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.

Notes on Complementarity 3

The Case for Non-Uniformly Lighted Spaces

There was a time when a room uniformly illuminated by electric light was seen as innovative and efficient. The opportunity to work continuously and effectively without the drawbacks of the daily and seasonal cycles of day and night, long and short days, represented the promise of increased productivity at work and even at home. Constant and uniformly distributed electric lighting overcomes the unreliability of daylight, which may leave some areas too dark and, just as easily, other areas too bright. Daylight varies from moment to moment. Direct sun can overheat a space in summer while its absence leaves us shivering in the winter. Daylight is just unreliable.

We thought, for a time, that our engineering sophistication and the availability of inexpensive electricity permitted us to overwhelm the inopportunities of the sun. Think of the gleaming insistence of a fluorescent room with its almost subconscious greenish prejudice. Rooms like this broadcast light from so many sources that strong shadows are cancelled. Without shadow, we lack clues to depth, distance, and orientation. There is evidence for a link between uniform electric lighting and worker inefficiency—exactly the opposite of what was planned. More often now, we see the presence of unvarying light, illumination of a constant intensity and color--particularly light of an un-sunlike color bias--and lacking distinct shadow, as discomfiting. Think of a room you hate: this is that room.

To take advantage of daylight, we have to design each façade of a building a little differently. Daylight from different directions has different characteristics and they correspond to different times of day and the seasons. Each orientation of a building has to perform in a different way to provide the correct measure of control over incoming light. The asymmetry of daylight can never be eliminated, but it can be exploited to enliven spaces, animate facades, and gain energy advantages. Building envelope design should be responsive to the sun and skylight and open to variation and so should interior spaces. Architecture thrives when it is responsive, when it accepts and makes sense of the qualities of daylight, including its variability.

Notes on Complementarity 2

The Overlapping and Simultaneous Qualities of Light

It is typical and entirely logical that multiple characteristics of light appear simultaneously. Imagine light doing only one thing at a time. We’d see light sources, but no surfaces would be brightened. Or, we’d have bright wall surfaces without a source. Light in a space might only be one color. We’d have spaces of endless shadow or in uniform dimness. These singular events sometimes happen and they can be dramatic, but it is more common that we see light performing in various ways and altogether sensible that we design spaces that invite an array of daylighted events to occur.

Dependency on one characteristic makes most spaces less useful, less interesting, visually stagnant, and even inefficient. They separate us from the changes in daylight that occur during the day. Change and variation in lighting are not necessarily distracting or confusing. They are necessary.

In most buildings and even within single spaces, we should see a carefully designed range of daylight character and quality. We should see light sources and brightened surfaces, diffused reflected light as well as specular reflections, mirror-like in their accuracy. There should be shadows, shade, dim light, sometimes punctuated with bright sources or a beam of light selecting finding a target, and so on. By these means, among others, daylight may orchestrate the organization buildings. This enables daylight and shadow to direct us, making important things visible, other places stimulating or restful, and whole buildings logical and coherent. Light is not about one characteristic or quality. It is about the ensemble of those characteristics and how they perform together.

Notes on Complementarity 1

All light is light.

Light in the everyday world is delivered by different sources: the sun, fire, electric light fixtures, lightning, and moonlight. Light from those sources may be differentiated in the sense that each source may have more of some characteristics than others. One of those sources is intense, regular, encompassing in its influence, and a requisite for life; one flickers when domesticated, but roaring when it threatens; one is constant, quiet, and subject to fingertip control; yet another arrives in a crooked flash, a near-blinding expenditure of energy; and the last is a cyclical, soft, echo of the first. But what they have in common is equally important. At the level of particle physics, the light from all of the sources is the same thing: radiation within a thin slice of the electromagnetic spectrum. It’s all the same stuff, which means that light from one source works with another without conflict. Light from the sources can be combined and no one source cancels another. The sources and characteristics are often are combined to make rich and varied architectural environments. It also means that there is no such thing as “artificial” light. All light is light.