What's So Great About Daylight (1.0)

At least some part of our fascination with the sun and its light is that it puts us in the unaccustomed position of experiencing action at a distance, the sense that there is some kind of unseen, interactive, relationship between objects remote from each other. We don’t usually think of it this way, but it is astonishing to think that the sun, the unreachable locus of seemingly inexhaustible and fierce energy, would be the cause of shimmering brightness on the wall next to me or that I could then cause the sun’s illumination to bounce across a space onto another surface, unconnected to the first. But this is what happens and what we enable, what we count on to develop practical strategies in lighting and shading the places we design. Casting shadows has some of this quality as well, as bodies of no particular substance are broadcast by one object onto another. Shadows cross legal and physical boundaries with silhouettes that more or less follow the contours of the source or are transformed into odd shapes that stretch, compress, or mock their origin. The distance between the source of light or the origin of a shadow and the surface on which they come to rest implies that there is no connection across space, but the quality of light, the accuracy of a shadow or its telltale adjacency to its source suggest a connection and even complicity.

Everything is illuminated

An acknowledgement or two

“This work began with the hypothesis that the thermal function of a building could be used as an effective element of design….An analogy might be drawn with the use of light quality as a design element, truly a venerable old architectural tradition.”

Lisa Heschong, Thermal Delight in Architecture [1]

This work began with the hypothesis that there is no great architecture that does not include a response to daylight. [2] It is true that there is an ancient tradition of using daylight in the design of significant public architecture. But although daylight, as a critical component of architectural design, is frequently acknowledged, it is infrequently discussed seriously and then often with florid poetics that skip lightly over specifics [3] and therefore miss the poetry, too. [4] More recently, light has been mathematicized, analyzed with incredible precision and made subject to discernment by expensive instrumentation, but its significance, to most designers, is further obscured. Daylight is rarely discussed in such a way that architects can use the information in practice, [5] and not in a way that recognizes the vast influence that it might exert on design beyond dazzling effects and the everyday necessities of navigation.

And not only is it nearly a requirement of great works to address the availability of daylight, vernacular building traditions have always addressed it. Until recently, it was impossible to do otherwise. The only alternatives to daylight required that we set things on fire to gain illumination of varying quality and dependability. So, it is worth asking why are there not serious and accessible discussions about daylight, why contemporary architects (including a long and growing list of notables) ignore it and generate form for its own sake, and how we might address our lost vernacular knowledge of light, heat, and cold. We have misplaced our practical knowledge of configuring and locating openings. Instead, we dare to emulate greatness, but mostly for formal characteristics and provocative imagery rather than to design buildings that reveal to us how they actually perform in the light of day. Heating, cooling, and lighting [6] are still, 30 years after Ms. Heschong offered her hypothesis and evocative observations, events that manifest themselves, typically, with the flip of a switch. They are treated as if they were non-architectural subjects and most of our architecture—and our buildings—makes this clear.

Only a small portion of the electromagnetic spectrum is perceived as visible light [7] but it is the energy in this slim range of the spectrum that stimulates our eyes and provokes our minds so that we can “see.” Remarkable then that it is within this small range that we understand our world best. It has been estimated that humans receive 80% of their information about the world through our eyes. [8] Most of us understand our circumstances best, most reliably, and safely, by using our eyes and it therefore seems to us that we are steeped in daylight, which is only a tiny proportion of the radiation that engulfs us. So, it seems that everything is illuminated--everything of value, that is; we place a lot of value on what we can see. We organize our lives in reference to light; our sense of time and location is measured with the light of the sun and its position or absence in the sky. The logic of the sun, its rhythm and power, have been transferred to other technologies: the clock, the compass, the programmable thermostat, fossil fuel engines, and electric light fixtures; allowing us to convince ourselves that we have control over all of this and that daylight is a standby solution, a “Plan B.”

Our vision tells us that we are enveloped in illumination and it may be this commonness of daylight that enables us to pass it off as unworthy of mention, emphasis, cultivation, or celebration. Why bother with something you’ve got lots of unless its appearance startles you, as with a great sunset or a bolt of lightning, a sunny winter day, or when it bleaches you with an onrush of brightness projected squarely into your eyes? People living in regions of the world where solar radiation is either sparse or superabundant have always had to tie their living conditions to the availability of light and heat and these patterns sometimes persist in their architecture and cities, establishing cultural expectations that are continued by the best architects. See Alva Aalto’s work in Finland, Peter Zumthor’s in Switzerland, Raphael Moneo’s in Spain, and projects by others. These architects have incorporated in their work, a respect for intrinsic local traditions, for making spaces by gathering, diverting, and reorganizing the sun’s heat and light. As a result, spaces in these cultures are designed as articulate built responses to a particular place in the world with its special rhythm of the sun, regional climate and local weather, and its landscape.

