DAYLIGHT Symposium 2009
13 MAY 2009
Daylight – a Gift of Nature
by Nick Baker

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

It is perhaps a little surprising that these words were written by a scientist, R. G. Hopkinson, and not a poet. His book, published in the early 60’s, was a technical book, often regarded as the bible of daylighting science. In it, he presented the state-of-the-art on all technical aspects of daylight, mainly relating to its value as functional illumination. But he also alluded to the non-technical value of daylight. Ironically, it was published at a time when daylight was just ceasing to be an essential asset to the functioning of a building, brought about by a combination of cheap energy and increased luminous efficacy of lamps.

Both qualities are recognised today, particularly the technical value of daylight in avoiding the need for artificial lighting. However, it is probably fair to say, that both are still grossly undervalued. One only has to observe the prevalence of artificial light during daylit hours in buildings that their designers would strongly defend as being “daylit”, to see the truth of this claim. Furthermore, although there is documented evidence of the psychological and physiological value of daylight and views to the outside, these considerations often have a low priority in the building designer’s mind compared with more formal and aesthetic issues.

This paper reviews these two qualities separately, and then looks at them holistically, proposing that the whole may be greater than the sum of the parts. It goes on to suggest that this relates to our evolved response to daylight, as yet unchanged genetically, since the time mankind’s daily routine was still ruled by the rhythm of night and day. It is perhaps, the very source of this gift – nature, which makes it so valuable.

Nick Baker originally studied physics, but soon moved into architecture, working in education, research and consultancy. He has published on energy use in buildings, thermal comfort, and daylighting, and is the co-author of Daylighting Design of Buildings (James and James, London, 2002). He is currently a tutor and senior researcher associate at the Department of Architecture, University of Cambridge.

Circadian Photoreception: More than meets the eye
by Steven W. Lockley

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

In addition to visual function, the mammalian eye detects light for a range of behavioral and physiological responses separate and apart from sight. In humans, ocular light exposure resets the endogenous circadian pacemaker, suppresses synthesis of the pineal hormone melatonin, enhances morning cortisol production, increases heart rate and core body temperature, induces pupillary constriction, and improves subjective and objective measures of alertness.

Recently, major advances have been made in understanding how light is detected by the eye to transduce the circadian, neuroendocrine and neurobehavioral effects of light. A novel photoreceptor system has been discovered in the mammalian eye, including humans, that is anatomically and functionally distinct from the visual system. A novel photopigment, melanopsin, primarily mediates these responses to light via a small number of intrinsically short photosensitive retinal ganglion cells. These cells, and therefore our ‘non-visual’ responses to light, are most sensitive to shortwavelength blue light (max ~460-480 nm).

Short-wavelength light has the potential to be developed for a range of therapeutic uses including treatment of sleep problems induced by circadian rhythm disorders (shift-work, jetlag, advanced and delayed sleep phase syndrome, aging) or entrainment of the circadian system to unusual day-lengths (e.g., long-duration space flight, submariners, Antarctica). Preliminary studies have also shown that it can be used to treat Seasonal Affective Disorder and may be useful for correcting rest-activity disruption in dementia. The alerting effects of short-wavelength light also suggest that it can be used as a non-pharmacological countermeasure for drowsiness across a range of occupational, medical, educational and military settings.

There is enormous potential for developing these basic findings into real-world clinical and occupational applications in order to provide lighting that improves human health, safety and performance. Given the different, and sometime competing, spectral sensitivities of the visual and circadian photoreception systems, optimizing these multiple effects of light may require complex ‘smart’ lighting systems. The challenge to architects and lighting designers is to incorporate these basic findings into lighting that optimizes both the visual and non-visual effects of light simultaneously and safely.

Steven W. Lockley, PhD, Assistant Professor of Medicine, Division of Sleep Medicine, Harvard Medical School, Associate Neuroscientist, Division of Sleep Medicine, Brigham and Women’s Hospital.

Prospective Design Implications of Recent Findings in Photobiology
by Marilyne Andersen

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

Recent studies have attempted to link environmental cues, such as lighting, with human performance and health, and initial findings seem to indicate a positive correlation between the two. Insufficient or inappropriate light exposure can disrupt normal circadian rhythms which may result in adverse consequences for human performance, health and safety. This presentation will discuss how the current state of the art in photobiology can prospectively be applied to architectural design, with a focus on healthcare and housing environments.

