6.13 Light-redirecting louver system. Figure 6.14 Prismatic panel inserted within a side window redirecting incoming sunlight. Figure 6.14 Prismatic panel inserted within a side window redirecting incoming sunlight. Figure 6.15 Refraction of an incoming sun ray within the prism provoking a change of direction and improving...