It should be clear to us, by now, that the supply of energy to be found in the ground is neither inexhaustible nor free for the taking. Evidence to the contrary grows larger everyday and it is possible to envision an architectural scenario where aspirations to greatness and the practical needs of everyday building coincide in the regular use of daylight for all of the many good reasons. In order to do this, we need to make such strategies available and comprehensible. The use of daylight should be as accessible to architects as common construction and planning principles, those rules of thumb, as we call them, that professionals use every day, thoughtfully, but without wringing their hands over them as if it was all new. For example, the location of a window in a wall with the aim of providing the most useful daylight, at the appropriate time of day, should be decided with the same sureness that we use to position 2 x 4’s at 16 inches on center. Effective, and meaningful daylighting strategies should be as evident in our buildings as are simple construction techniques, and at least as legible in the outcomes. All of the great daylighting ideas area based in common sense, everyday experiences of sunlight, as it streams toward us and is either absorbed, transmitted, or reflected because that’s just about all that light does.

This work begins with the notion that an architect’s knowledge of daylight is capable of stimulating a convergence of good sense and great outcomes. It begins with the hypothesis that Lisa Heschong was right.

Notes

[1] Lisa Heschong, Thermal Delight in Architecture, MIT Press, 1979, page vii

[2] If the reader can find an exception to this, I’d like to know what it might be. If you are thinking, “pyramids,” please

see example, “The Eye of Ra, by K. Levin, in Light in Art, edited by Thomas B. Hess and John Ashbery, New York:

Collier for Books, 1971.

[3] Henry Plummer, Poetics Of Light, Tokyo: A+U, 1987

[4] John Ciardi, How Does a Poem Mean? 1959

[5] In spite of all of the math-based lighting books, few architects need to calculate the number of footcandles incident on a

surface, but all should understand the appropriate use of sunlight. On the other hand, even Louis I. Kahn’s discussions of

daylight can be slippery.

[6] And acoustics, too.

[7] Gotta find my source for this.

[8] Ibid.

See my new book!

Daylight and Meaning in the Architecture of Gunnar Birkerts

You can read the text of my article on Gunnar Birkerts (and earn AIA continuing education credit) at this address: http://www.louispoulsen.com/en-us/Downloads/Literature/AIA_CES%20Credit.aspx

L’Institut du Monde Arabe

[Mechanical devices]

For L’Institut du Monde Arabe (The Arab World Institute, 1981-1987) in Paris, Jean Nouvel devised a system of mechanical diaphragms that open and close in response to daylight. The installation is formidable and sleek, with the diaphragms, which vary in size and configuration, located within the void of a double glazed assembly. Each such module, with its array of 121 operable diaphragms, is approximately 9’ – 6” (290 cm) square.1 The modules take up all but the ground floor level of the eleven-story structure at the south elevation, so that the daylight-receiving façade, in effect an automated shutter system, is ten modules high by twenty-four modules long. It’s big.

The individual diaphragms are much like those found in a traditional camera. The aperture size changes by means of a ring by overlapping stainless steel elements that open or close to permit more or less light to pass through. Computerized light sensors signal a system that activates these shutters. Changing south light is signaled by rapid clicking sounds, the movement of the diaphragm blades, galloping across the façade. The sight and sound of the adjusting diaphragms is reminiscent of the information updates on an old train station itinerary display.

Each intricate diaphragm is composed of reiterative geometric shapes. This design motif is familiar to us from the world of photography but also reminiscent of traditional Islamic geometric artworks. It precedents can be found in graphic designs such as garden plans,2 rugs, tiles, and traditional light-filtering screen work and plaster relief in Islamic Spain where they filtered sun and developed shadow. The geometries were always employed to delight the eye, organize surfaces, and regulate light. In a departure from traditional Islamic installations, at the Institute, control devices, switches, tubes and signals, are fully exposed as well. The geometries tie the program of the building to its cultural roots, founded in a part of the world characterized by intense sun and heat.

The smooth packaging of the devices behind tinted glass means that the they are not available to catch sunlight and make patterns of shade and shadow as they would, say, at the Alhambra. In Granada, the sun is higher in the sky and it grazes the plaster reliefs to create shadows. In Paris, where the sun is lower and the sky more frequently overcast, the diaphragms regulate sunshine and diffused skylight that is more perpendicular to the façade.