Outcomes of photobiology research were used in the presented work to define threshold values for illumination in terms of spectrum, intensity, and timing of light at the human eye, and were translated into goals for simulation – and ultimately for building design. In particular, the climatebased Daylight Autonomy (DA) metric was chosen to simulate the probabilistic and temporal potential of daylight for human health needs.

While no actual recommendations can – or should – yet be made because of our limited understanding of the effects of exposure to light on human health and circadian organization, especially during daytime, we can still discuss the relevance of some critical design parameters to electric lighting or – to a greater extent – daylighting. Typically, factors most influential on the perceived light spectrum, intensity and duration should be analyzed such as luminaire type, glazing fraction, interior surface reflectances, façade orientation, space use and dominant view directions.

The field of circadian daylighting in architecture is a new one. Because photometric quantities such as lumens are keyed to visible light rather than circadian sensing-shifted light, they are not useful to determine if a space has sufficient light of the correct spectrum for circadian realignment without considerable calculations. The work that will be discussed should lead to a better understanding of the relative effect of design decisions such as window size, position and materials; two particularly representative case studies were chosen to test the developed methods, namely hospital rooms and Boston rowhouses. This pioneering work opens up the discussion to design and renovation suggestions, keeping in mind that given the very early development stage of photobiology in this field, any finding has to be considered as a possible approach to solve the problem rather than as absolute design guidelines.

Marilyne Andersen is a physics engineer whose principal research interests are the use and optimization of daylight in buildings, which led her to inter-disciplinary exchanges between architecture, physics and environmental concerns. At MIT (Massachusetts Institute of Technology), she leads the Daylighting Lab since 2004.

Her current research focuses on advanced glazing and shading systems, on daylight redirecting devices, on visual and thermal comfort and the design implications of light on health, as well as on the visualization of daylighting performance and metrics in design.

Here Comes the Sun
by Tor Nørretranders

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

Why is it that daylight makes us so happy? And why it is that bright sunlight makes us even more joyful? What is so wonderful about a blue sky? Neurobiology is not enough. We need planet science and cosmology to understand all of this.

Tor Nørretranders is an independent author, thinker and commentator based in Copenhagen, Denmark, serving an international audience. Generally seen as a leading science communicator of Denmark, Tor Nørretranders has involved himself in numerous activities in the public arena, from newspaper journalism through books and magazine articles to hosting and producing television shows on science and the general world view. His lecture tours, gathering tens of thousands of people, have been major events on the Scandinavian scene.

Originally graduated as a M.Sc. in environmental planning and the sociology of science, Tor Nørretranders has been academically employed at the Technical University of Denmark, The Royal Academy of Fine Arts and the Risø National Laboratory. He is now adjunct professor in the philosophy of science at Copenhagen Business School. His scientific publications include studies of pattern formation in fluids, the information content of conscious experience and the output and quality of Danish science.He has been involved in creating collaborative networks of artists and scientists. Tor Nørretranders has published 20 books spanning issues from the worldview of science and the role of science in society to environmental issues and the realm of human experience and consciousness:

“The user Illusion” from 1991 became an international bestseller, even though it is a 500-page treatise on the role of consciousness in human affairs, based on material from physics, mathematics, psychology, neurophysiology and the history of ideas.

“The Generous Man” from 2002 deals with the role of generosity and sociality in human affairs. The book provides support for the notion that humans are not at all like Homo economicus, the selfish and rational actor in most economical theory. Humans do in fact want to cooperate and to be generous.

Other more recent titles deal with issues spanning from the role of faith outside the world of religion, the scientific debates over human nutrition and obesity, as well as a biography of Albert Einstein. In 2007, his book ”Civilisation 2.0” launched an optimistic view of the coming epoch of a sustainable hi-tech society. A book on the role of joy in human lifte created a huge interest as did a book for children on how the world works. In 2008 “Green light” followed up on the environemtal issues. A second volume with questions and answers for kids was also published.

Tor Nørretranders has received the non-fiction prize of the Danish Writers Union in 1985 and the publicist prize of the Danish Publicist Club, 1988. His books have been published in Norway, Sweden, Finland, Estonia, Holland, Germany, Romania, England, USA, Japan and Korea.

Daylighting Legislation and Health
by Mohamed Boubekri

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

Over the last three or four decades, discussion about daylighting as a viable architectural design option has been linked to the debate about energy conservation in architecture. Daylight in general, and sunlight in particular, are vital to life on earth, and it is not difficult to believe that their absence fosters conditions that promote disease. Through photosynthesis and other processes, sunlight provides photochemical ingredients necessary for our lives. There are fundamental biological, hormonal, and physiological functions coordinated by cycles that are crucial to human life. A 1998 World Health Organization report (1998) noted that up to 30% of new and remodeled buildings worldwide may be linked to health problems. The effects of poorly designed buildings, whether in terms of limited access to sunlight or poor indoor air quality, continue to affect the health of building occupants. Tall buildings eclipse streets, limiting the movement of fresh air, eroding the immediate connection between ourselves and the natural environment. There are serious health effects due to lack of exposure to sunlight. Lack of sunlight exposure causes serious vitamin D deficiencies, which in turn cause of range of health issues such as osteomalacia and bone frailty, internal cancers, seasonal and normal depression among others.

As people spend increasingly more time indoors due to work reasons, the issue of the lack of daylight and its impact on the health of building occupants becomes ever more salient. Yet building codes and lighting standards are still inadequate in dealing with the issue of daylighting. Increased urbanization since the turn of the 20th century has led to the erection of concrete, glass, and steel skyscrapers. A review of daylighting standards worldwide shows that the so called daylighting standards prescribe either a certain window or at the very best a daylight factor. Daylight factor prescriptions tend to be mere recommendations. No obligatory requirements for daylighting in fact exist. Most countries require windows for building. Legislation based on window size may be only incidental to daylighting as generally no requirements for window controls, shading, etc. In order for daylighting legislation to be effective, prescriptions based not only on daylight factors should be required, but also duration of daylight penetration.

Mohamed Boubekri, PhD, Associate Professor, Practice and Technology Faculty, School of Architecture, University of Illinois at Urbana-Champaign.

The role of daylight in the existent and future French building regulations
by Christophe Martinsons

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

The French building energy code, known as “RT”, French for thermal regulation, aims to promote energy efficiency by requiring an assessment of building energy performance. Since 2000, electric lighting has been formally included in the calculation of the overall building energy consumption, thereby giving an incentive to use efficient lighting equipment and maximize daylight availability in rooms.

RT 2005, the building energy code currently in use, is based on an hourly energy calculation method that uses climatic data input. This lecture will first present the specific method of daylight calculation in buildings. The relationships between daylight and artificial lighting consumption will be detailed. These successive steps are associated with many underlying approximations that will be emphasized in the presentation because they clearly limit the accuracy and applicability of the method.

Compliance to RT 2005 is defined by a set of objectives to be met, each one of them relying on the comparison with a hypothetical “reference” building. This reference building has the same architecture, but is assigned with mandatory materials and equipment characteristics (reference values). In other words, RT 2005 only gives a relative assessment of the building energy efficiency. Despite many improvements, this approach has been criticized for its inability to fully reflect the positive aspects of architectural innovations and progress in the building envelope itself.

The next energy code, RT 2012, is being devised by the governmental building directorate with academic partners, such as the CSTB, and industrial stakeholders. Unlike the current regulation, it is intended to provide an absolute method of energy consumption. Compliance will be based on an overall performance level expressed in kWhPE/m²/year. The target fixed by the government is 50kWhPE/m²/year, which reflects an ambitious commitment to reducing CO2 emissions and saving energy. The future regulation should be applicable as early as 2011 for new tertiary buildings. In 2013, new residential buildings should comply with RT 2012.

This drastic reduction of energy use in future buildings poses serious challenges to artificial lighting. For instance, office buildings equipped with the best available lighting technologies show that lighting consumption exceeds half the 2012 threshold. Today, the most significant ways to reduce lighting consumption are (1) to promote the optimal uses of daylight devices and solar protections, (2) to use daylight-responsive artificial lighting systems with gradation and zoning capabilities and (3) to implement control strategies based on the actual presence of people.