One would like to say that Nouvel’s installation is innovative in the sense that it suggests a method of regulating daylight that others might employ, but this is not entirely so. The dependence on so many moving parts--a mechanical system--is as close to the thinking of our time as it is to the time of the Eiffel Tower (1889) with its graceful celebration of custom-fabricated structural and spatial elements. Nouvel’s marvelous array of shutters is not so different from the Tower’s exposed members, except that his move; or from the many, nearly useless gears and levers in Charlie Chaplin’s film, Modern Times (1936).3 (What do they really accomplish?) But we’ve moved beyond the age of moving parts to a world of pixels, and smaller elements: we are now able to regulate light at the molecular level. At the larger scale of architectural works, an understanding of daylight suggests that there is a greater advantage to permitting the sun to move across elements correctly located in the path of its radiation. Moving parts don’t necessarily offer a useful increase in our ability to control sunlight, at least not one that is warranted economically. It is usually better to let the sun do the moving.

As we have seen at the Alhambra and elsewhere, traditional wood screens, fixed in place, work just fine, as do traditional shutters with manually operable blades or panels, such as shutters. In fact, Nouvel’s shutter system, with its many moving parts, does not always operate properly. Fortunately, L’Institut du Monde Arabe is quite beautiful, and still effective as a screen, even when stuck: the sun continues to do its work.

1 El Croquis 65 65; Jean Nouvel 1987 1994, Madrid: El Croquis, 1994; page 74

2 Charles W. Moore, William J. Mitchell, and William Turnbull, Jr., The Poetics of Gardens, Cambridge: MIT Press, 1988

3 Charlie Chaplin, Modern Times, (1936) Warner Home Video, 2003.

[stopping time]

Gunnar Asplund’s desire for clarity in the glazing at the Stockholm Public Library came in the wake of his experience designing the small, Woodland Chapel, completed in 1920 at the Woodland Cemetery (Skogskyrkogarden) in Stockholm. Although both buildings are descendents of classical, domed structures, the two Asplund projects are differentiated by their programs and in the way they remake daylight to support those programs.

The Chapel is a pristine, white dome under a steeply hipped, black, shingled roof; with its small size, and roof pulled down close over its walls, it defers, like a hut, to the surrounding trees, which rise from the forest floor to more than twice the Chapel’s height. A note of formality, and what begins to differentiate the building from a cabin in the woods, is struck by the set of twelve, white, polished porch columns.

Inside, tucked under the roof is the unexpected domed ceiling, a half-sphere inscribed in a pyramid. The dome is set over a slightly larger square room, its brightness in counterpoint to the dark roof that shelters it. At every stage in the illumination of the chapel, the sun is deprived of direction to make light that does not change and color that is muted by a sequence of techniques. Not only is the sky often overcast in this climate, but tall pine trees filter much of the direct sun that would come at the chapel from the side of the sky. At the top of the dome, a small, translucent oculus further diffuses light as it enters the room. Once inside, the light is distributed evenly by the dome’s smooth, white, spherical surface, a geometry without corners that would create shadow. Instead, the dome reflects incoming light into the room at an infinite number of angles; the form is a very effective diffuser of illumination.

The square room beneath the dome is painted gray and is larger than the dome, which, as a result, appears to hover in the space. Asplund’s chapel, singular in its vertically axial orientation, is centralized, focused, cool, and light is stilled. Time stops and the cemetery chapel sets itself apart from the world of the living.

The Pantheon

The Pantheon in Rome is a great theater for the display of sunlight. It depends for its illumination on a single opening, an oculus located at the center top of its dome, just where one would expect solidity. The domed rotunda is a great space and vessel for light, but daylight is not distributed as well as it might be.

The entry of sunlight is dramatic. The movement of the sun though the sky can be traced as a bright splash that moves across the interior surface of the dome; the impact of this is heightened by the otherwise relatively low light levels. It’s just not that bright inside the rotunda; inside, it feels a little like inhabiting an old sepia photograph. Top lighting can be very efficient as it is capable of distributing light equally from a central point. In this building, the surfaces of the dome redirect some light downward, but these surfaces are not, or no longer highly reflective. Clearly, the ancient marble floor is reflecting a substantial amount of light back onto the rotunda surfaces. But seeing to the walls sometimes requires additional effort, a squint, to focus on the details.

When you step into the Pantheon, you step from the real world into an ideal world, from the everyday world into an idea about the shape of the universe, from the remains of the Roman Empire into the Roman spiritual cosmos. The visual result is one of visual comfort but at seeing through a thin brown veil, or through history, to the drum’s surface of colored marble and shadowed niches, and coffered concrete.