This lecture will show how the RT 2012 lighting calculation method can fix some drawbacks of the current method, while providing a better characterization of daylighting devices and sensor-based control systems.

Christophe Martinsons, Centre Scientifique et Technique du Bâtiment (CSTB). Head of Lighting, Electricity and Electromagnetism division.

Daylight and Comfort in the indoor environment
by Myriam Aries and Laurens Zonneveldt

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

Daylight is not only the natural source for lighting, it is also proposed as one of the sources to save energy and reduce energy consumption. However, in order to save energy, comfort and health conservation are required prerequisites. To asses comfort in the indoor environment, most authors only differentiate between comfort and discomfort. A more refined scale for assessing the level of comfort is proposed. The use of this scale is illustrated with a number of examples, in this context based on daylight conditions. Simultaneously, several interactions of the complex interactions of these daylighting parameters with other comfort aspects are demonstrated.

Myriam Aries is currently working with the Energy, Comfort, and Indoor Environment group of TNO Built Environment and Geosciences. After a Building Technology master project related to daylight and visual comfort at the TU Delft, she conducted a Ph.D. research project at the TU Eindhoven with regard to human visual and nonvisual lighting demands and the realization of healthy lighting. She expanded her knowledge while working as post doctoral fellow within the lighting group of the NRC Canada.

Laurens Zonneveldt is currently working with the Energy, Comfort, and Indoor Environment group of TNO Built Environment and Geosciences. He studied Physics and Meteorology in Utrecht and has been working for over 25 years in lighting research with the focus on daylighting. Over the years, he has participated in numerous international projects on energy efficient lighting and visual comfort.

Daylight and Modernity: design and redesign of the Van Nelle Design Factory
by Wessel de Jonge

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

In the modern movement daylight is a symbol for health, hygiene, leisure time and hope for a new transparent society. How are these qualities captured in the redevelopment of the Van Nelle Design Factory in Rotterdam (Brinkman & Van der Vlugt, 1925-30), Sanatorium Zonnestraal in Hilversum (Duiker, Bijvoet, 1928-31) and the Dutch pavilion at the Biennale in Venice, Italy (Rietveld, 1953-54).

The Van Nelle Ontwerpfabriek is considered an iconic building of Dutch Modernism. The building, completed in 1931, was used for the industrial processing of tea, coffee and tobacco. After its renovation and reopening in 2004, it now houses modern offices and business. The building is listed by the UNESCO as World Heritage Site.

Zonnestraal Sanatorium was completed in 1932. The building was designed to house tuberculosis patients. Work on recovery of the decaying buildings was completed in the summer of 2003. The main building is today used as a conference centre, and the other buildings as a rehabilitation centre.

During the Modern Movement, the transparency of buildings was a sort of cultural paradigm, a general idea which reflected a society that – so the architects thought – was equally transparent in its organization. This idea is reflected in the extensive use of glass in buildings. At Van Nelle, for example, the scheme of the building is totally defined by the use of daylight. The depth of the building was limited to 19 metres, a measure that was based on a simple calculation: Daylight would enter the workspaces from both sides, and even in the middle of the floor, workers should be able to perform their tasks under daylight conditions. So these very rational requirements and calculations led to an extraordinarily long and shallow factory building.

In Zonnestraal, things are more or less similar. The buildings are also very shallow, mostly not more than 7,5 metres.  Zonnestraal was also unique in the respect that the patients were accommodated in small rooms. The normal practice in those days was to have 10 to 12 people together in a larger room. At Zonnestraal, in contrast, the rooms were only three metres deep, which meant that daylight could get in very well and cover the entire floor area, effectively killing the germs in the room.

Wessel de Jonge (1957) graduated in architecture at Delft University of Technology, The Netherlands, in 1985. He has been the co-founder of DOCO MOMO International and served as the Organization’s International Secretary and the editor of the DOCO MOMO International Journal from 1990–2002. As a practicing architect, Wessel de Jonge has restored buildings by several ‘masters’ of the Dutch Modern Movement; he has been in charge of the restoration of Gerrit Rietveld’s 1953 Biannual Pavilion in Venice (Italy), the restoration (in co-operation with Henket Architects) of the former Zonnestraal Sanatorium in Hilversum designed by Jan Duiker and of the large-scale rehabilitation project (in collaboration with Hubert- Jan Henkel) for the Van Nelle Design Factory in Rotterdam, designed by Brinkman & Van der Vlugt.

Climate-Based Daylight Analysis for Residential Buildings
by John Mardaljevic

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

This presentation describes a parametric study of daylight provision for two residential building types with and without various skylight configurations. Each of the ten building configurations was evaluated for all combinations of eight orientations and six climate zones. Thus daylight provision was determined for 480 unique cases using validated climate-based simulation techniques.

The evaluation of daylight provision was founded on the useful daylight illuminance (UDI) scheme, which determines the occurrence of absolute levels of illumination within four ranges: less than 100 lux; 100 to 500 lux, 500 to 2,500 lux; and, over 2,500 lux. The limits of these ranges are founded on human factors data from occupant surveys.

The study revealed the enormous variability in internal daylight provision that is revealed when realistic account is made of the naturally occurring sun and sky conditions as derived from standardised climate files. The study demonstrates that it is now possible to tailor the glazing and skylight design of a residential building to the specifics of the building aspect and the prevailing local climate.

John Mardaljevic, BSc, MPhil, PhD, Institute of Energy and Sustainable Development at De Montfort University, The Gateway, Leicester. Has a first degree in physics, and MPhil in astrophysics and a PhD in daylight simulation. His first significant contribution in the field of daylight modelling was the validation of the Radiance Lighting System under real sky conditions. John Mardaljevic has proposed a new climate-based metric called “Useful Daylight Illuminance” as a replacement for the daylight factor.

Designing with daylight under large roofs
by Paul Kalkhoven

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

The design of ever larger deep plan buildings such as airports have used natural light from above to create airy, clear and generous public spaces. Over the past years this has been developed in projects by Foster + Partners with the help of computer technology to achieve all the benefits of natural light, but increasingly to also filter out solar heat gain. Advanced computer modelling enables the design and positioning of rooflight openings and not only to track their impact on the interior spaces, but also to mould those spaces around the light. These techniques are increasingly important in more extreme tropical climates to optimise passive and natural lighting methods, whilst avoiding overheating.

Foster + Partners’ architecture is driven by the pursuit of quality – a belief that our surroundings directly influence the quality of our lives, whether in the work place, at home or the public spaces in between. It is not just buildings, but urban design that affects our well-being. We are concerned with the physical context of a project, sensitive to the culture and climate of their place. We have applied the same priorities to public infrastructure world-wide – in our airports, railway stations, metros, bridges, communication towers, regional plans and city centres. The quest for quality embraces the physical performance of buildings.

Paul Kalkhoven studied architecture and town planning at the University of Technology in Delft in The Netherlands. He joined Foster + Partners in 1985, working with the Terminal building at Stansted Airport. This was followed by a series of projects in Germany, including the Commerzbank Headquarters in Frankfurt, the Agiplan Headquarters extension in Mülheim and the Micro Electronic Centre in 24 25 Duisburg. Subsequently, he worked on the World Port Centre tower in Rotterdam, the competition-winning design for the Gerling.

Tools and Metrics
by John Mardaljevic

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

It is now widely recognised that the half-century old basis of current daylighting guidelines is long overdue for revision, and that new metrics founded on realistic, climate-based measures of daylight are needed. In this Workshop, the audience will be invited to contribute to a discussion on the formulation of new daylight metrics that will meet their requirements as a stakeholder, be they building occupant, architect, engineer, etc.

The four presentations will set the scene for each of the discussion sessions, focussing on issues such as: composition of the metrics (e.g. illuminance and/or luminance quantities), computational practicalities and enduser tools.

John Mardaljevic, BSc, MPhil, PhD, Institute of Energy and Sustainable Development at De Montfort University, The Gateway, Leicester. Has a first degree in physics, and MPhil in astrophysics and a PhD in daylight simulation. His first significant contribution in the field of daylight modelling was the validation of the Radiance Lighting System under real sky conditions.

Daylight, sustainability and health in architectural education
by Rolf Gerstlauer

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

The workshop will a.o. refer to an ongoing teaching experiment/research by design program at The Oslo School of Architecture and Design (Studio B3 and Architecture & Film) working with experimental architectural design and film/video to further investigate the properties of architectural space. The aim is to develop new insights on how architecture as an ‘infrastructure’ can connect to nature and culture again.

Rolf Gerstlauer, 1964 Chur/Switzerland, is Professor at the Oslo School of Architecture and Design. He is besides Per Olaf Fjeld and Lisbeth Funck the third member in the experimental Studio B3 (designstudio for masterstudents in architecture) and teaches also, together with his partner Inger Molne, an elective course on ‘Architecture & Film – morphology of body and space’. He works in his own Studio Gerstlauer Molne (since 1992), besides the production of architecture, extensively with photography and experimental film.

Sustainable building design in relation to daylighting
by Kees Duijvestein

13-05-09 Velux daylight symposium Rotterdam the Netherlands.

Daylight plays a major role in good building design and becomes even more important when the impacts of daylight on energy consumption and the liveability of the inhabitants are considered. Energy consumption, liveability ,health (and thereby daylight) are important parameters in sustainable building design The workshop will be initiated by three presentations on lighting in a sustainable building context, followed by discussions on priorities and ambitions. The discussions will be structured by means of the so called DCBA method.

Kees Duijvestein is awarded for his significant contribution to the development of sustainable buildings in the Netherlands. Apart from his chair as professor in “Sustainable Building” at the TU Delft, Kees Duijvestein is working as a consultant and has participated in and given inspiration to many projects: Ecolonia in Alphen aan den Rijn, DE Wijk in Tilburg, Nieuwland en Vathorst in Amersfoort, Groote Wielen in Den Bosch, Schalkwijk in Haarlem and Stad van de Zon in Heerhugowaard. Kees Duijvestein has developed the DCBA method – a design method that can help the designer to deal – in a structured manner – with the numerous possibilities he has.

Dutch Light – the movie
by Pieter-Rim de Kroon



There’s an ancient myth that the light in Holland is different from anywhere else, but it has never been put to the test. It’s the legendary light we see in paintings. The German artist Joseph Beuys, however, says that it lost its unique radiance in the 1950s, bringing an end to a visual culture that had lasted for centuries.

Dutch Light breaks new ground by examining this renowned but elusive phenomenon. What is Dutch light? Is the light in Holland really different from that in other parts of the world? What is true, what is myth, what is fiction? And was Joseph Beuys right? Dutch Light addresses these fascinating questions. And it is an ode to light and to observation. It turns looking into a new experience.

Pieter-Rim de Kroon, successfully concluded the Dutch Film and Television Academy in Amsterdam (1981) as a film director and lighting cameraman. During the years de Kroon specialised himself in  complicated shooting technics such as High Speed, Motion Control, Time Lapse, Microscopy, Chromakey, Live Action combined with Animation, Wescam, etc. As film director and lighting cameraman he won a great number of national and international awards (over 100) and many Grands Prix.

Visit for more information about the movie.


14 MAY 2009
Constructing the Ephemeral - Light in the Public Realm
by James Carpenter

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

James Carpenter is considered to be a leading architectural designer and innovator in glass and material technologies and he has achieved fame as a light artist and designer of filigree glass constructions. He masters the entire toolbox of light design with a degree of skill attained by only very few of his contemporaries: its refraction and concentration, its absorption and reflection, its colour and its rhythmics. Carpenter designs sensual total art works that constitute far more than simply a decorative add-on to the buildings of others. His interest in architecture and structure has evolved into a unique design practice and studio, James Carpenter Design Associates, a multi-disciplinary architectural design firm with a specific focus on the exploration and management of light. The firm specializes in both the aesthetic and functional development and documentation of enclosure systems, glass structures and skylights, and specialty construction on building skins.

James Carpenter studied architecture and sculpture at the Rhode Island School of Design, graduating in 1972. He actively exhibited his sculpture and installation film projects throughout the US and Europe, and from 1972 to 1982 worked as a consultant with Corning Glass Works in Corning, NY, researching the development of new glass materials including photo responsive glass and various glass ceramics. These projects were aimed at potential architectural applications, utilizing the technical capabilities of such glass to control and manipulate light and information.

James Carpenter is the recipient of numerous awards including the National Environmental Design Award from the Smithsonian Institution and the AIA’s Honor Award. In 2004, he received a prestigious MacArthur Foundation Fellowship. He is founder and principal of the firm James Carpenter Design Associates in New York. In addition to this he is also a principal of the firm Carpenter/Norris Consulting, Inc., with partner Davidson Norris. In 2002, James Carpenter and Luke Lowings opened a studio, Carpenter/Lowings Architecture and Design Ltd., located in London.

Solar Heat vs. Solar Light
by Javier del Rio

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

Heat and light have been always the great challenge to control in architecture, in ancient times this was achieved with simple solutions; no mistakes were done and based only in the experience and common sense. Nowadays this is designed separately from the building, by means of artificial equipments that regulate the thermal and visual comfort, involving heavy energy wastes. In the near future this must change again: a mixture of the past with the present.

In developed and undeveloped countries this is of great importance; in the first because they complicate the world environment and in the others, to reach progress without complicating their own existence.

Javier del Rio, Energy Consultant, Architect PUC, AA Dipl (Hons) Energy Programme, UK, Sustainable Architecture Master Programme Coordinator, School of Architecture, UNAB, Santiago, Chile, Honorary President of the Chilean Association of Solar Energy.

TimeLight - a theoretical investigation
by Federico Favero

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

Time-Light is a theoretical investigation on the relations between the person and the environment in the temporal and spatial dimension. It analyses a series of questions: What is our relation to time? How does light make time visible? And finally: How do these conditions impact Lighting Design and our well-being?

Time is a substrate and basic condition of all life. Light is the most important source of life on the planet and is the energy that makes the heart of the world tick at its daily, seasonal and yearly rhythm. In the natural world one is the element that provides all the information about time: day and night, represented by the cycle of light and darkness. Light variations are thus the basic agents of transformation of the environment and we have been exposed to these conditions for millions of years. Researchers in the lighting field have only recently placed man in the spatial and temporal context.

The point of view of this paper is that proper lighting conditions in the future must be conceived in space and in time. The entrainment to the natural cycle of darkness and light, of night and day, is essential for the wellbeing of the person. It is possible that most of the issues related to light exposure, starting from S.A.D., are a consequence of a de-synchrony between the person and the environment. This de-synchrony could be connected to the “conditions of exposure” in the space. The person experiences reality through frames that are both physical (space and time) and cultural, and these frames change the way we experience reality. Thus the environment and the modality of interaction have a major relevance in the perception of events and in the creation of the personal self. A vast series of cultural and biological differences can be explained by exposure to different conditions of the environment. Future investigation on these frames (conditions of exposure) is necessary in order to create better work and living spaces.

The research outlines the relations between man and his environment (Background) and the basic feature of time in our physical world (SunTime). Circadian rhythms and the study of body and mind synchronisation (Entrainment), are based on research in chronobiology and neurobiology. Three cases exemplify different attitudes toward the design of Architecture connected to temporality.

Federico Favero, KTH-STH Kungliga Tekniska Hogskolan – School of Technology and Health, The Lighting Laboratory, Sweden.

Energy efficient daylight solutions, trends and chances
by Wilfried Pohl

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

Daylighting has become a frequently used phrase in architecture, but in reality not so much has changed in the last decades! The use of daylight means to design façade and window solutions, which are able to meet the contradictionary requirements like

  • guiding daylight into the depth of the building
  • shading the solar heat in summer, using it in winter
  • protect the occupants against glare
  • allow a good view to the outside

Additionally, these functions have to be fulfilled while the outdoor conditions (day- and yeartime, weather) and the indoor demands are changing continuously. Despite this complex context the ‘glass and steel architecture’ with fully glazed facades was booming the last years. The author will present an overview of the energy saving potentials of daylight techniques and will show future trends and chances.

Wilfried Pohl studied mathematics and physics, since 1985 employed by Bartenbach LichtLabor. Member of Managing Board, General Manager for Research and development. Leader of various international planning and R&D-projects, dealing with daylighting, artificial lighting, visual perception, light&health, and building physics. Numerous scientific publications, lecturer at different universities and at the university of Innsbruck, Lighting Academy.

Long term assessment of costs associated with lighting and daylighting techniques
by Marc Fontoynont

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

Building lighting and daylighting systems disserve to be assessed over long periods of time (over 30 years) for optimization. The interest is to provide professionals and investors a way to compare the real cost of lighting solutions. This assessments must include product costs, installation costs, maintenance cost, and energy requirements. In our process, the lighting techniques are compared on the basis of illumination delivered on work plane (0.8 m from the floor) per year (Unit: Megalumen.hours/year). The currency is the Euro since all data were computed for the European environment. Performance of daylighting techniques were assessed using climatic data recorded in Lyon, France (Latitude 45.7°N). The selected daylighting techniques were: roof monitors, façade windows, borrowed light windows, light wells, daylight guidance systems, as well as off-grid lighting based on LEDs powered by photovoltaics. These solutions were compared with electric lighting installations consisting of various sources: fluorescent, tungsten and LED.

After classifying the total annual running costs associated to illumination delivered for each system, we found that standard daylighting techniques provide light in a cheaper way than electric lighting (3 to 20 times typically) with best performances reached by rooftops. However, if the objective is to bring daylight deep into building interiors, daylighting solutions appear expensive, except if daylighting guidance systems are employed (using highly reflective coating). Hence the necessity to approach optimal design of daylighting with care, giving high priority to roof systems and facade systems. Core daylighting techniques aiming at bringing daylight deeply in building interiors need a very careful financial assessment.

The study points out however, than if LED lighting options could be delivered at a third of today’s price (30 €/ Klm instead of 100 €/Klm today) LED could become a cost effective solution for indoor lighting, competitive to fluorescent lighting.

This study does not address the life cycle analysis and the environmental impact of lighting systems, which could make daylighting solutions even more appealing.

Marc Fontoynont, Professor, Director Laboratoire Sciences de l’Habitat, Département Génie Civil et Bâtiment, ENTPE. Vice president of CIE (International Commission on Illumination) and Director of CIE division 3. Vice- President of l’Association Française de l’Eclairage (AFE Paris). Marc Fontoynont is responsible for extensive research in the areas of optics, photometry, light distribution, luminous environment perception and daylight characterization.

The Realized Savings Ratio: measured versus predicted energy savings for daylight harvesting
by Lisa Heschong

14-05-09 Velux daylight symposium Rotterdam the Netherlands.

One of the important benefits of daylighting is a corresponding reduction in building electric lighting energy use. Properly designed and installed automatic photocontrols in a daylit space should provide reliable energy savings. The Heschong Mahone Group undertook two studies to compare achieved savings from photocontrol installations against engineering predictions. The first study looked at a variety of 34 “toplit” spaces, and the second study included 123 “sidelit” spaces, all of which included photocontrols. Monitored savings due to operation of the photocontrols (excluding the effects of other types of automatic controls and manual operation) were compared to estimates for each system using the whole building energy simulation tool eQuest (DOE2.1). For toplit spaces overall, a “Realized Savings Ratio” of 98% was found. For sidelit spaces the ratio was much lower, with one half of the systems found to be not functional, and those that were functional only producing one half of the expected savings. This paper will report on our methodology and findings, including system characteristics associated with greater success or failure, and implications for improving the success of daylighting energy savings.

Lisa Heschong is a principal of Heschong Mahone Group and a licensed architect who has divided her professional practice between energy research, writing and building design. As a researcher, she led the project teams, which analyzed the impacts of daylighting on human performance for the Daylighting and Productivity Studies funded through PG&E and CEC. She also led the team that analyzed baseline lighting characteristics and created a computer model of lighting energy use for the State of California Energy Commission . As a writer, she worked with Lawrence Berkeley Laboratories to synthesize their research into Residential Windows: A Guide to New Technologies and Energy Performance (WW Norton). She also is author of Thermal Delight in Architecture (MIT Press), a co-author of the Advanced Lighting Guidelines, the CHPS Best Practices Manual, and the Skylighting Guidelines, all web-based publications. As a lighting expert, she has developed the successful web-based training program for the Federal Energy Management Program (FEMP) and conducted workshops across the country for DOE.

As an architect, Ms. Heschong has managed projects to design high-rise office buildings, K-12 schools, and residences. She has consulted on numerous school designs through the Bright Schools program of the California Energy Commission, and reviewed school proposals for the Office of Public School Construction. She also taught studio design at the Architecture Department of the University of California at Berkeley.